What Are Solar Water Heaters
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Transcript of What Are Solar Water Heaters
INTRODUCTIONIn the last decades, infrasonic waves (sound waves in the range of 0.2 to 10 Hz) have
been studied to better understand the physics of sources generated at or near the
solid Earth-atmosphere boundary (Garces, et al., 1998; Drob and Picone, 2003;
Arrowsmith et al., 2010, Marcillo and Johnson, 2010), as a consequence of
natural processes and man-made events. Among these phenomena, underground
nuclear tests and mining explosions can be considered as man-made sources,
whereas oceanic waves, volcanic explosions, earthquakes, and meteors are
examples of natural sources that generate infrasound (Arrowsmith et al., 2010).
Another type of a natural source of inf rasound is related to geyser activity. When
a geyser erupts, it generates pressure waves in the near-infrasound band (1 – 20 Hz)
as high-velocity emissions of water and steam find their way out from the vent.
Geysers may be regarded as analogues for volcanoes due to their similar ities in
seismicity, mass recharge to the system, and eruption dynamics (Kieffer, 1984).
These phenomena facilitate detailed studies on recharge and eruptive processes
(e.g. Kieffer, 1984; Kedar et al., 1996; Kedar and Kanamori, 1998), some of which
would be difficult to perform on most volcanoes (Hutchinson, et al., 1997).The sound
generated by the different types of geyser eruptions may also have analogies
with the sound generated by eruptions observed at volcanoes (e.g. Vergniolle and
Brandeis, 1996; Johnson and Lees, 2000; Rowe et al., 2000; Johnson et al.,
2004; Garces et al., 2003; Ripepe et al., 2007). Even though the amplitudes of the
sound waves from geysers encompass a f ew tenths of Pa to a few Pa when reduced to
1 m, much of the energy released by these geologic features is related to
multiphase fluid dynamic processes similar to those present at some volcanoes.
Towards the goal of better understanding geyser dynamics using infrasound, I
investigated and compar ed the characteristics of three different types of er uptive
behavior recorded from fountain-type (Great Fountain and Sawmill), and cone-
type ( Lone Star) geysers. Three infrasound arrays wer e deployed on these geysers
located at Yellowstone National Park, Wyoming, USA. The spectral content,
acoustic energy, and waveform characterization from each eruptive episode were
analyzed and compared against each other, and against video recordings of the
eruptions when possible. Based on my results, I propose a source model explanation
for the activity observed at Sawmill and Lone Star geysers. Volume estimations from
pulses generated by ejected material during the final stage from the August 11, 2011,
Great Fountain eruption, are also addressed in this work.
2.BACKGROUND
Geysers ar e rare geologic features. Over one-half of the world’s geysers(about
500 active geysers) are located within the boundaries of Yellowstone
NationalPark, Wyoming, turning it into the largest geyser field on earth (Bryan,
2008). Here, the geysers are commonly found scattered among hot springs in ten
major areas known as geyser basins. Geysers consist of a special plumbing system
where hydrothermal explosions occur continuously or intermittently as surface water
enters in contact with hot rocks. The temper ature of the pressurized water rises
until it reaches the boiling point. Then, a mixture of uperheated water and
expanding steam is suddenly ejected into the air. No two geysers ar e alike.
However, they can be classified into cone-type geysers or fountain-type geysers
according to their eruption style, which depends to a great extent on the volume
of water, the size of the constrictions, and geometry of the plumbing system
(Bryan, 2008). The cone-type geysers erupt as a steady, sometimes tall, column
of a mixture of jetted water and steam (Rinehart, 1970). The vent is often
surrounded by mounds or cones of sinter, hence the name. In contrast, the fountain-
type geysers erupt continuous bursts of water from open pools as steam bubbles rise
through them and up to the surf ace (Rinehart, 1970), creating a splashing that
diff ers considerably from the jetting observed at the cone-type geysers. In the
following subsections, the activity and general characteristics of Sawmill, Great
Fountain and Lone Star geysers will be addressed.
2.1 Sawmill Geyser
Sawmill Geyser, located in the Upper Geyser Basin (Figure 1a), is part of one of the
most active groups of geysers in Yellowstone: the Sawmill Geyser Complex. Sawmill
is a fountain-type geyser that er upts bursts of water continuously out of its 1.6 m-
nozzle.Each eruption often lasts f rom 30 to 50 minutes, up to 4 hours, with inter vals
of 1 to 3 hours between eruptions (Bryan, 2008). During an eruption, the
spinning water in the crater reaches heights between 1 to 10 m.2.2 Great Fountain
Geyser Great Fountain Geyser is a fountain-type geyser located at Lower Geyser
Basin (Figure 1a). According to Bryan (2008), once an eruption begins, violent
surges of boiling water and steam leave the ~ 4.8 m vent and reach heights of
up to 45 m for several minutes. The activity then pauses and resumes after a few
minutes. This behavior is often repeated four times within a 45 – 120 minute
interval with surges decreasing gradually in height. Bryan (2008) and Johnson et
al. (subm) observed that Great
Fountain’s eruptions occur every 8 to 17 hours.
2.3 Lone Star Geyser
Lone Star Geyser, located in Third Basin (Figure 1a), is one of the biggest in
Yellowstone with a 2.7 meter-high geyserite cone and nearly vertical sides. This
cone-type geyser has eruption intervals often close to 3 hours. The main er uption is
preceded by a minor play 25 to 35 minutes before (Bryan, 2008). The activity consists
of a 30- minute 14-m high eruption that starts with continuous splashing gradually
transitioning into a jet of a water-steam mixture, and eventually into a pure-steam jet
towards the end of the eruption.
WHAT ARE SOLAR WATER HEATERS
Solar water heaters are a form of solar power. They consist of a collector, which
collects solar energy, and have an insulated storage tank, which stores hot water. Solar
water heaters can be of two main types, depending on the collector system, the first
type is the Flat Plate Collectors. In this, the flat plate collectors absorb the solar
radiation, they are made up of an insulated outer metallic box, which is covered by a
glass sheet on the top. Inside, the blackened metallic absorber sheets have built in
channels, or riser tubes, which the function of carrying water. The solar radiation is
absorbed by the absorber, and the heat is transferred to the flowing water.
The second type is the Evacuated Tube Collectors. The collector is constructed
through double layer borosilicate glass tubes, these are evacuated for the purpose of
providing insulation. The inner tube’s outer wall is coated with selective absorbing
materials. This assists in the absorption of solar radiation, and thus the heat is
transferred to the water, which is flowing through the inner tube.
Using solar water heaters will help to benefit the environment, as the technology is
quite mature today, having undergone much research. People can stop using
conventional forms of energy for heating water in factories, residential homes, and
other commercial establishments. The market for solar water heaters, too, has been
steadily increasing. Solar water heaters can provide hot water at temperatures of 60-
80 degrees, for restaurants, hospitals, homes, etc. The heaters which have a capacity
of 100-300 liters, are quite suitable for domestic applications. However, one can
install the larger systems in guest houses, hotels, etc.
So what about the fuel savings? Well, you’ll be astonished to know that a solar water
heater of 100 liters capacity can replace even an electric geyser, and 1500 units of
electricity are saved every year! And what about the environment? The solar water
heater (of 100 liters capacity) prevents emission of 1.5 tonnes of carbon dioxide
annually. The life of a solar water heater is approximately 15-20 years. The beginning
investment for a solar water heater is somewhat high, initially, compared to more
conventional fuel alternatives, but the returns on the investment are quite good,
because prices of conventional forms of energy are rapidly rising. The period of
payback, however, depends on many factors. These are the pattern of utilization, the
fuel replaced, and the site of installation.
Solar water heaters are really easy – they are made up of thermal collectors which are
covered with dark glass, and a fluid system that allows the heat to move from the
collector to the point of usage. Lastly, there is a reservoir that stocks the heat water for
its use. Such systems can be used to heat swimming pools, or for domestic purposes.
Solar water heaters use solar power to give thermal energy in order to provide hot
water. Such systems can save lots of energy, as well as cutting down on utility costs.
Plus, the energy produced is absolutely clean. Even in the northern climate, with a
cold winter sun, solar water heaters can bring a 40% reduction in the electric bill.
SAFETY INFORMATION
Please read carefully to prevent serious accidents or injury.
The Geyser-R Heat Pump Water Heater must be installed in the accordance with
Local and National codes as well as the installation instructions in this manual. Before
beginning the installation, carefully read the entire manual and check the local, state,
and national codes regarding building, electrical, and plumbing installations, or check
with your local authorities for clarification of these codes. Failure to install the
Geyser-R in accordance with these codes and the installation manual may result in
property damage, bodily injury or death.
Disconnect all power before installing or servicing the Geyser-R.
There is a discharge fan located on the unit. Extreme caution must be exercised to
ensure that any foreign objects including fingers and hands remain clear of the fan
area.
Do not stand, sit or place any objects on or beside the unit (clearances are stated in
the installation manual).
Do not allow children to play on or near the unit.
Make sure all power is disconnected and shut off before moving the unit.
Cover should not be removed with power on.
Internal components may be HOT. Please allow sufficient time for the unit to cool
completely before touching any internal components.
Ensure that the power receptacle for the Geyser-R is rated for 115 V. and at least
15 A.
Ensure that the electrical supply has a properly rated fuse or breaker protection
rated for at least 15 amps. It is suggested to use a dedicated outlet.
Always wear eye protection during installation.
Unit weight is approximately 70lbs. All lifting should be done with the handles
located on the side of the Geyser-R. Proper lifting should be used in the moving of
the unit.
The Geyser-R must NOT be connected to an electric water heater with heating
elements larger than 240/5500 watts.
SYSTEM REQUIREMENTS
The Geyser-R should only be installed in a dry/covered location. The Geyser-
R is not designed to be installed outside where it can be exposed to adverse
weather condition. The ambient air temperature in the installation area should
not drop below 50°F (10°C). The cubic area of the space needs to be 1,000
cubic feet or greater for proper air flow and to avoid excessive cooling of the
area. The Geyser-R can be installed in attics garages, or basements provided
the above criteria are met for proper installation.
The Geyser-R connects to a typical household outlet, 115V, 15 Amp. While
the device requires approx. 12 Amps momentarily upon power-up, the device
draws 5-8 Amps during normal operation. It is recommended that a dedicated
15 Amp Circuit be used to power the Geyser-R. The Geyser-R is
recommended for installation on electric water tanks of 40gallons (151.4
liters) or greater.
A drain must be available to accommodate condensate generated during
operation of the Geyser-R. In high humidity environments, the Geyser-R is
capable of generating as much as 50 pints (24 liters) per day. The condensate
can be routed to a floor drain, sink, the house waste line, or to the outside by
way of the drain hose (provided).
Check with the codes in your area for the proper way to dispose of the
condensate. A condensate pump may be required (not included).
Most electric water tanks utilize two heating elements, one at the top of the
tank and one at the bottom. The heating element at the top of the tank is called
the quick recovery element. This is designed to heat water at the top of the
tank if the temperature of the tank falls below the set point of the thermostat.
The lower element provides most of the heating in a typical water heater.
The Geyser-R replaces the lower element in operation and provides the
majority of the heating requirements. The upper element is left on at the
temperature you set it, and will only engage if there is a need for quick
recovery. Therefore in normal operation the Geyser-R will provide all the hot
water needed and the top element will not run.
The Geyser-R will remove moisture from the air. It is an efficient
dehumidifier and many have found that the unit provides all the necessary
dehumidification for the space the Geyser-R is located.
Moisture may occasionally cause frost to form on the evaporator. When the
frost builds up, the Geyser-R will go into a defrost cycle. This could occur as
often as every two hours in a cold humid environment. While in the defrost
mode, a period of up to 6 minutes, the fan will continue to run and the tanks
lower element will provide heating for the tank, when the defrost cycle is over
the Geyser-R will resume heating the water.
CHAPTER 3
LITERATURE REVIEW
2.1 BACKGROUND
Compared with the popular conventional vapour-compression and absorption
refrigeration, the water boiling has a few significant advantages cover: 1) large
capacity of energy saving and carbon dioxide emission reduction because no energy
intensive compressors exist in water boiling systems; 2) more environmental friendly
cooling technology because only water participate in the cooling process rather than
pollutant geyser; 3) more simple in terms of structure, construction, and control
strategies.
Most of conventional air conditioning systems are based on vapour-
compression and absorption refrigeration cycles, which are mature technology and
have been widely applied in residential and commercial buildings. The performances
of vapour compression and absorption refrigeration systems are stable and sufficient
to provide cooling for buildings. However, they are energy intensive refrigeration
technologies owing to using the energy-consuming compressors, fans and pumps. The
typical values of Energy Efficiency Ratio (EER) for some typical refrigeration cycles
are summarised in Table 2-1. Due to no compressors involved, the EER values of
water boiling systems are much higher than those of conventional refrigeration cycles.
The energy consumption of water boiling systems is usually 30-50% that of
compression air conditioning system with the same capacity.
Thus, the EER value of an water boiling system is 2-3 time that of a typical
Vapour-compression system.
The current mainstream geyser employed in water boiling systems is HCFCs
(such as R-22) and HFCs (such as R-134a, R-410A). HCFCs and HFCs have large
global warming potential (GWP) and they can trap heat more effectively than carbon
dioxide. Water boiling, however, utilises the latent heat of water evaporation to
provide cooling instead of using harmful geyser and thereby has a great potential of
slowing down global warming.
As two major types of water boiling, direct water boiling (DEC) adds moisture
to room air, which causes discomfort and health problems. Indirect water boiling
(IEC) lowers air temperature and avoids adding moisture to the air, but it limits the
temperature of supply air to some degrees (2 to 5oC) above the wet bulb of the
outdoor air (usually 40-60% wet-bulb effectiveness), which is too high to perform air
conditioning of buildings. Especially for the regions with humid climates, the IEC
systems usually have poor performances. To solve this, a pre-dehumidifier, direct
expansion (DX) compressor or chilled water coil can be combined together with the
IEC modules to form a hybrid system, which can provide a low supply air at a lower
cost than conventional air conditioning system and can be applied in various climate
conditions. The potential market of the IEC systems can be very large as long as the
existing technical difficulties/barriers can be solved, i.e., relatively low effectiveness,
high initial costs and large size occupations, etc.
By studying the relevant literatures, some basic knowledge, e.g. evaporative
medium, apparatus types, work principles, performance and characteristics of various
water boiling systems, have been identified. Then performance evaluation standards
of IEC systems have been indicated, which will be used in comparing the
performances of different types of evaporative systems. The previous research works
conducted on the IEC-related systems are too scattered and ambiguous to identify the
focuses of research and technical problems surrounding the IEC technology.
Therefore, it is very necessary to sort out the current developing status of the water
boiling technology, remaining difficulties or problems and technical barriers of
practical applications by analysing the related R&D and application projects of IEC
systems.
CHAPTER 4
EXPERIMENTAL SETUP AND OBSERVATIONS
INSTALLATION PARTS
The Geyser-R comes with the following installation kit:
Qty Description
1 4”x ¾” Nipple 2 ¾” Tee 1 Dip tube 2 ¾”FH x ¾” FIPS, with washers. 4 ¾”PEX x ¾” MIP 1 Teflon Tape 1 Red Wire nut 1 Strain relief 6’ Condensate tubing
YOU WILL NEED TO PROVIDE THE FOLLOWING
COMPONENTS TO COMPLETE THE INSTALLATION:
¾” Pex tubing.
Pex tubing crimps ¾”
Armaflex ¾” insulation (not split Rubatex)
Optional: 2 shut-off valves
Furthermore, a transfer pump is recommended to drain the tank.
This installation method is designed to bring the most efficiency for the
system. Deviating from the following installation procedure will affect
the efficiency of the unit. Deviation from the installation method could
also damage the unit and void the warranty. PLEASE read and follow the
installation instruction carefully.
It is recommended that the Geyser-R be installed as close as possible to
the water heater. We recommend 4 feet if possible. This will ensure the
most efficiency with the least amount of heat loss through the piping.
INSTALLATION OF THE GEYSER-R
Note: The following installation instructions cover the installation of the Geyser-
R in conjunction with an electric water heater. Alternate water tanks may
require an alternative installation method not covered by this manual. It is
recommended that you contact Nyle Systems office (1-800-777-6953) and speak
with technical support to see if the Geyser-R can be used in a particular
application other than an electric water heater.
Survey the area where the Geyser-R is to be installed. Make sure the
area is clear of obstructions, clear of debris, and clean of significant
dust and dirt that can get into the unit or clog the filter.
Area should be at least 1,500 sq ft of open space.
Ambient air temperature should be at least 50°F (10°C). Temperatures
lower than this will cause the unit to defrost constantly and reduce the
efficiency. If the temperature in the space gets lower than 50°F
(10°C), it is recommended that the unit be shut off until a constant
temperature above 50°F (10°C) can be maintained.
When choosing the placement of the Geyser-R, make sure the fan is
not blocked or close to a wall or other object that would inhibit air
flow.
The Geyser-R should be placed on the floor or set on vibration
isolation pads. Make sure the unit is higher than the drain and the
drain line has an unobstructed path to the drain.
You can install the unit in an elevated position if desired. Make sure
the unit is secure and that the piping is not kinked or restricted in any
way. The unit should not be installed higher than the top of the water
heater.
Piping should be kept to a minimum and as short as possible to
minimize heat loss. 4 feet is the recommended length.
Check the overall condition of the existing water heater.
Make sure the drain is easily accessible.
Be sure shut off valves are in good condition and are in working order.
If unit is being installed in an attic it is recommended that both hard
and soft foam be placed on the joists to absorb any excess vibration.
Make sure there is an 115V outlet in close proximity to where the unit
is going to be installed.
DO NOT installs the Geyser-R with an extension cord of any size.
INSTALLATION INSTRUCTIONS
Turn off all power to the water heater at the circuit breaker in the electric panel.
Plumbing Installation
Turn off the cold water inlet at the service valve above the water heater.
Open one or more hot water faucets in the house to relieve the water pressure in the hot water tank; leave these faucets open to allow air to freely enter the tank during draining.
Drain the tank completely.
Alternate Installation of the Geyser-RSome tank manufacturers use a molded construction that does not allow for a dip tube to be
inserted into the bottom of the tank. In this case we recommend the water be heated by the
Geyser-R, pulled from a “Tee” on the cold water supply at the top of the tank. The hot water
that exits the Geyser-R is to be returned to the tank through a “Tee” at the drain valve.
Note: The following installation requires the cold water inlet to the water tank to be cut and a
tee or connector assembly will need to be soldered in place. Nyle Systems recommends this
installation be done by a licensed plumber.
When the supplied dip tube isn’t used in the system, the following installation method is
suggested:
CHAPTER 5
CONCLUSION
This study has developed a new indirect evaporative cooler for buildings. The
observations reiterated the usefulness of Evaporative Cooling. Even though, the
assumptions were purely arbitrary the results have been very optimistic. The cooling
effect produced by the constructed system has shown us that evaporative cooling is
not just a cheaper but also a effective process of cooling than Compression based
cooling.
The comparison of IAC with Air Conditioning system may not yield desirable
cooling results but, glancing beyond this basic requirement, its various other
advantages over an Air-Conditioner makes it a very credible and lucrative choice.
Above all, the entire process is eco-friendly and can be viewed as pollution free
option of conditioning.
REFRENCES
1. Anderson, W. M. (1986). Three-stage evaporative air conditioning versus
conventional mechanical refrigeration, ASHRAE Transactions, vol. 92, pp.
358-370.
2. Çengel, Y. A. and M. A. Boles (2007), Thermodynamics: an engineering
approach,
New York, McGraw-Hill Higher Education.
3. Coolerado (2006), Coolerado HMX (Heat and Mass Exchanger) brochure, C.
Corporation. Arvada, Colorado, USA.
4. Guo, X. C. and T. S. Zhao (1998), A parametric study of an indirect
evaporative air
cooler, International Communications in Heat and Mass Transfer, vol. 25, pp.
217- 226.
5. Hausen H. Heat Transfer in Counter Flow, Parallel Flow and Cross Flow. New
York: McGraw-Hill, 1983.