Solar Domestic Water Heating – How to get Started · 2016-10-20 · Solar Energy Project...

Solar Energy Project Development Specialists 1

Solar Domestic Water Heating– How to get Started –

Gordon Howell, P.Eng.Phone: +1 780 484 0476E-mail: [email protected]

©1995-2008

Trimline Training Centre

2008 April 10 and 17


Questions…?

Course Contents1. Introduction to course2. Context to solar heating3. Energy, solar energy – the resources, the technology,

how it works4. Mounting angles5. Solar equipment, components6. Operating configurations, installation locations7. Costs, economics, rules of thumb sizing8. Local examples of solar DW heating systems9. Getting your own solar DW heating system, how to find

contractors, how to buy10. How about solar space heating?

Next


Intro: My Goals…

To empower you to get ready for the energy and environmental issues coming upon us

To help you understand how solar heating can be used to heat your household hot water

To help you take next steps in using solar water heating– to reduce your natural gas bills, – to reduce your environmental footprint, – to increase your energy security– to leave a legacy… so you can look your grandkids in the eye!

We have done a lot of research for you and have assembled it here in one place

I'd put my money on the sun and solar energy. What a source of power! Thomas EdisonI hope we don't have to wait 'til oil and coal run out before we tackle that. (1847–1931)


Intro: Me! ––

I am a solar system project developerI am not an equipment supplierI have no vested interest in any technology

My interest is that you choose wisely– with your eyes wide open– based on the facts and whether it is right for you

or not.


Intro: Your Goals?

What are your goals?

What do you want to get out of the course?

What do you want to achieve by using solar heating?

The Earth provides enough to satisfy every man's need, Mohandas Karamchand Gandhi…but not every man's greed. (Mahatma) India


Intro: What the Course Does…

NOT a design course… This is an introductory course

Gives you familiarity with the technology and its terms, concepts, components and costs.

Gives you space to ask questions and get answers right away … or I can find answers for you.

Dispels mis-understanding and myths about solar energy

Helps you understand how to buy a solar water heating system with confidence

FAST – GOOD – CHEAP… you are only allowed to choose two of them!


Intro: Solar Water Heating

– What is it?

Solar water heating systems produce heat from the energy in sunlight.

Solar collectors convert the sun’s energy to heat. They heat water or glycol, which is then pumped to a storage tank for use in the building.

Most commonly used for heating household domestic water.

Can be used for heating swimming pools and building spaces.– The technologies are very very similar, but…– the application has radically different heating requirements throughout the

year.


How does it work?What equipment do you need?

What can you expect from it?

How much does it cost?What is the price of its heat?How does this compare with other prices?

How to put it on your house? – Location, tilt, orientation– Finding a contractor

Solar domestic water heating systemEdmonton

Intro: Course Focus

Natural gas utility companies:– This course is not about being

against them.– They have had a critically important

role in helping society grow, by providing affordable energy and by showing us how to use it in a very safe way.

Be the change you want to see in the world.Mahatma Gandhi, India


Context: Energy Efficiency vs. Adding Energy…

Solar energy, wind energy, and geothermal heat pump energy options:– Do NOT reduce your energy consumption!– Instead they substitute your heating source from natural gas over to the sun…

Energy efficiency option:– Cheapest, most important, highest return on investment and shortest payback

option…– But it is emotionally boring

Solar, wind and geothermal all have much higher costs and longer paybacks than energy efficiency

– It is exciting and something you can brag about to your friends…

Climate change: Gordon Campbell The costs of doing nothing are getting higher every day. BC Premier


Context: Why Use Solar Heating?

Utility Costs

Reduce heating bills – you pay for solar heating equipment up front

Reduce vulnerability to up and down heating prices

Environmental FootprintReduce how much air pollution you cause from burning natural gasIncrease the reserve of natural gas you leave for the next generation

Political will arises from personal momentumWe need to be the leaders to our governments and corporations.


Context: Why Use Solar Heating?

Business OpportunityServe the growing public interestServe the multi-billion $ world markets

Social OpportunityProvide the leadership that we needEncourage the government to facilitate it instead of developing policies that block it

The superior man seeks what is right; Confuciusthe inferior one, what is profitable.


Proven technology – thousands of systems across Canada

Can provide energy security and independence

Inflation-proof

Political-proof

No noise

No emissions

Low or zero Low or zero maintenance costscosts

Low or zero Low or zero operating cost

Extends the lifetime of our dwindling natural gas resources

Context: Benefits of Solar Heating…

The dependence on fossil fuels is a major barrier The New Economics…to improving human well-being around the globe. Foundation


Purchase costs are high

Not a well developed supply or installation chain

Not a lot of broad-based experience in Canada

Has to compete with highly subsidized natural gas

Little interest by the government in developing technology assistance programs

Code barriers

Context: Challenges with Solar Heating…

When one tugs at a single thing in nature, John Muiryou find it attached to the rest of the world. Conservationist


Other Countries…

Tens of thousands of new solar water heaters are installed worldwide each year.

In Austria, one in seven homes uses solar water heating.

In Germany, one in 16 homes uses solar water heating.

Spain legally requires solar hot water systems in all new buildings.

Some 80% of solar water heating systems are manufactured and installed in China.

We are consuming the resources of our planet at such a rate Prince Charles that we are, in effect, living off credit and living on borrowed time. of Windsor


Questions…?




Every great movement must experience three stages: John Stuart Mill…ridicule, discussion, adoption.

Next


Background: What is Energy? – The basics

The superior man seeks what is right; Confuciusthe inferior one, what is profitable.

Energy is the ability to do work:– Equals a force exerted over a distance– Measured in "Joules" or "J“.

Heat is a form of energy.

Electricity is NOT energy, it is free electrons– but the energy that is in them can be extracted and put to work– thus electricity is usually represented as energy.

Light is NOT energy, it is photons– but the energy that is in them can also be extracted and put to work.


Background: What is Power? – The basics

Power is the rate at which energy flows!!!Measured in Joules per second, which we call a "watt", or "W".

Heat flows from one place to another through:– Conduction – such as through a metal object– Convection – which causes hot air to rise– Radiation – which transports light energy from the sun to the earth

Heat flow is caused by a temperature difference – whenever you have a temperature difference

then you will have a flow of heat

Our responsibility is to retain what we treasure because Frederick Steiner we are merely guests on these spaces of earth which we inhabit. "Living Landscape"


Question: What is Alberta's most abundant energy resource?

All energy is Some energy is black, It's your choicenot created equally. some is green. …but everyone's consequences.


– Our Most Abundant Energy Resource

What is the use of a house...if you haven't got a tolerable planet to put it on? Henry David Thoreau, America

Alberta: The Solar Province

14 hours of sunshine = all our fossil energy resources in 2001!

Alberta's sunshine is over 300 timesmore than our fossil fuel resources.


Solar energy – the energy contained in

the photons that comprise sunlight

Sunlight is– visible light– electromagnetic radiation (as is all light)– non-ionizing radiation (as is all light)– short-wave light (different from radio waves or

microwaves)

All energy has come from the sun!– some of it has just been stored for a time!

It may seem impossible to imagine that a technologically advanced society could Elizabeth Kolbertchoose, in essence, to destroy itself, but that is what we are now in the process of doing. New Yorker

What is Solar Energy?


Red Deer'snewest net zero electricity home

Okotoks swimming poolsolar heating

Okotoks 52-home solar heated subdivision

Cochrane High School solar power

Photo Credit: Gordon Howell

Photo Credit: SPS Energy

Photo Credit: Gordon Howell

Solar Energy– where can it be used –

Anything that uses electricity

Space heating

Water heating – for domestic water, pools

Industrial and commercial process heating

Cooking

Daytime illumination


How do we use Solar Energy?

Need to collect it (both for electricity and heating)

Need to store it – but only if we have enough to spare for times when we need it

Need to deliver it to the appliances and the house

Need to protect ourselves from it! (…overheating)

You cannot teach a man anything, You can only help him discover it within himself. Galileo

SourceCollector

Storage

UsageDelivery

Recovery


Aurum Lodge, 2004

Solar Heating for Residential Domestic Water

School north of Cochrane, 2007

Sally Anne Rice home, Edmonton, 2007

Tim Belec home, Pigeon Lake, 2007

Tim Belec home, Pigeon Lake, 2007


Restaurant, 16 Ave N, Calgary, 2002

Best Western Hotel, Kelowna, 2003

Drake Landing Solar Community, Okotoks, 2006

Recreation Centre swimming pool, Okotoks, 2003

Photo Credit:Swiss Solar Tech

Solar Heating for Commercial

Process Water


Solar heating and solar electricity

are NOT the same…

Solar heating – A dark surface sitting in the sunshine– Water or air runs past the solar

heated surface carrying heat to the building.

Solar electricity– A semiconductor device like a computer

chip– Photons bump electrons out of an atom.– Wires carry the electrons away.


How many solar panels do you see here?32

2

1

What words do we use?

Solarwall ventilation air pre-heating system

Solar domestic water heating

system

Solar electric generating system

Direct gain passive solar space heating

windows


What words do we use?

Solar panels

Solar heating:– thermal collectors

Solar electricity:– photovoltaic modules

Cities grow great when old men plant treesin whose shade they know they will never sit.


Solar Domestic Water Heating System - Concept

© 2006-2008 Trimline Design Centre

Sunlight and its energy

Collectors

Piping, pumps,valves,control, flow meter

Storage tank, heat exchangers

Cold water source

Hot water usage

The only thing lacking is some form of leadership … to focus the public will to make it happen.

Lots of configuration optionsLots of component types


Solar Water Heating – Major Components

SolarSolar controllercontroller (one type)(one type)

HeatHeat exchangerexchanger

PrePre--heatheat water tankwater tank

PipingPiping connectionsconnections

SolarSolar collectorscollectors

(~$1000 (~$1000 eacheach))

Where there is a will, there is a way…It's not about economics. It is about a will.


Solar Water Heating – Controller Turns On Pump

In In thisthis exampleexample, a , a solarsolar pumppump isislocatedlocated on top of the on top of the heatheatexchangerexchanger;;

The The controllercontroller sendssends a signal to a signal to the the pumppump to to turnturn onon……


Solar Water Heating – Liquid is CirculatedGlycol (antiGlycol (anti--freezefreeze) ) isis thenthencirculatedcirculated betweenbetween the the heatheatexchangerexchanger and the and the solarsolarcollectorscollectors……


Solar Water Heating – Liquid is Heated

WithinWithin the the collectorscollectors, the glycol , the glycol absorbsabsorbs the the solar heatheat……

The The collectedcollected solarsolar heatheat circulatescirculatesback to the back to the heatheat exchangerexchanger…… 1


Solar Water Heating – Heat is Transferred

Cold water Cold water isis circulatedcirculated betweenbetween the the solarsolar tank and the tank and the heatheat exchangerexchanger……

The The heatheat exchangerexchanger transferstransfers the the solarsolar heatheat intointo the waterthe water……

The The heatedheated water water returnsreturns back back intointothe the solarsolar tank.tank.

1

2


The The heatheat collection collection processprocessoperatesoperates over the over the wholewhole dayday……

The The solarsolar tank water tank water heatsheats up up throughoutthroughout the the dayday……

UntilUntil the the wholewhole solarsolar tank tank isis filledfilledwithwith hot water!hot water!

Solar Water Heating – Hot Water is Stored

2

1


WhenWhen hot water hot water isis drawndrawn off for off for usageusage……

SolarSolar heatedheated water water flowsflows intointo the the gasgas or or electricelectric booster tankbooster tank……

And cold water And cold water fromfrom the city the city isisdrawndrawn intointo the the solarsolar tanktank……

Solar Water Heating – Delivery to You

1

23


Questions…?




Next


The solar window:Where most of the sun's energy comes from…

Path of the sun across the sky

All electrons are Some electrons are black, Your choice…not created equally. some are green. but everyone's consequences.

Sun's pathDecember 21 Sun's path

June 21

NorthSouth

East

West

3pm

10am


The Energy in Solar Radiation

= 3.6 sun-hours/day in Edmonton

… ok, but under what conditions

– Tilt? horizontal, 6/12 tilt, 53 tilt, vertical?

– Orientation? north, south, east, west?

– Conditions? maximum, average

– When? summer, winter, yearly?


Solar Myth:Solar needs to be perfectly orientated

in order to work at all!

precise optimum tilt and orientation to collect maximum solar energy

wide range of angles to orient and tilt solar equipment and still not be too far off maximum

All heat is Some heat is black, Your choice…not created equally. some is green. but everyone's consequences.


The maximum annual solar energy production occurs at around a 53° tilt.If your goal is to maximise this, your tilt angle can be from 18° to 80° and still be within 10% of the maximum.

Optimum Annual Solar Tilt AngleEdmonton

% of energy from optimum annual tilt angle

-30%

-25%

-20%

-15%

-10%

-5%

0%0 13 23 33 43 53 63 73 83 90

Horizontal Vertical

4.8

3.6

4.0

sun-hours/day

= kWh/m2/day


Optimum Winter Solar Tilt AngleEdmonton

% of energy from optimum winter tilt angle

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%0 13 23 33 43 53 63 73 83 90

Horizontal Vertical

3.8

Sun-hours/day

1.0

3.4 3.75

The maximum winter solar energy production occurs at around a 83° tilt.If your goal is to maximise this, your tilt angle can be from 50° to 90° and still be within 10% of the maximum.

Snow?Reflection from snow fields?


% of energy from optimum annual orientation angle

If the goal is to maximise the annual energy production, which occurs at a due-south orientation angle, you can locate the orientation 45° either side of south and still be within 10% of the maximum.

Edmonton

-12%

-10%

-8%

-6%

-4%

-2%

0%230 220 210 200 190 180 170 160 150 140 130

Optimum Annual Solar Orientation AngleSW SESouth

SW South SESSESSW


% of energy from optimum winter orientation angle

If the goal is to maximise the winter energy production, which occurs at a due-south orientation angle, you can locate the orientation 30° either side of south and still be within 10% of the maximum.

Edmonton

-30%

-25%

-20%

-15%

-10%

-5%

0%230 220 210 200 190 180 170 160 150 140 130

Optimum Winter Solar Orientation AngleSW SESouth

SW South SESSESSW


Solar RadiationSolar RadiationHorizontalHorizontal

Peak daily sun-hours

0.0

2.0

4.0

6.0

8.0

1 2 3 4 5 6 7 8 9 10 11 12 Annual

0°, horizontal

Months

If the world is saved, it will be saved by people with changed minds, Daniel Quinn… people with a new vision. author


Solar RadiationSolar RadiationHorizontal and 27Horizontal and 27°

What is the use of a house... if you haven't got a tolerable planet to put it on? Henry David Thoreau, America

0.0

2.0

4.0

6.0

8.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14

0°, horizontal

27°, 6/12 roof pitch

Months

Annual



Solar RadiationSolar RadiationHorizontal, 27Horizontal, 27°, 53°

You cannot teach a man anything, You can only help him discover it within himself. Galileo

0.0

2.0

4.0

6.0

8.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14

0°, horizontal


53°, latitude

Months

Annual



Solar RadiationHorizontal, 27°, 53°, Vertical

0.0

2.0

4.0

6.0

8.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14

0°, horizontal


53°, latitude

90°, vertical

Months

Annual


In many ways our future is passing us by, Gary Lamphier… and our energy riches may one day look like fool's gold. Edmonton Journal


Questions…?




Next

Bringing you a prosperous future American where energy is clean, abundant, reliable, and affordable. Dept of Energy


Components

Collectors– unglazed, glazed, evacuated tube

TanksHeat exchangers

– in tank and side-armPumps

– centrifugal and positive displacementControls

– differential, digital, solar intensityPiping, fittings

– only copper, bronze, brass, stainless steelHeating fluid

– glycol, water

I am what I am – not because of what I should be or have to be……but because what I am made to be.


Glazed flat-plate collector

– commercial,industrial, residential

– most common

Evacuated tube collector

– high-temperature process heating

Unglazed flat-plate collector

– primarily used inoutdoor pool heating

Enerworks

Solar Water Heating CollectorsSolar Water Heating Collectors


Unglazed Flat-Plate Collector

Have no insulation and no glass coverTypically used for low temperature and/or seasonal heating loads


Unglazed Flat-Plate Collector

Good applications:– Swimming pools– Aquaculture– Car and truck washes

If you're not in favour of zero waste …how much waste are you in favour of?


Solar Pool Heating

Unglazed collectors

Controls and valves


Unglazed Flat Plate CollectorsAdvantages

– Very low or zero maintenance costs– Very low operating costs– Can be used directly with chlorinated pool water– Least expensive– Easiest to install

Drawbacks– Can only be used in summer-like outdoor temperatures– Least efficient– Yearly draining is required– Not protected from the environment– Completely plastic and degrades over time

Text Credit: Trimline Design Centre

Never doubt that a small group of thoughtful and committed citizens can change the world.Indeed, it is the only thing that ever has. +Margaret Mead, Anthropologist

Solar Energy Project Development Specialists 55Photo Credit: Trimline Design Centre

Glazed Flat Plate Collectors

Contains frame, glazing, absorber, piping, brackets, insulation, gaskets, screws

Made of glass or polymers, aluminum, steel, copper, fiberglass or isocyanurate, EPDM

Typically for residential and commercial applications


GlazingLets light in, reduces heat

loss, like a greenhouse

AbsorberConverts sunlight

into heat

InsulationReduces heat losses

FrameProtects the collector

Fluid circuitHarnesses heat from

absorber

Solar Water Heating Collectors – Concept

You must skate to where the puck is goingnot to where it is now. Wayne Gretzky


Uses selective surface coating on the absorber plate– Painted black: 90% absorbing, 30% re-emitting!– Selective surface: 94% absorbing, 5% re-emitting!

Glazed Flat Plate Collector Details

– reduces reflection, ensures glass safety


Flat Plate Collectors – Mechanical Design

Standard internal headers – headers are parallel to collector case

Can be used for drainback or no-drain systems.Need to be tilted if used in drainback systems.

Internal headers specially designed for drainback – headers are already tilted.

Can be used for drainback or no-drain systems.

No need to tilt the collectors.



Flat Plate - Glazed

Application– Used for domestic water or space heating, pools

Advantages– Very low or zero maintenance costs– Very low operating costs– Permanent installation – withstands the environment– Can be used throughout the year– Can be used for solar cooling at night

Drawbacks– Less efficient than an evacuated tube in extreme cold

weather– More wind drag than evacuated tube (doesn’t matter)

Our greatest desire is our greatest delusion unlessour greatest desire is to find out what life is all about…


Evacuated tube collectors

Single glass tube with an Single glass tube with an internal plate absorber.internal plate absorber.

oror

Double glass tube with Double glass tube with an integral coated inner an integral coated inner glass curved absorber.glass curved absorber.


Evacuated tube collector – heat pipe


Apricus ETC

cut-away


Apricus ETC Operation


Evacuated TubeApplications

– Used for domestic water or space heating, pools

Benefits– Very good at collecting heat in cold and cloudy

conditions– Very low or zero maintenance costs– Very low operating costs– Permanent installation – withstands the environment– Can be used throughout the year

Drawbacks– Higher cost for extra efficiency– Limited design function – tubes must be mounted

near to vertically– Expensive – $2500 for 30 tubes– Concern about durability– Snow cover for longer time periods– Cannot be used for summer cooling (except if you

use an absorption chiller)



Failed ETC tubes

ETC tubes need to maintain their vacuum in order to operate efficientlyConcern about durability

Vacuum is good

Vacuum has failed


Residential-Sized Solar Heat Storage Tank

Storage tank with heat exchanger inside

Pump controller

Solar circulation pump

Often also has a Often also has a drainbackdrainbackreservoir and a flow meterreservoir and a flow meter

We can't solve problems by using the same kind of thinking we used when we created them. Albert Einstein


Storage Tanks

Stores hot water so that it can be used at a later date.

Used to transfer heat from solar piping to domestic water.

Can contain heat exchangers.

Can be:– pressurized or non-pressurized– made from metal, fiberglass or polymer materials– mounted above or below ground level

Various sizes from 50 litres to 5000 litres or larger.



Heat Exchangers

Coil inside the tank

Transfers heat from one fluid “flow”or loop to another

– Solar loop to storage loop– Solar fluid to drinking water

Protects drinkable water from glycol and stale water


“side-arm”


Circulation Pumps– Centrifugal

AC Pump AC Pump

DC Pump

Pumping fluid in the solar loop and space heating loop.

Allows fluid to flow both directions through the pump when stopped – critical for drainback systems.

Fluid flow rate can be controlled without causing damage to the pump. Typically 1 to 2 litres/minute per collector.

No chance of over-pressuring fluid loops or storage tank limits.

Requires in-line check valve to prevent thermo-siphoning.

Built-in motor protection for long life. Typically 10-15 years.



Circulation Pumps– Positive

Displacement

Typically used for AC, DC and/or direct PV driven systems.– PV system - variable speed to match flow rate with solar intensity.

– AC or DC - fluid flow rate cannot be independently controlled to match collector requirements.

Needs pressure relief valve in fluid loop to prevent possible over-pressure condition.

Prevents thermo-siphoning conditions due to internal pump design.

Cannot be used for drainback systems.



Control using Collector-Tank Temperature Difference

…the circulatingpump is onlytriggered

when the collectortemperature is higherthan the cold water temperature.


System Controllers– analogue (delta T)

Typically controls one pump only, based on temperature difference.– Operates the solar loop pump only.– No multiple pump control.

Limited to low temperature sensing only.

No data logging functions.

AC power source.

AC pump control.



System Controllers– digital


25

30

35

40

45

50

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52

Header Temp.

Typically based on a microcomputer– is programmable, very flexibility.

Additional features can include:– multiple pump control such as for double-pump systems;– real time data logging – to see system performance; and– web access and interface for remote data logging.

Selectable temperature sensors to allow for temperature monitoring up to 500°C.

Power source can be AC or DC.

25

30

35

40

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52

Tank Temp.


Control using Solar Energy Levels

…a PV module produceselectricity for a DC circulating pumpwhen the sunshines.

Solar PV module


Flow Meter

Allows:

– system flow rate to be properly set and monitored;

– visual monitoring of system fluid level; and

– visual monitoring of system fluid condition.


Education’s purpose is to replace an empty mind with an open one.Malcolm S. Forbes


Questions…?




Next

Treat the Earth well. It was not given to you by your parents.It was loaned to you by your children. Kenyan Proverb


Glycol-Based Configuration– Advantages

Immune to freezing.

Can run piping without concern for level or plumb.

Easy for the do-it-yourself person to install.

Text Credit: TrimlineDesign Centre

In a glycol-based configuration, typicallyglycol is pumped through the system and stays in the collectors and the lines, evenduring freezing and stagnating conditions.

Solar PV module


Glycol-Based Configuration– Special Design Considerations

May need an external heat dump for excess heat.– When the controller stops the pump due to the storage tank

temperature set point, the system still continues to heat the glycol in the collector.

– When the glycol boils it turns acidic and sludgy, and eats away at all the copper piping and solar collector manifolds. It needs to be replaced.

– The continued heating raises the solar loop pressure and could cause leaks in the system.

New Enerworks solar thermal collectors (www.enerworks.com) have solved this issue.


Working together to reduce our impact on the land, air & water is not only the responsible thing for us to do as corporate citizens – it’s also the right thing for the future of our businesses.

Suncor CEO Rick George


"Drainback" Water-Based Configuration

In a drainback system, wateris only pumped up to the collectors when enough solarenergy is available to heat it.

Otherwise, the collectorsremain empty – such as atnight and during freezing and stagnating conditions.

1

2

3


Drainback Configuration– How is it different?

Solar loop circulates water– from storage tank to solar collectors to be heated,– then to the drainback tank,– may need to use distilled water because there are no minerals in it.

Some city water can make algae in the system in a year.

Tank loop circulates water– from drainback tank,– to the storage tank, which stores the heat for future use.

When storage tank is full of hot water, the pump stops and the water drains back to the drainback tank due to gravity.

Drainback tank:– essential for a drainback system to work,– maintains an air buffer to allow the water in the collectors and piping

to be displaced by air and drain back properly.



Drainback Configuration– What does the drainback process do?

Solar collectors and piping are empty when not operating.

Provides failsafe protection against system damage due:

– overheating in the summer, – freezing in the winter, or– electrical power outages.


Our self-interest is also the self-interest of the community & environment within which we operate.We have no choice but environmental and social responsibility. Anonymous


Drainback Configuration– Advantages

Easiest 4-season system for a do-it-yourself person to install and maintain.

Has the least maintenance of the 4-season systems.

No concerns when going away on holidays or other periods of reduced hot water requirements.

Solar collectors will last longer than in other systems.

Energy efficiency is today’s biggest global economic challenge.Office of Energy Efficiency, Natural Resources Canada


It can be stopped when the storage tank is full of hot water:– without degrading the water or causing major component failures

due to collector stagnation.

– without being concerned about boiling the storage tank or causing high system temperatures and pressures in the summer when the collectors are in stagnation mode (these would otherwise cause major system component failures).

More collectors can be added to produce more heat in the winter:– without need to dissipate excess heat in the summer when it is not

required.

Drainback Configuration– Advantages

No cathedral was ever built based on its economic return. Rob DumontStewardship always involves taking the long view. Saskatchewan Research Council


Drainback Configuration– Special Design Considerations

Installation needs to be carefully done.

Drainback needs to be certain:– all piping must be sloped,– collectors must be level, and – all water must drainback into a

warmed space.

Requires a larger pump than a glycol system due to the head pressure of the water in the piping.

Companies are motivated by the self interest Joel Nodelman,of the people who make the decisions. Sustainable Development, EPCOR


Solar Water Heating System– Installation Considerations

Plan for routing the solar collector piping from the roof to the storage tank.

Be careful about any roof and wall penetrations.

Increase in roof loading – shouldn’t be a problem, but needs to be checked.

Good southern exposure. 10% shading only causes 10% loss.


In the arena of human life the honours and rewards … fall to those who show their good qualities in action. Aristotle


Collectors – mounted horizontally on roof rack

ThermoDynamics Solar Boiler

People who are doing it…Tim Belec, Pigeon Lake


Nicely flashed into roof

People who say it cannot be done… should not interrupt those who are doing it. George Bernard Shaw


Offset from roof on a rack

If not here… If not you… If not now…then where? then who? then when?


Mounted on a metal roof

I hope we don't have to wait until oil and coal run out Thomas Edison… before we tackle solar power. (1847-1931)


Mounted against a wall


Hung over the edge of a roof


School DHW system


Array mounting – flat roof


Array mounting – rear view


Mounted on a rack above the roof line

The right to access every building in the city by private car, in an age when Lewiseveryone possesses such a vehicle, is actually the right to destroy the city. Mumford, 1981


Mounting Location

Does not have to be mounted on a house roof.

Can be mounted on garage roofs, walls, ground.

Photo Credit: Trimline Design Centre

The true voyage of discovery begins not with new places, but with new eyes. Marcel Proust


Municipal swimming pools- indoor- outdoorCafeteriasCar washesZamboni machinesSports arenasFire stationsHotels

Best suited for places that use a lot of hot water throughout the year:

66 collectors

Okotoks, indoor town swimming pool

London Ontario Raceway, horse wash

Commercial Solar Water Heating


100 flate plate collectors

Solar Heating at the Best Western Hotel –Kelowna, BC

Change only favours minds that are diligently looking and preparing for discovery. Louis Pasteur


Commercial-Sized Solar Heat Storage Tanks


Solar Domestic Water Heating


Batch water heatersThermosyphon systems

Passive Solar Domestic Water Heating

Jamaica Greece

Vancouver


Batch Solar Water Heaters

Integrated collector / storage stankMade of a black tank in an insulated, glazed box.

Cold water first passes through the batch heater. – It heats the water part of the way to the desired temperature– The water then continues to the conventional water heater for

any additional heating.

Batch water heaters are simple and reliable.

They should not be installed in severely cold climates because the outdoor pipes could freeze in the cold weather.


If you deliberately plan on being less than you are capable of being, then I warn you that you'll be unhappy for the rest of your life. Abraham Maslow


Sunwell– 3-season Solar Water Heater –

Sunwell system, Taylor Munro Energy Systems, Vancouver$200040% solar fraction (vs $6000 and 70%)Stainless steel 158 litre tank

May we begin to do good, +St. Francisfor up to now we have done very little! of Assisi


Thermosyphon system

The water flow relies on natural convection and does not requireany pump

Very simple system – no pumps, heat exchangers, controls

Not typically used in freezing climates


Questions…?




Next

For of those to whom much is given,much is required. Luke 12:48


Operating Costs…

Operating costs:– Solar PV powered pump: $0 per year– Glycol system: $10 per year in electricity– Drainback system: $15-$20 per year in electricity

Maintenance costs:– Glycol system: $20 per year for glycol?– Drainback system: $0 per year

Going to a junkyard is a sobering experience…There you can see the ultimate destination of almost everything we desire. Roger von Oech


Costs Breakdown – Solar Domestic Water Heating2 collector system Portion

– $2100 for 2 solar collectors 33%– $1500 installation, plumbing, and electrical work 23%– $1000 pumps, piping, controls 17%– $1000 solar tank and heat exchanger 17%– $ 400 fittings, collector rack, flow meter 6%

=========~$6,000 installed price (up to $8,000) + GST

– $ 500 Government of Canada subsidy (7% of 2-collector system)

– Typically: $6000 for 1 collector system installed$7000 for 2 collector system installed, $8000 for 3 collector system installed.

It is said that 'insanity is when the inner vision of reality no longer corresponds with the external world as it really is…'


Average house uses 135 GJ per year (= $1179)

Heated air for the space in the house – called space heating(typically takes 105 GJ of natural gas = $917)

Heated water for showers, dishwashers, clothes washers –called domestic water heating (DWH) (typically 30 GJ = $262)

Optional – stove, oven, clothes dryer, BBQ, fireplace

Energy Uses in the Home – Natural Gas

Municipalities hold the key to a sustainable world in their hands. They are the perfect scale for the creation of socially and ecologically sustainable role models. Dr. Karl-Henrik Robert

Solar Energy Project Development Specialists 109$0

$500

$1,000

$1,500

$2,000

$2,500

$3,000

1

Background: Our Natural Gas Consumption

0

50

100

150

200

250

300

1

High 300 GJ

Low 35 GJ

Avg 135 GJ

High$2967 per year

Avg$1527 per year

Low$654 per year

Household Consumption

per year (Edmonton)

1 GJ = 28 litres of

gasoline

Avg 30 GJ for DWH

Annual connection fee

$348

Average DHW, $262

Charges for delivered energy

DWH

DWH

Fuel Consumption Natural Gas Bill


Evacuated Tube Compared to Flat Plate

Lots of promotion of both technologiesLots of disagreements between the promoters

Efficiency: max avg January (Ti=13°C, G=300)

– FPC Enerworks residential: 72% 32%– FPC ThermoDynamics G32: 69% 30%– FPC Zen 42L: 68% 38%– ETC Thermo Tech Mazdon 30: 53% 44%– ETC Apricus AP-22: 42% 32%

Approx. costs (for the similar collector area) (check suppliers for confirmed $ numbers)

– ETC Thermo Tech Mazdon 30: $2500 for 30 tubes– ETC Apricus AP-22: $2500 for 22 tubes– FPC Zen 42L: $2100 for 6’x8.5’ collector– FPC ThermoDynamics S32: $1000 for 4’x8’ collector


0

10

20

30

40

50

60

70

80

90

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20

(Ti-Ta)/G

Col

lect

or E

ffici

ency

(%)

-- ba

sed

on N

orth

Am

eric

an R

atin

g M

etho

d

Thermo TechTMA 600-30

Thermo DynamicsG32-P

ApricusAP-22

ZenThermic 42L

EnerworksCOL-4x8-TL-SG1-SD10US

EnerworksCOL-4X8-NL-SG1-SH10US

ThermomaxSolarmax AST30

Collector Efficiency

Ti – temperature of inlet fluid to solar collector [°C]Ta – temperature of air surrounding solar collector [°C]G – solar energy on collector surface [W/m2]

Collector efficiency reduces with colder and/or cloudier weather

Cloudier and/or colderSunnier and/or hotter

Avg January day


Ultimate Collector Performance– 2 collector residential system

$0

$5

$10

$15

$20

$25

$30

$35

$40

$45

$50

$55

$60

January February March April May June July August Sept ember Oct ober November December

Thermo DynamicsG-32

ThermomaxMazdon 30 - TMA 600S

Wat er Loads Solar radiat ion

$/month

Average


Collector Performance – evacuated tube compared to flat plate

$0

$5

$10

$15

$20

$25

$30

January February March April May June July August September October November December Average

Thermo DynamicsG-32

ThermomaxMazdon 30 - TMA 600S

Water Loads

$/month

37% efficient 46% efficient


Performance of Solar DHW Systems – Rules of Thumb

~$800092%15.2 GJ

84%13.9 GJ

57%9.5 GJ

Zen 28S– flat plate collector

3.

~$600079%13 GJ

68%11.2 GJ

45%7.4 GJ

Enerworks residential– flat plate collector

1.

~$8800

~$6500

2-collector system cost

98%16.1 GJ

90%14.9 GJ

61%10.1 GJ

Thermo Tech Mazdon 30:– evacuated tube collector

4.

71%11.8 GJ

2

81%13.4 GJ

3

47%7.8 GJ

Thermodynamics G32– flat plate collector

2.

1Collector brand Qty:

Solar savings for average household (%)Annual energy production (GJ)

Costs not to be taken as definitive

Anyone who challenges the prevailing orthodoxy finds himself being silenced with surprising Georgeeffectiveness. A genuinely unfashionable opinion is almost never given a fair hearing. Orwell


Solar DWH Recovery Time

0100

500

1000

Solar Radiation Intensity[W/m2]

050%Night550%+15°C, heavy overcast

5050%Super bright

10

Recovery Rate[litres per hour]

20%

Likely System

Efficiency

-15°C, sunny day

Solar Conditions

For a typical system with 2 collectors at 3m2 per collector.With cold water temperature = 5°C, hot water temperature = 55°C.


Solar DW Water Heating Costs Solar DW Water Heating Costs –– Flat PlateFlat PlatePrices of Prices of delivereddelivered natural gas heat:natural gas heat:

–– 8 $/GJ to 32 $/G8 $/GJ to 32 $/GJ, rising at 7% per year (over the last 15 years)–– 10% to 25% subsidy10% to 25% subsidy ($1.20 to $2.30 /GJ, on residential bills)($1.20 to $2.30 /GJ, on residential bills)–– depends on efficiency of the heater, fluctuating North American depends on efficiency of the heater, fluctuating North American market market

prices, prices, government policies and subsidies, and cost of carbon emissions

Prices of Prices of delivereddelivered solar heatsolar heat:–– 20 $/GJ to 23 $/GJ with 0% interest rate20 $/GJ to 23 $/GJ with 0% interest rate

34 $/GJ with 6% interest rate34 $/GJ with 6% interest rate–– $500 rebate$500 rebate (8%) from Government of Canada

–– fixed price for 25 yearsfixed price for 25 years

Depending on solar and natural gas rebates, and snow cover:–– ROIROI: 5% to 6% per year–– Payback:Payback: 13 to 19 years depending on installation, and subsidies13 to 19 years depending on installation, and subsidies

Socialism collapsed because it did not allow the market to tell the economic truth. Øystein DahleCapitalism may collapse because it does not allow the market to tell the ecological truth. Exxon Norway


Emission Reductions

For a 2-collector system on a standard household:

– 66% reduction in water heating emissions

– 1000 kg of CO2 reduction per year (with partial snow cover)

– 1200 kg of CO2 reduction per year (with no snow cover)

Service to others…is the rent you pay for your room here on earth. Muhammad Ali


Background: Natural Gas Prices (Edmonton)

$0

$1

$2

$3

$4

$5

$6

$7

$8

$9

$10

$11

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

$/GJ2006: $10.27 /GJ

2007: $8.73 /GJ

It may seem impossible to imagine that a technologically advanced society could Elizabeth Kolbertchoose, in essence, to destroy itself, but that is what we are now in the process of doing. New Yorker

Average increase is 7.2% per year over the last 19 years


Background: Natural Gas Connection Fees

$0

$50

$100

$150

$200

$250

$300

$350

$400

$450

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

$/year

2006: $320 per year

2007: $348 per year

In many ways our future is passing us by, Gary Lamphier… and our energy riches may one day look like fool's gold. Edmonton Journal

2008: $401 per year

Average increase is 5.8% per year over the last 19 years


Amount of natural gas used (kWh)

Natural Gas bill ($)

Total connection fee ($348 per year, 23% of natural gas bill)

Actual price of natural gas including purchase, delivery, taxes and GST ($8.73 /GJ) (before subsidies)

Average natural gas consumption

Average home bill: $1527 per year

135 GJ/year0$0

Apparent price of natural gas ($11.31 /GJ)

{Commodity fee $1179

Average home natural gas bill

Connection fee + commodity feeSelling gas, delivering gas, municipal access fees, GSTCommodity fee = quantity of gas purchased and delivered + municipal access fee + GSTFor a typical house, the potential savings are $1179(77% of gas bill) unless you go completely off-grid.

Electricity price of 11.17 ¢/kWh expressed in $/GJ to compare with natural gas: $31.03/GJ

Natural Gas Bill Natural Gas Bill (Edmonton)(Edmonton)


$6.18 $6.75$8.73

$11.31

$20.56

$28.55

$0

$5

$10

$15

$20

$25

$30

Price ofpurchased fuel

- averaged

Price ofpurchased fuel

- prorated

Price ofdelivered fuel

Apparent priceof delivered fuel

Apparent priceof heat

Cost for air-emissions free

heat

Price of Natural Gas Heat

– from Perception to Reality…$/GJ

Presumed cost of natural gas: $834Presumed cost of fixed charges: $693

Including $/GJ

delivery fees

Including pro-rated $/month

connection fees

Including appliance efficiency

Including buying wind-

powered emission offsets

And what about the

cost of other

environ-mental

damages?

Read directly

from gas bill

Prorated over monthly consumption


Going off the Gas Grid…

Here is how to calculate when your heating bill will be less by using electricity than natural gas:

Threshold [GJ] = Annual gas connection fees [$/year]–––––––––––––––––––––––––––––––––––(electricity heat price – natural gas heat price) [$/GJ]

Electricity heat price [$/GJ] = electricity price [¢/kWh] /100 /3.6 *1000

Natural gas heat price [$/GJ] = natural gas fuel price [$/GJ]––––––––––––––––––––––––––––––––––

average efficiency of your home’s appliances (typically 60% for standard furnace and water heater)

For a typical house: 23 GJ = $348 / (11.17 /100 /3.6 *100 – 8.73 / 60%)= $712 annual natural gas bill= 17% of average house use now


Questions…?




Next

The future does not belong to those who are content with today, fearful in the face Robert Kennedyof new ideas and bold projects. It will belong to those with a personal commitment. 1966


Decide why you want solar in your house

– $ savings, emission savings, peer leadership…

The solar industry is contacted by many many tyre kickers…

– This is not helpful to anyone

– If you come prepared then you will show that you are serious and so get noticed and respected

Your own solar system– getting ready

In the past 30 years, 1/3 of Earth resources have been consumed. In the next 50 Worldwide Fundyears, the population will double, & natural resources will fall by 50 - 75%/person. for Nature, 1998


Size of your solar water heating system depends on:

How much water do you use in a year?– average residential hot water usage is 225 L/day (= 40% of total water use)

(you can guess how much your water heat usage is with your 3 summer bills)

If you use less water to begin with, then the size of your solar heating system is smaller! …and way less expensive

Get your natural gas and water bills together for at least 1 year(2 years is even better).Add up all the natural gas and water that you use.

– This gives equipment suppliers a good idea of how much energy you use and so what % that their system can supply you.

Becoming Solar Ready1. How much do you need?

Rules are for the obedience of fools Douglas Bader…and the guidance of wise men. WWII pilot, Britain



How much of your water heating you want to get from the sun?

How many $ per year?orWhat % of your energy? 10%, 50%, 100%, ???orHow many GJ are you wanting?

This number is a target. You don't have to have all your heating provided by solar.This is decided by knowing how much heating you are using and what is your budget – and it is a guess until you know the other figures.

Becoming Solar Ready2. How much do you want?

Economic prosperity goes hand in hand with good health and a clean environment.…These inalienable rights are also the mission of successful companies.


Becoming Solar Ready3. What is your budget?

2 solar heating collectors

4


How much do you want to spend?– a solar water heating system is generally modular

and so can be sized to fit your budget– Typically people only use 1, 2, or 3 collectors

16



How much energy is in the sunlightwhere you are located?

– 20% difference annually on a 6/12 roof between Fort McMurray and Lethbridge

– 20% difference in the winter on a vertical surface between Fort McMurray and Lethbridge

Becoming Solar Ready 4. Where do you live?

RETScreen spreadsheet analysis software available free from Natural Resources Canada

www.retscreen.net



How clear are your solar sightlines from obstructions?

– from trees (now and in the future)– from other houses or high buildings?

Shading reduces the amount of solar heat you can produce– where are your coniferous and deciduous trees?

Becoming Solar Ready5. What are your solar sightlines?


Size of your solar water heating system is affected by:

What are your roof or wall orientations?– does your roof slope north and south?– are your walls facing south– is your back yard or your front yard facing south?– are they free from obstructions? (vents, dormers)– how much area is there?

What do you do if they are not the right orientation?

Becoming Solar Ready6. What are your roof and wall orientations?

Too many obstructions

fill up the roof


Space from mechanical room to attic– "Chase" for 2 insulated solar hot water pipes

– Make sure this is sealed to prevent air and moisture from entering the attic

Space in mechanical room– Wall area:

– 2 m2 for valves, fittings and a small tank

– Floor area:– To accommodate another water tank

about the size of your present one

Becoming Solar Ready – Preparing a new home


Your own solar system– approaching designers and suppliers

Supplier– …designs and specifies the system based on your needs and desires– Does the supplier know how to design well?– How do you evaluate their prices?

Installer– …installs the system according to the design of the supplier– Does the installer know how to install well?– How do you evaluate their prices?– Plumbers can install a solar heating system– You can install it yourself???


Look at the Eco-Solar Products and Services list for suppliers

Contact 3 suppliers– Look at web sites to see what they supply. – Ask for 3 references to make sure they know what they are

speaking about.

Make sure they are members of the solar industry association:– Canadian Solar Industries Association (www.cansia.ca)

– This helps ensure that they have good relationships with their peers, and so are wanting to be in business for a long time.



Give the supplier some photos of your house, showing:– the view of the front yard from the south,

showing the general house and trees,

– the roof and walls, showing obstructions, slopes, and shapes

– the view to the south from the house, showing trees and other buildings

– the furnace room to show them an idea of how much space there is on the floor and walls available for equipment




Good suppliers know how to design and size your system, not just supply you with some parts!

– Ask lots of questions to make sure they know what they are talking about.

– Do they have a system package for you (rather than bits and pieces)?

– Do they have professional brochures of their equipment?(this shows they are serious about their products)



Good suppliers:

– Do they have a list of all the parts that are neededso you get an idea of how organised they are, so you see what may be missing and that you still need to organiseon your own?

– Do they have a relationship with qualified installers with whom they have worked before?

You don't want to go out and try and find one on your own!Suppliers don't necessarily make good installers!


Be aware when getting price quotes for systems:– Is it a firm quote or an estimate that they can change?

– Are they interested in talking with you about your energy needsor just selling you a system?

– Make sure they indicate how many GJ their system will supply!!!Calculate their system price in $ per annual GJ supplied.

– Look at product delivery times, warranties, ask about service call-back promises, how close are they to you…

– Ask them what makes them better compared to others.Don't let them put down their competitors, just ask them to make themselves look good.

Go with confidence… contact me if you have any Q.

Your own solar system– how to buy


Questions…?




Next


0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual0

100

200

300

400

500

600

700

800 Natural gas consumption [MJ/day]

Solar radiation - 27° [MJ/m2/day]at 35% efficiency

Solar radiation - vertical surface [MJ/m2/day] at35% efficiency

Gas Consumption MJ/d

Incoming Incoming Solar Solar EnergyEnergycompared to compared to

House Heating NeedsHouse Heating NeedsSolar Energy MJ/m2/d

We consume 7 times more natural gas in January than July. Daily min/max ratio is much more.

We get 1.7 times more solar energy on a vertical surface in March than in June! Daily ratio is much more!


Solar Solar Energy ValueEnergy Valuecompared to compared to

House Heating House Heating CostsCosts

$0.0

$0.5

$1.0

$1.5

$2.0

$2.5

$3.0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec$0

$50

$100

$150

$200

$250

$300

Gas purchase cost [$per month]

Solar energy's value indisplacing natural gasat 90° tilt [$ per monthfor 1 m2]

# of solar collectors needed (using monthly averages, each collector: 3m2):

47 31 29 26 18 2 1 3 10 15 35 47

These numbers are approximate and are NOT to be used for the purposes of design and sizing of a solar heating system. They are intended to be used to illustrate the importance of energy efficiency.

Gas Cost $/month

Solar Energy Displacement Value $/m2/month


Amount of energy in sunshine in Edmonton is 5.9 GJ/m2.year.Typical home in Edmonton uses

– 135 GJ of natural gas, – = approx. 105 GJ for space heating + 30 GJ for water heating.– This house would need 58 solar collectors to heat it 100% in the

winter, at an installed cost of some $120,000. At 3 m2 each, the collectors would take up a roof area of 170 m2, bigger than the house!

In contrast, an example R-2000 home might use 48 GJ for space heating + 20 GJ for water heating.

– This house would need 18 solar collectors to heat it 100% in thewinter, at an installed cost of $40,000. (54 m2 of house roof area)

Solar Space HeatingSolar Space Heatingon Standard Homeon Standard Home

These numbers are approximate and are NOT to be used for the purposes of design and sizing of a solar heating system. They are intended to be used to illustrate the importance of energy efficiency.


Solar & Energy Efficiency– How do they relate?

No energy efficiency…?Large use of heat…

less expensive solar energy

system

Then you don't need nearly as much

heat energy…

large solar energy system

large amount of heat storage

less expensive heat storage

When employing energy efficiency…


The most important thing to start with!

The cheapest energy you will ever find!!

#1. Start with an energy audit! It is a roadmap to the energy use in your home. From this map, then you can make the decisions that are important to you.

ATCO: www.atcoenergysense.com $225VerdaTech: www.energyexperts.ca $300

Heating Energy Efficiency


20%Reduction in an average household natural gas bill

4.03 $/GJ

$324/year savings

6% return on purchase

15 year cost payback

Cost of energy efficiency high efficiency gas furnace (92% efficient)Replacing a standard efficiency (62% efficient)

10.27 $/GJCost of natural gas in Edmonton (including delivery and taxes) in 2006. This is 35% of the cost of electricity.

The Cost of Energy Efficiency - Furnaces -

Natural gas energy efficiency is a secure investment.


Rob Dumont's Home, Saskatoon

"The best insulated house in the world"

Solar space heating collectors


Factor 9 Home - Regina

Solar space heating collectorswww.factor9.ca


Riverdale NetZero Energy Homeduplex1844 ft2 per side3 bedroomssouth-facing

R-56 wallsR-100 ceiling

R-24 basement floor6.6 kW at -32°C

Passive solar for space heating– all windows

Active solar heating system for water and space heating-21 m2, vertical, 17000 litre main storage

Solar PV system for electricity – 33 m2, 5.6 kW, 53°tilt


12 kW electrictop-up water heater

17,000 litrewater-filled solar heat storage

tank

Solar Pump

8w

7w

6w5w

1s

2sDrain water heat recovery unit

Household hot water loads

Solar thermal collectorsQty: 7 Brand: Conergy from BelgiumGross area: 3.1 m2 each, 21 m2 total

WaterMains

Heat exchanger4s

3s

9w

Household water heating(This shows concept.

Actual design is slightly modified.)


12 kW electrictop-up water heater

17,000 litrewater-filled solar heat storage

tank

Solar Pump

10f

6h

5h

Fan-coil

pump

Fan-coil

12a

14a

Coolreturn air

from house

Heated supply air to house

Home heating(This shows concept.

Actual design is slightly modified.)

Solar thermal collectors

1s

2s

4s

3s

7h9f

11f

13a

8h


Solar assist heat pump

(This shows concept.Actual design is

slightly modified.)

Very small, ¾ T capacity (like a large fridge)

Makes the solar collectors more efficient in winter- cools storage tank faster

Allows more heat to be drawn from the solar tank- about 600 kWh

Provides cooling in the summer, if needed


Riverdale NetZero heating

system schematic


Riverdale NetZero solar heating

system plumbing


Questions???Questions???

What haven't I covered for you?


…we hold the future in our hands

But will our children want to live in what we are giving to them?

Gordon Howell, P.Eng.Howell-Mayhew Engineering

EdmontonPhone: +1 780 484 0476E-mail: [email protected]

©1995-2008Photo credits: Gordon Howell and several others

Emerald Award 2002

Love does not dominate Johann…it cultivates. Goethe

Solar Domestic Water Heating – How to get Started · 2016-10-20 · Solar Energy Project...

Documents

Transcript of Solar Domestic Water Heating – How to get Started · 2016-10-20 · Solar Energy Project...