Active Solar Heating - Universitetet i oslofolk.uio.no/ravi/cutn/solar/ActivesolarHeat.pdf · – A...
69
Active Solar Heating P.Ravindran, Elective course on Solar Energy and its Applications August 2012:Solar Active Heating 1
Transcript of Active Solar Heating - Universitetet i oslofolk.uio.no/ravi/cutn/solar/ActivesolarHeat.pdf · – A...
Active Solar Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 1
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 2
Solar Energy
bull Solar Energy- sunlight that is converted into usable energy ndash Passive solar designs use sunlight to heat a building
without using machinery bull For example Sunlight passing through the windows of a house
may be absorbed by thick walls and then radiate thermal energy
ndash In an active solar system sunlight heats flat collection plates through which water flows
bull The heated water may be used directly for the buildings hot water needs or it may be used to heat the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar energy
bull The sun provides energy for Earthrsquos processes bull Each square meter of Earth receives about 1 kilowatt of
solar energy (energy from the sun) - 17 times the energy of a light bulb
bull Passive solar energy = buildings are designed to maximize absorption of sunlight in winter bull Keep cool in summer
bull Active solar energy collection = uses technology to focus move or store solar energy
bull Solar energy has been used for hundreds of years
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar heats air and water bull Flat plate solar collectors = dark-colored heat-
absorbing metal plates mounted on rooftops ndash Water air or antifreeze runs through the collectors
transferring heat throughout the building ndash Heated water is stored and used later
bull Most water heated by solar panels is used for swimming pools
bull They can be used in isolated locations ndash For heating cooling water purification
bull It is not restricted to wealthy sunny regions
bull Active solar systems generally employ rooftop panels that collect heat from sunlight and store it in water or some other medium
Solar Energy Options
FIGURE 08a An active solar heating
system copy MediacolorrsquosAlamy Images
5 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 2
Solar Energy
bull Solar Energy- sunlight that is converted into usable energy ndash Passive solar designs use sunlight to heat a building
without using machinery bull For example Sunlight passing through the windows of a house
may be absorbed by thick walls and then radiate thermal energy
ndash In an active solar system sunlight heats flat collection plates through which water flows
bull The heated water may be used directly for the buildings hot water needs or it may be used to heat the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar energy
bull The sun provides energy for Earthrsquos processes bull Each square meter of Earth receives about 1 kilowatt of
solar energy (energy from the sun) - 17 times the energy of a light bulb
bull Passive solar energy = buildings are designed to maximize absorption of sunlight in winter bull Keep cool in summer
bull Active solar energy collection = uses technology to focus move or store solar energy
bull Solar energy has been used for hundreds of years
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar heats air and water bull Flat plate solar collectors = dark-colored heat-
absorbing metal plates mounted on rooftops ndash Water air or antifreeze runs through the collectors
transferring heat throughout the building ndash Heated water is stored and used later
bull Most water heated by solar panels is used for swimming pools
bull They can be used in isolated locations ndash For heating cooling water purification
bull It is not restricted to wealthy sunny regions
bull Active solar systems generally employ rooftop panels that collect heat from sunlight and store it in water or some other medium
Solar Energy Options
FIGURE 08a An active solar heating
system copy MediacolorrsquosAlamy Images
5 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar energy
bull The sun provides energy for Earthrsquos processes bull Each square meter of Earth receives about 1 kilowatt of
solar energy (energy from the sun) - 17 times the energy of a light bulb
bull Passive solar energy = buildings are designed to maximize absorption of sunlight in winter bull Keep cool in summer
bull Active solar energy collection = uses technology to focus move or store solar energy
bull Solar energy has been used for hundreds of years
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar heats air and water bull Flat plate solar collectors = dark-colored heat-
absorbing metal plates mounted on rooftops ndash Water air or antifreeze runs through the collectors
transferring heat throughout the building ndash Heated water is stored and used later
bull Most water heated by solar panels is used for swimming pools
bull They can be used in isolated locations ndash For heating cooling water purification
bull It is not restricted to wealthy sunny regions
bull Active solar systems generally employ rooftop panels that collect heat from sunlight and store it in water or some other medium
Solar Energy Options
FIGURE 08a An active solar heating
system copy MediacolorrsquosAlamy Images
5 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar heats air and water bull Flat plate solar collectors = dark-colored heat-
absorbing metal plates mounted on rooftops ndash Water air or antifreeze runs through the collectors
transferring heat throughout the building ndash Heated water is stored and used later
bull Most water heated by solar panels is used for swimming pools
bull They can be used in isolated locations ndash For heating cooling water purification
bull It is not restricted to wealthy sunny regions
bull Active solar systems generally employ rooftop panels that collect heat from sunlight and store it in water or some other medium
Solar Energy Options
FIGURE 08a An active solar heating
system copy MediacolorrsquosAlamy Images
5 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
bull Active solar systems generally employ rooftop panels that collect heat from sunlight and store it in water or some other medium
Solar Energy Options
FIGURE 08a An active solar heating
system copy MediacolorrsquosAlamy Images
5 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Solar Collectors
bull Provide space heating or hot water ndash Usually flat glass covered plates over a black
background where and absorbing fluid is circulating through tubes
ndash A second type is evacuated tube collector bull Each tube along with absorbing fluid pass through a
larger tube
6 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
7
Schematic Solar Heating System (Collector) bull Insulation at base to
reduce heat loss by conduction
bull Black collector on absorber ndash low loss by reflection ndash High absorption of solar
radiation
bull Water pumped through collector (Active System) ndash Heat transfer by forced
convection
bull Double paned glass ndash Reduced loss by
conduction ndash Blocks loss by radiation
(greenhouse effect)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
How solar energy works
bull Active Solar Energy provides hot water by the heat from sunlight to create energy Solar collectors are placed in areas where sunlight is constant
8 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 9
Active Solar Heating
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
What is the main goal of active solar heating
bull They are environmentally friendly
bull Helps save the earthrsquos energy resources
bull It is the best choice for people who have allergies
bull To use a little energy while saving money
bull You can save between 50- 80 on your current heating bill
bull Going solar is an excellent start for reducing energy as well as to saving the planet
10 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
The two different types of Solar Energy
bull Air Based Effective in large buildings Rubber tubes are placed on the roof Air is pumped through the tubes which is then heated The heat is then taken to the housersquos heating system and released through the air ducts
bull Fluid Based Flat plate solar collectors are placed in sunlight Pipes connected to the plates take in water which is connected to a water heater The water is heated then is then pumped through the house heating the house
11 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
What is its overall potential in ldquomaking a differencerdquo into the world
bull Versatility in almost any climate bull Can reduce dependence on imported fossil fuels
especially from OPEC bull Has little environmental impacts only requires
energy from the sun against a solar panelcell effectively placed on the roof of a house for the best energy collection
bull Can give way to new jobs in the production of different types of solar water heating systems
bull Very long lasting and reduces costs in the long run 12
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
How does it work
bull There is five main components of an active solar water heater They are the collectors storage tanks backup heating system circulation system and control system
bull Most of the solar water heaters require a well-insulated tank This two-tank systems preheats the water before it enters the conventional water heater
bull The collector is constructed with an Al box into an all copper absorber plate then a low-iron tempered glass to cover the plate is added to create a greenhouse affect that can deliver high temperatures
bull There are 3 different types of solar collectors for residential applications ndash Flat-plate collector ndash Integral collector- storage
systems ndash Evacuated-tube solar
collectors bull Then there is two types of
active solar heating systems ndash Direct circulation systems ndash Indirect circulation systems
13 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
The Simple Drainback System
Drainback for freeze protection Water as solar fluid Closed Loop Indirect Pre-configured Domestic hot water Hydronic Heat Simple
14 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Active Solar Hot Water System
What additional features are required in an active Solar system compared to a conventional water heating System (European vs American hot water heating systems)
15 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Spirally Augmented Heat Exchanger
SHEMrsquos spirally augmented copper heat exchanger Potable water passes through this coil which acts as a large on demand heat exchanger
16 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Benefits to using Active Solar Energy
bull Active Solar Energy is most beneficial in cold climates with solar resources especially if replacing more expensive forms of energy such as electricity propane and oil heat
bull Solar heating systems also significantly reduce the amount of air pollutants and greenhouse gases that would otherwise be given off by other forms of energy
17 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
18 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwscotlandgovukResourceImg2647890076236jpg
Flat-plate collector
httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagramgif
19
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
httpwwwflasolarcomactive_dhwhtm
20
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Technological Obstacles
bull The start out cost vary from $4000 to $8000 this depends on the following ndash Size of family to be served ndash Size and brand of solar system ndash Type of roof ndash Building codes ndash Orientation of panels
bull Itrsquos not always sunny bull Cold weather
21 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
What politicaleconomical obstacles might disruptstall mass implementation
bull The current recession itself prevents most purchases of solar water heating systems plus the start-up costs to implement them in a home are high which almost nullifies any tax breaks put toward it Low consumer confidence cripples any thought of purchasing them There is also a lack of subsidies more of those go toward fossil fuels There is little public awareness of solar water heating in homes as well
22 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
What are some of the negative environmental impacts with this technology
bull There are almost no negative environmental impacts from this system all it requires is the sunlight from the sun to hit the solar cells that convert that energy to heat so therersquos hot water However solar water heating itself cannot stand alone It is recommended that there is a back-up conventional heating system in place in case the system malfunctions or breaks down There is also a low net energy yield for it since it is preheated and put into a tankcanister this has a chance to cool off so itrsquos best used in the early afternoonevening
23 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
1 Introduction To Active Heating System
An active solar heating system also traps solar energy and does something to improve the collection storage and distribution of that energy
A turtle sunning itself on a rock is an active solar heating system its blood distributes the energy throughout its body and this also improves the efficiency of the heat transfer into the turtle by moving cool blood near the heated surface of its shell [1]
24
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
a) The solar collectors b) The solar storage system c) Auxiliary source of heat
2 Main Components of Active Heating System
25
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Solar Water Heater vs Standard Water Heater SOLAR WATER HEATER
FREE energy from the Sun STANDARD WATER HEATER
COSTLY gas or electric
Annual operating cost $50 Annual operating cost $500+
Storage Capacity 80-120 gal Storage Capacity 40-50 gal
Life expectancy 15-30 years Life expectancy 8-12 years
Lifetime operating cost $1000 Lifetime operating cost $10000
Does NOT pollute environment Depletes fossil fuels
Increases equity in your home No added value to your home
25 return on your investment No return on utility payments
Protection from future increases At mercy of utilitiesgovernment
Hot water during blackouts No hot water during blackouts
26 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Types of Active Solar Heating
bull Liquid based solar heating bull Air based solar heating
27 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
2aCollectors
Flat plate collectors
28 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
29
Flat Plate Collectors bull This is an example of an ACTIVE solar energy
conversion system ndash Active because energy is used to distribute the heat from
where the conversion occurs to where it is needed (forced convection)
bull Heat energy at surface of sun is transferred to a collecting plate by electromagnetic radiation ndash Surface of collecting plate absorbs the electromagnetic
wave energy and converts it to heat energy ndash Heat energy is conducted through the plate to a fluid in
contact with the plate and increases the heat energy of the fluid
ndash A pump keeps the fluid moving past the plate to a HEAT EXCHANGER where the energy is extracted and stored in another fluid for future use
ndash The original fluid with a lower level of heat energy is then returned to the collector plate to gain more energy
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Evacuated tube collectors
30
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Concentrating collectors
31
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Transpired air collectors
32
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 33
Solar Heating of Water Flat-plate Solar Collector
bull Acts like a greenhouse 1 Light energy goes in 2 Converted into heat
energy (infrared) 3 Heat energy is trapped 4 Heat is transferred to
circulating water
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Solar Water Heaters
34 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Active solar energy collection bull Flat plate solar collectors (solar panels) one
active method for harnessing solar energy
35 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 36
Heating Systems
bull Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
37
Active Solar Heating
bull Flat plate collectors are usually placed on the roof or ground in the sunlight
bull The sunny side has a glass or plastic cover bull The inside space is a black absorbing
material bull Air or water is pumped (hence active)
through the space to collect the heat bull Fans or pumps deliver the heat to the house
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 38
Active Solar Heating
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Solar collector system
)]([ OAiLossRSCSC TTUSFAQ minusminussdotsdot=
)( iopSC TTmcQ minussdot=
)()( OAiTANKheatingSCp TTUAQQddTmc minussdotminusminus=
τ
TANKUA)(
LossU
Solar collector
Water flow
Water tank
Area
Property of solar collector (collector heat removal factor)
Total solar radiation
coefficient which define lost of energy from solar collector surfaces to surrounding
define lost of energy from water tank to surrounding
Used energy
39
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
More details about hot water system
40 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 1 Active heating system on a house completely [2]
In this figure we can see crosssection of active heating system
41
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
Figure 2 Systematics of active heating system [3]
In figure 2 systematic of active heating system is shown
42
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Solar systems usually use a specially designed and sized super insulated tank though it may also be an electric tank They serve as a tank where the water is pre-heated
In figure 4you can see easily the storage tank
43
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
2 b) The Solar Storage System
Figure 4 Heated water is collected in the storage tank [5] 44
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 Types of Active Solar Heating System
a) Liquid based heating systems
b) Air based heating systems
45
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 a) Liquid Based Heating Systems
Figure 6 Liquid based system [6]
In figure 6you can see the liquid based heating system
46
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
3 b) Air Based Heating Systems
Figure 7 Air based system [6]
In this figure you can see air based heating system
47
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4Elements of Active Heating Systems
a) Heating Elements
b) Exchanger Elements
c) Heat Storage Elements
d) Fluid and Air Control Elements
e) Temperature Control Elements
f) Safety Control Elements
48
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 a) Heating Elements
Liquid based heater Air based heater
Auxiliary heater
Figure 8 Heating system elements
In figure 8 heating system elements are shown
49
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 b) Exchanger Elements
Liquid based exchanger
Air based exchanger
Figure 9 Exchanger elements
As you see in the figure 9 exchanger elements are shown
50
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 c) Heat Storage Elements
Figure 10 Water tank [7] Figure 11 Rock bin [6]
In figure 10 and in figure 11 heat storage elements are shown
51
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 d) Fluid and Air Control Elements
Valve Check valve
Water valve
Air fan
Figure 12 Control elements
In this figure fluid and air control elements are shown
52
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 e) Temperature Control Elements
Thermostat Thermoresistor
Figure 13 Temperature control elements
You can see temperature control elements in figure 13
53
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
4 f) Safety Control Elements
Expansion tank Vacuum relief valve
Figure 14 Safety elements
In figure 14 safety control elements are shown
54
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
5Advantages of Active Heating Systems [8]
a Easy to install
b Inexpensive to purchase
c Non exhausted energy source
d Friendly for environment
55
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
56
Geometrical Effects of Solar Energy Plate Collectors
bull Total energy collected per m2 are areas under curves bull Note peak power ~1000Wm2 but average 500Wm2 or less for 8-hour day bull Slanted stationary plate is inclined to point at sun at noon bull Actual angles depend on day of year bull Steering is an expensive option for domestic use
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
57
Solar Energy Collectors The Greenhouse Effect (1)
bull The greenhouse effect depends on two physics principles ndashStefanrsquos Law
ndashWienrsquos Law
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
58
Solar Energy Collectors The Greenhouse Effect (2)
ndash Stefanrsquos Law bull This describes how much power an object emits
at a given temperature when all wavelengths are considered
bull PA = e s T4 e = emissivity between 0 and 10 (shiny at low
end dull black at high end 10 is called a ldquoblack bodyrdquo)
s = Stefanrsquos constant (576 x 10-8 Wm2K4) ndash T is the temperature of the object on the
Kelvin scale bull Note the very strong dependence on temperature
- often determines the steady temperature of objects
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
59
Solar Energy Collectors The Greenhouse Effect (3)
ndash Wienrsquos Law bull This describes the wavelength at which the
peak emission occurs λmax = 2898 T microm
ndash Thus for solar energy from the sun λmax = 28986000 = 048 microm
ndash While for the collector λmax = 2898360 = 81 microm
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
60
Solar Energy Collectors The Greenhouse Effect (4)
bull The effect occurs because the ldquogreenhouserdquo glass is transparent to 048 microm but is opaque to 81 microm Thus little energy can escape by radiation and the heat energy (temperature) increases in the enclosure compared to no enclosure
bull This is the basis for solar energy collectors and has relevance to the earthrsquos temperature increase causing global warming to be discussed later
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
61
Schematic Solar Heating System (System)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
62
Calculation for Active Solar Heating (1)
bull What area of flat plate solar collector oriented to point at the sun at would be needed to maintain the temperature at a comfortable level in an average house on a cold winter day in northern Utah ndash Assume the heat energy needed to be supplied to
the house is 106 Btuday ndash Referring to the average daily solar energy input in
N Utah is 44 kWhm2 ndash The flat plate collector will not be 100 efficient -
assume an efficiency of 07 (70)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
63
Calculation for Active Solar Heating (2) bull Calculation
ndash Solar energy needed accounting for efficiency bull Eff = Heat energy to house Heat energy from sun bull Substituting known values 07 = 106 solar heat energy bull Thus by rearranging solar heat = 106 07 = 14 x 106 Btu
ndash Convert kWhm2 to Btum2 bull Using table in book we find 1 kWh = 3413 Btu bull Thus 44 kWhm2 = 44 x 3413 = 15017 Btum2
ndash Calculate area of solar collector needed to supply the house thermal energy
bull Area = Solar heat energy needed solar heat energym2 bull = 14 x 106 15017 = 932 m2 ~1000 ft2 bull This is could be constructed as a panel 50 x 20 ft (quite
large)
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 64
Hot Air Flat Plate System
Thermal mass provided By rock bin Solar collector uses air not water Hot air moved By fan to rock bin or directly To rooms of house Water preheated in rock bin Good for humid climate Not as efficient as water based solar system Why
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
Optimum Solar Collector Angle
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 65
Why does the Optimum collector Angle vary as a function Of the season
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
How Big Should a Solar Collector Be
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating 66
Q = I epsilon A Where Q is the heat I is the average solar insolation at the site Epsilon is the efficiency of the solar collector A is the surface area of the solar collector
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
References
bull httpwwwhealthgoodscom bull httpwwwgreenbuildercomsourcebook bull httpwwwdnrmogovenergyrenewables bull httpwwweereenergygovsolar
67 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
Biography bull httpwwwservicemagiccomarticleshowSolar-Heating-Environmentally-Friendly9762html bull httpwwwenergysaversgovyour_homewater_heatingindexcfmmytopic=12850 bull httpwwwflasolarcomactive_dhwhtm bull httpwwwamecosolarcomSOLARWATERFAQhtml bull httpwwwehowcomhow-does_4966738_active-solar-heating-system-workhtml bull httplsacoloradoedusummarystreettextssolarhtm bull httpwwwwilliamseduresourcessustainabilitygreen_buildingsimagesclosed_loop_hot_water_diagr
amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
References
1 httpwwwnewtondepanlgovaskascieng99eng99068htm
2 httpwwwsolarororgmainhtm
3 httpwwwmashavcomsolar-energyactivehtm
4 httpwwweereenergygovsolarsh_basicshtmlactive
5 httpwwwecnabcasescitutorials_waterhtm
6 httphomeearthlinknet~jschwytzersolarhtml
7 wwwsolar-fitcom waterhtm
8 Solar Energy Research Daniels Farrington Duffie A John 1961 The University of Wisconsin Press
68
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69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
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amgif
69 PRavindran Elective course on Solar Energy and its Applications August 2012Solar Active Heating
- Active Solar Heating
- Solar Energy
- Slide Number 3
- Active solar heats air and water
- Solar Energy Options
- Solar Collectors
- Schematic Solar Heating System (Collector)
- How solar energy works
- Slide Number 9
- What is the main goal of active solar heating
- The two different types of Solar Energy
- What is its overall potential in ldquomaking a differencerdquo into the world
- How does it work
- The Simple Drainback System
- Active Solar Hot Water System
- Spirally Augmented Heat Exchanger
- Benefits to using Active Solar Energy
- Slide Number 18
- Slide Number 19
- Slide Number 20
- Technological Obstacles
- What politicaleconomical obstacles might disruptstall mass implementation
- What are some of the negative environmental impacts with this technology
- Slide Number 24
- Slide Number 25
- Solar Water Heater vs Standard Water Heater
- Types of Active Solar Heating
- 2aCollectors
- Flat Plate Collectors
- Slide Number 30
- Slide Number 31
- Slide Number 32
- Solar Heating of Water Flat-plate Solar Collector
- Solar Water Heaters
- Active solar energy collection
- Heating Systems
- Active Solar Heating
- Slide Number 38
- Solar collector system
- More details about hot water system
- Slide Number 41
- Slide Number 42
- Slide Number 43
- Slide Number 44
- Slide Number 45
- Slide Number 46
- Slide Number 47
- Slide Number 48
- Slide Number 49
- Slide Number 50
- Slide Number 51
- Slide Number 52
- Slide Number 53
- Slide Number 54
- Slide Number 55
- Geometrical Effects of Solar Energy Plate Collectors
- Solar Energy CollectorsThe Greenhouse Effect (1)
- Solar Energy CollectorsThe Greenhouse Effect (2)
- Solar Energy CollectorsThe Greenhouse Effect (3)
- Solar Energy CollectorsThe Greenhouse Effect (4)
- Schematic Solar Heating System (System)
- Calculation for Active Solar Heating (1)
- Calculation for Active Solar Heating (2)
- Hot Air Flat Plate System
- Optimum Solar Collector Angle
- How Big Should a Solar Collector Be
- References
- Slide Number 68
- Biography
-
