SOLAR WATER HEATER
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Solar Water Heater
1600 Wilson Boulevard, Suite 500
Arlington, Virginia 22209 USA
703/276-1800 . Fax: 703/243-1865
SOLAR WATER HEATER
WHAT IT IS AND HOW IT IS USEFUL
MAKING THE DECISION AND FOLLOWING THROUGH
Thermosyphon Principle at Work
Collector--Flat Galvanized Metal Sheets
Collector--Corrugated Metal Sheets
Collector Stand and Storage Platform
Tank and Collector
VII. OPERATION AND
VIII. CONVERSION TABLES
IX. DICTIONARY OF
DECISION MAKING WORKSHEET
APPENDIX II. RECORD
Solar Water Heater
I. WHAT IT IS AND HOW IT IS USEFUL
Hot water is not always necessary, and in warm climates it
be relatively easy to do without.
It is, however, more
effective than cold water for many purposes.
Even so, in some
areas hot water is not used because fuel is so expensive it
used only for essential tasks.
A solar heater can supply needed
hot water without using up available fuel.
Solar water heaters represent one of the easiest, most
practical applications of solar energy on an individual and
Heat from the sun's rays is easily captured.
surfaces exposed to the sun will get hotter than those of
other color. A metal
surface painted flat black and placed in
contact with water will heat the water.
The black metal plate
is called an absorber.
Once the water is heated, it is kept hot with
heated water behind the absorber can be insulated with a
variety of substances such as fiberglass, straw, sawdust,
or polyurethane foam.
In some absorber designs a sheet of glass
is placed between the absorber plate and the sun.
transmits the high radiation from the sun that heats the
but stops the low-energy infrared radiation that is
from the hot absorber.
It also keeps air from passing over the
absorber causing heat loss.
The reduction of the two forms of
heat loss makes glass an ideal insulator.
Clear plastics can be
used but their life expectancy is limited.
The solar water heater presented here (see Figure 1 ) can
hot water the year round.
This system will heat 70 liters (18-1/2 gallons) of water to
60 [degrees]C (140 [degrees]F) between sunrise and noon on a
clear day with an
average outside temperature of 32 [degrees]C (90
[degrees]F). Obviously, water
does not have to be this hot for many purposes:
very hot water
can be mixed with cool water to provide water warm enough
bathing and washing clothes and dishes.
This factor should be
taken into account when estimating the amount of water
Building a solar water heater can be a good project for a
* The heater, assuming access to the right equipment, is not
difficult to build.
* It provides a working demonstration of the principles of
* Students introduced to solar technology and its potential
with energy-conserving, non-polluting
II. DECISION FACTORS
* Heating water.
* Washing clothes.
* Personal hygiene.
* Easy to build and operate.
* Provides heated water 60 [degrees]C
(140 [degrees]F) within
a two-hour period.
* No fuel costs.
* Has to be filled manually.
* Life expectancy of
* Heats water only on sunny
days. Does not
operate at night.
$30-$70 (US) including materials and labor.
(*) Cost estimates serve only as a guide and will vary from
country to country.
III. MAKING THE DECISION AND FOLLOWING THROUGH
When determining whether a project is worth the time,
and expense involved, consider social, cultural, and environmental
factors as well as economic ones.
What is the purpose of
the effort? Who will benefit most? What will the
be if the effort is successful? Or, if it fails?
Having made an informed technology choice, it is important
keep good records.
It is helpful from the beginning to keep
data on needs, site selection, resource availability,
progress, labor and materials costs, test findings, etc.
The information may prove an important reference if existing
plans and methods need to be altered.
It can be helpful in pinpointing
"what went wrong."
And, of course, it is important to
share data with other people.
The technologies presented in this series have been tested
carefully, and are actually used in many parts of the world.
However, extensive and controlled field tests have not been
conducted for many of them, even some of the most common
Even though we know that these technologies work well in
situations, it is important to gather specific information
why they perform properly in one place and not in another.
Well documented models of field activities provide important
information for the development worker.
It is obviously important
for a development worker in Colombia to have the technical
design for a kiln built and used in Senegal.
But it is even
more important to have a full narrative about the kiln that
provides details on materials, labor, design changes, and so
forth. This model
can provide a useful frame of reference.
A reliable bank of such field information is now
exists to help spread the word about these and other
lessening the dependence of the developing world on
expensive and finite energy resources.
A practical record keeping format can be found in Appendix
IV. PRE-CONSTRUCTION DECISIONS
The solar water heater presented here (see Figure 2) was
designed, developed, and tested in Afghanistan in the late
1960's. Since that
time, this heater has been built and used by
development workers around the world.
There are two main parts to the solar water heater:
(1) a heat-absorbing
collector (absorber) that is rather like an envelope
made of metal sheets; and (2) a storage tank that holds the
water for the system.
The collector can be made either of flat
galvanized metal sheets or corrugated galvanized metal
Instructions are included for both types of materials.
THE THERMOSYPHON PRINCIPLE
* The tank, filled with water, is connected to the
* The collector is positioned below the bottom of the tank.
* Water runs through a hose at the bottom of the tank to the
* The water is heated in the collector.
* Hotter water flows toward the top of the collector.
* Hot water is forced out of the hose at the top of the
collector into the
tank by the pressure of the cooler
coming in from the tank.
* The hotter water stays at the top of the tank and cooler
water flows to the
collector. The flow established
until the water is
no longer being heated by the sun. For
example, at night
the flow becomes stable and the hot water
remains until it is
used or it cools.
THE THERMOSYPHON PRINCIPLE AT WORK
It is important to remember that the storage tank must be
located 46cm (18") or higher above the collector to
thermosyphon principle to work (see Figure 3).
If you cannot place this water tank above the collector, a
will be needed to move the water from the collector to the
tank, and that will increase expenses.
The quantity of water to be heated is a primary concern.
Americans use, on the average, 95 liters (25 gallons) per
per day. However, for a lifestyle which does not include a
hot shower or bath each day and an automatic clothes washer,
the quantity of water needed is much less. In many areas, 38
45-1/2 liters (10 to 12 gallons) per person per day is
In others, people often are required by circumstances to
"make do" with 7-12 liters (2-3 gallons) of water
Water, in such areas, is so precious even in very small
that whether or not it is hot is of no great importance at
all. (For these areas, a solar distillation unit might be an
important technology to introduce.)
If the water heater is needed for a small infirmary or a
school, make an estimate of the number of gallons required
each person and for each purpose. The storage tank may need
be made larger, depending upon this need. Collector size
also be considered--it directly relates to the quantity of
water desired. A good general rule is one square meter
square) of collector area for 41-1/2 liters (11 gallons) of
water desired. In colder climates, one square meter
square) of collector area may yield only 30 liters (about 8
gallons) per square meter.
Site conditions are important. Collectors should face
south. Turning a collector southeast or southwest can affect
its performance by about 20% or more. If hot water is needed
noon, face the collector to the southeast; if hot water is
important in late afternoon, face the collector to the
southwest (see Figure 4).
The site should be free from shade. Collectors should be
so that they can be tilted from the horizon to an angle
to the latitude of the location. (In more temperate climates
the angle should equal the latitude plus 10[degrees]. If the
is unknown, the collector can be placed at a 45[degrees]
in areas near the equator). The latitude for your area can
obtained from an atlas or globe.
V. CONSTRUCTION NEEDS
Materials and tools needed for a 90cm X 180cm (35-1/2"
absorber/collector and a 70-liter (18-1/2 gallon) storage
are listed below.
* Metalworking tools: hammer, anvil, soldering equipment,
* Drill and 6mm (1/4") drill bit
* Pliers or 6mm (1/4") wrench
For Flat Sheet Metal Collector
* Galvanized sheet metal: 2 pieces, 90cm X 180cm
* Galvanized sheet metal pipe: 2 pieces, 2.5cm diam. X 5cm
(1" X 2")
* Galvanized stove bolts: 28, 6mm diam. X 2.5cm long
* Metal washers: 56, to fit 6mm (1/4") bolts
* Rubber washers: 56, to fit 6mm (1/4") bolts. Inside
outside diam. 2cm (3/4"). These can be cut from
heavy truck tire
For Corrugated Metal Collector
* Corrugated metal sheet [galvanized], 122cm X 244cm
* Galvanized sheet metal pipe: 2 pieces, 1.25cm diam. X 5cm
long (1/2" X
* Galvanized stove bolts: 80, 6mm diam. X 2.5cm long
* Metal washers: 160, to fit 6mm (1/4") bolts
* Rubber washers: 400, to fit 6mm (1/4") bolts. Inside
outside diam. 2cm (3/4")--can be cut from heavy
truck tire inner
* Reducer connections: two, to connect 1.25cm (1/2")
Note: Nuts, bolts,
washers quantity will vary. Some sheets
corrugations spaced more closely than others. A
with very closely spaced corrugations will
fasteners. The figures given here for the
metal collector are approximate amounts.
For Either Kind of Metal Sheet
* Rubber hose: 2 pieces, 2.5cm (1") diam. [long enough
collector to tank]
* Galvanized sheet metal tank:(*) 70-liter (18-1/2 gallon)
faucet, removable lid, and 2.5cm (1") hose
placed two-thirds from the bottom and one
placed at the
* Paint: 1 liter (approximately 1 quart), flat black or
homemade mixture of
linseed oil and carbon black (charcoal
* Quantity of mud bricks, straw or other suitable material
absorber and storage tank)
(*) The best tanks are glass-lined steel tanks or
insulated water heater tanks. Obviously, these are
in many areas. One suitable alternative is a 113.5-liter
drum; it must be painted with rustproof paint or lined
with plastic. Another alternative is to have a blacksmith
a tank for the project. In most areas, the local
shop would be able to put together such a tank quickly. Be
it is watertight.
THE COLLECTOR--FLAT GALVANIZED METAL SHEETS
* Cut 2cm (3/4") off the length and width of one of the
steel, so that it will be 1cm (1/3") smaller
than the other
sheet on all four sides (see Figure 5).
* On the smaller sheet, drill two 3cm (1-1/4") holes
Drill 4cm (1-1/2") in from the edges (see
* Place the two galvanized sheets together. Using a hammer
anvil, fold the 1cm
(3/8") overlapping edges (see Figure 6).
* Fold the edges 1cm (3/8") again and solder them to
airtight seal (see
* Drill holes for 6mm (1/4") bolts at regular
buttons on a
mattress (see Figure 8). Bolts will keep the
sheets from being
forced apart when the absorber is filled
* Place bolts in holes with rubber and metal washers at each
end of the bolts to
ensure a watertight seal (see Figures 9 and 10)
* Use the 2.5cm X 5cm (1" X 2") galvanized sheet
metal pipe to
connectors. Place the pipe flush with the solar
covering the 3cm (1-1/4") hole. Solder the
pipe to the sheet
(see Figure 11).
* Paint the front of the heater with black paint so that it
will absorb the
sunlight rather than reflect it.
THE COLLECTOR--CORRUGATED METAL SHEETS
* Take two corrugated sheets 122cm X 244cm (48" X
96") and cut
off the width of both sheets and 64cm (25")
off the length of
both sheets. Save the scrap metal.
* Place the two sheets together and drill 6mm (1/4")
apart in alternate corrugations (raised sections),
see Figure 12.
* Place 6mm X 2.5cm (1/4" X 1") bolts in holes
washer and rubber
washer. Separate the two sheets. Place
three or four
rubber washers on bottom of each bolt so that
approximately 6mm (1/4") space between the two
sheets (see Figure
* Attach bolts on undersides of bottom corrugated sheet with
metal washer, and 6mm (1/4") nut. Tighten
until rubber washer
begins to spread.
* Cut scrap corrugated sheet into strips to fit corrugations
each edge of the
collector. Bend outside edges over as shown
in Figure 14. This
should seal the entire edge when complete.
A hammer and anvil
can be used to form the strips so
they will fit the
* Drill 6mm (1/4") holes 2.5cm (1") apart along
edges and at every
other corrugation on side edges.
* Fasten edges together with 6mm X 2.5cm (1/4" X
metal washer, and
* Install water inlet pipe (1.25cm X 5cm [1/2" X
2"l) in bottom
* Install water outlet pipe (1.25cm X 5cm [1/2" X
2"]) in top
* Solder all outside edges including bolt holes. Solder
inlet and outlet
* Attach reducer connections to the inlet and outlet
* Paint front side of collector flat black to absorb
MAKE THE STORAGE TANK
A 114-liter (30-gallon) drum can be used for the storage
or a 70-liter (19-gallon) tank can be made from galvanized
sheet metal. If using an oil drum, make sure that one end
be lifted off to serve as a lid. Also, be certain the drum
* Paint the inside with waterproof paint, or line with
plastic. One large
piece of plastic draped over the top edge
of the tank will
* Insulate outside by covering with mud, a mixture of tar
straw or sawdust,
* Drill holes for inlet and outlet connectors and solder
Holes should be located, for best results,
bottom of the tank
(inlet to the collector) and about two-thirds
up the side of the
tank from the bottom (outlet from
the collector to
the tank). If possible, tank should be
with a faucet on
the bottom, opposite the cold water
MAKE THE COLLECTOR STAND AND STORAGE PLATFORM
* Place so that the face of the collector faces south and is
* Build a fixed stand.
A simple way to raise the absorber is to
build up the back
and the sloping sides with mud brick.
up the back with
small boards while the bricks are being
Once the bricks are laid, remove the boards
any openings or
holes with mud. This will form a dead
space which will
serve as insulation.
* Or build a portable stand.
(A portable stand is usually
cheaper and is
easily moved to track the sun.) Substitute a
wooden frame for
the mud brick platform. Put insulating
material such as
straw or hair directly behind the absorber
as shown in Figure
CONNECT TANK AND COLLECTOR
* Attach a section of hose to the lower outlet (cold water)
the tank and attach
it to the lower right (cold water) inlet
on the collector.
* Attach the other section of hose to the upper inlet (hot
water) on the tank
and attach it to the upper left (hot
water) outlet on
Note: If using
corrugated sheets, make the inside dimensions
of the frame
90 cm X 180cm.
Figure 16A and Figure 16B are two possible solar
Note: Both systems
are placed so that the tops of the collectors
(18") below the bottom of the storage
VII. OPERATION AND MAINTENANCE
* Remember to keep the collector at a 45[degrees] angle if
of your area is
unknown. Latitude plus 100 in temperate
* The hot water will rise to the top of the tank.
When all of
the water is to be
used, it can be drained from the faucet;
when only a small
amount of water is needed, the hottest
water can be taken
from the top of the tank.
* Whenever water is being heated, the water level should be
kept above the
tank's upper hose connector to allow the water
to circulate or the
thermosyphon system will not work.
* The water heater works best when the connecting hoses are
short as possible.
This solar water system is virtually maintenance free.
hoses may have to be replaced every two or three years.
metal other than galvanized sheet metal is used, such as
untreated sheet metal, the lifespan of the system will be
shortened considerably due to rust.
Once the collector starts
to rust, it must be replaced.
Untreated sheet metal can be painted with several coats of
rustproof paint if it can be obtained.
However, you should
check the painted area in six months to make sure it is not
peeling off. It is
also helpful to wrap the tank in insulation
If a 113-liter (30-gallon) drum is used, and lined with
the plastic liner will have to be checked regularly and
may have to be replaced from time to time depending on the
mineral content of the water supply.
To begin using the solar water heater, make certain the tank
46cm above the top of the collector.
Fill the tank with clean
water. Check for
VIII. CONVERSION TABLES
UNITS OF LENGTH
= 1760 Yards
= 5280 Feet
= 1000 Meters
= 0.6214 Mile
= 1.607 Kilometers
= 0.3048 Meter
= 3.2808 Feet
= 39.37 Inches
= 2.54 Centimeters
= 0.3937 Inches
UNITS OF AREA
1 Square Mile
= 640 Acres
= 2.5899 Square Kilometers
Kilometer = 1,000,000 Square
Meters = 0.3861 Square Mile
= 43,560 Square Feet
1 Square Foot
= 144 Square Inches
= 0.0929 Square Meter
1 Square Inch
= 6.452 Square Centimeters
1 Square Meter
= 10.764 Square Feet
Centimeter = 0.155 Square Inch
UNITS OF VOLUME
1.0 Cubic Foot
= 1728 Cubic Inches
= 7.48 US Gallons
= 1.2 US Gallons
Meter = 35.314 Cubic Feet
= 264.2 US Gallons
= 1000 Cubic Centimeters
= 0.2642 US Gallons
UNITS OF WEIGHT
Ton = 1000 Kilograms
= 2204.6 Pounds
= 1000 Grams
= 2.2046 Pounds
1.0 Short Ton
= 2000 Pounds
UNITS OF PRESSURE
1.0 Pound per
square inch = 144 Pound per
1.0 Pound per
square inch = 27.7 Inches
1.0 Pound per
square inch = 2.31 Feet of
1.0 Pound per
square inch = 2.042 Inches
14.7 Pounds per square inch (PSI)
33.95 Feet of water(*)
1.0 Foot of water
= 0.433 PSI = 62.355 Pounds per
1.0 Kilogram per
square centimeter = 14.223 Pounds
per square inch
1.0 Pound per
square inch = 0.0703
Kilogram per square
UNITS OF POWER
(English) = 746 Watt 0.746
(English) = 550 Foot
pounds per second
(English) = 33,000 Foot
pounds per minute
1.0 Kilowatt (KW)
= 1000 Watt = 1.34 Horsepower
(English) = 1.0139 Metric
horsepower = 75 Meter X
horsepower = 0.736
Kilowatt = 736 Watt
(*) At 62 degrees Fahrenheit (16.6 degrees Celsius).
IX. DICTIONARY OF TERMS
AIRTIGHT--Having no place for air to enter.
ANVIL--A heavy block of iron or steel with a smooth, flat
metals are shaped by hammering.
CORRUGATED--Shaped into folds that have alternating ridges.
straight line passing through the center of a
meeting the circumference of the circle at
DISTILLATION--A process used to purify saltwater by
from the salt. The saltwater is boiled
steams. The steam condenses in a
cool receiver, and
EQUATOR--A great circle dividing the northern parts of the
earth from the southern parts of the
FIBERGLASS--A composite material consisting of glass fibers
GALVANIZED STEEL--Steel that has been coated with zinc to
HORIZON--The line or circle that forms the apparent boundary
earth and sky.
HYGIENE--THE science of preserving health; the prevention of
INFRARED--Electromagnetic radiation having wavelengths
visible light and shorter than microwaves.
INTERVALS--The space between points, things, times, etc.
LATITUDE--The angular distance north or south of the
degrees along a meridian.
LIFESPAN--The longest period over which the life of any plant,
machine may extend. How long something
POLYURETHANE FOAM--A foam made of a thermoplastic or
RADIATION--The process by which energy is given off by one
through space, water, or something
is absorbed by another body.
RUST--The red or orange coating that forms on the surface of
exposed to air and moisture.
SOLDER--A fusible alloy that joins metal objects without
them to the
melting point. The solder is applied
in a melted
STATIONARY--Permanent, not moveable.
STOVE BOLT--A small bolt, similar to a machine screw but
TEMPERATE ZONE--An area of the earth that is warm in the
cold in the
winter, and moderate in the spring
THERMOSYPHON--Moving liquid from one place to another by
TILTED--Leaning, sloping, or slanted; raised at one end.
WATERPROOF--Made or treated with a rubber, plastic, or
agent to prevent water from entering.
X. FURTHER INFORMATION RESOURCES
Bolwell, A.J. Polyurethane Foam Insulated Solar Hot Water
Brace Research Institute. How to Build a Solar Water Heater,
Leaflet L-4, 1965,
revised 1973. Brace Research Institute,
of McGill University, Ste. Anne de
Canada. Very useful, highly detailed plans
for building a
low-cost, thermosyphon water heater which uses
almost everywhere, even in developing
design has been successfully built and used
Barbados. Highly recommended.
Brooks, F.A. Use of Solar Energy for Heating Water.
Brown, R.J. "Domestic and Commercial Solar Water
Areas." Sun at Work, 4th quarter, 1966. I.S.W.
Hart & Co., P.
Ltd., Fremantle, Australia.
CSIRO. Solar Water Heaters, Circular #2, 1964. CSIRO, PO Box
Victoria, Melbourne, Australia 3190. Good basic
overview of the
theory, design, construction, and economics
of home solar water
heating systems. Contains useful
information on the
different factors to be considered at
latitudes. Quite practical; it gives one a good
idea of how a
system can be expected to perform.
Czarnecki, J.T. Performance of Exp. Solar Water Heaters in
PO Box 26, Highett, Victoria, Melbourne,
Contains detailed test results of combination
water heating systems in six Australian
cities. Has useful
mathematical formulas and graphs, for the
amount of absorber
area needed to collect a given amount of
Farber, Erich A. Solar Water Heating. University of Florida,
Fun & Frolic, Inc. "Water Heating." Solar
Energy Primer. Fun &
Frolic, Inc., PO
Box 277, Madison Heights, Michigan 48071
Khanna, M.L. Development of Solar Water Heaters in India.
Laboratory, Pusa, New Delhi, India.
Mathur, K.N., Khanna, M.L., Davey, T.N. and Suri, S.P.
Solar Water Heater.
National Physical Laboratory, Pusa, New
Miromit Sun Heaters, Ltd. Miromit Newsletter, No. 7, July
Heaters, Ltd., 323 Hayarkon Street, Tel-Aviv,
Israel (POB 6004).
Mother Earth News. "Kenneth Whetzel's Solar
of Homemade Power.
Mother Earth News, Box 70, Hendersonville,
28739 USA. An extended anecdote about building
and using a simple
thermosyphon solar water heating system
parts"--sheet metal, copper tubing, plastic, and
small metal tank
insulated with styrofoam. Of limited value.
Ridenour, Steven M. "Homemade Solar Water
Your Own Power.
Rodale Press, Emmaus, Pennsylvania USA. A
good overview of
different types of simple collectors, their
use. Includes designs of thermosyphon,
heat transfer systems. Written in simple
language, it also
presents the basic principles of solar
Running Press. Solar Energy--Some Basics, Energy Book #1.
Running Press, 38
South 19th Street, Philadelphia,
Singh, Prof. Deep Narayan. Standardized Typical Designs of
Solar Water Heater
Systems for Supplying Hot Water for
Domestic Purposes for Detached Houses in India.
Bihar College of
Engineering, University of Patna, Patna
University of Florida. Solar Energy Studies, Tech. Progress
Report #9, Vol.
XIV, No. 2. University of Florida, Gainesville,
Although rather dated, this booklet
contains a good
overview of different solar water heaters and
some information on
the principles of solar heating, as well
as a section on
"presently used" (1960) solar water heating
has a section on solar-powered
DECISION MAKING WORKSHEET
If you are using this as a guideline for using the Solar
Heater in a development effort, collect as much information
possible and if you need assistance with the project, write
VITA. A report on your experiences and the uses of this
will help VITA both improve the book and aid other similar
Volunteers in Technical Assistance
North Lynn Street, Suite 200
Arlington, Virginia 22209 USA
CURRENT USE AND AVAILABILITY
* Note current domestic and agricultural practices which
have potential for
* Document days of sunshine, seasonal changes, haze, cloud
cover. Another way
of finding the information is to search
out annual rainfall
figures and work from there.
* Have solar technologies been introduced previously? If so,
with what results?
* Have solar technologies been introduced in nearby areas?
so, with what
* Are there other current practices which might be enhanced
improved use of
solar energy--for example, salt production?
IDENTIFY APPROPRIATENESS OF THIS TECHNOLOGY
* Is there a choice to be made between a solar technology
energy technology? Or, is it important to
do both on a
* Under what conditions would it be useful to introduce a
* If solar units are feasible for local manufacture, would
be used? Assuming
no "funding," could local people afford
them? Are there
ways to make the solar technologies "pay for
* Could this technology provide a basis for a small business
NEEDS AND RESOURCES
* What are the characteristics of the problem? How is the
Who sees it as a problem?
* Has any local person, particularly someone in a position
expressed the need or showed interest in solar
technology? If so,
can someone be found to help the
introduction process? Are there local officials
who could be involved
and tapped as resources?
* How will you get the community involved with the decision
which technology is
appropriate for them.
* Based on descriptions of current practices and upon this
information, identify needs which solar technologies
appear able to
* Are materials and tools available locally for construction
* Are there other projects already underway to which a solar
component might be
added so that the ongoing project acts as
a technical and
even financial resource for the new effort?
For example, if
there is a post harvest grain loss project
improved solar drying techniques be introduced
in conjunction with
the other effort?
* What kinds of skills are available locally to assist with
maintenance? How much skill is necessary for
maintenance? Do you need to train people?
Can you meet the
* Some aspects of
this project require someone with experience
and/or welding. Estimated labor time
8 hours skilled labor
8 hours unskilled labor
* Do a cost estimate of the labor, parts, and materials
* How will the project be funded? Would the technology
Are local funding sources available to sponsor
* How much time do you have for the project? Are you aware
planting or harvesting seasons which may affect
* How will you arrange to spread knowledge and use of the
* How was the final decision reached, either to go ahead or
to go ahead, with
RECORD KEEPING WORKSHEET
Photographs of the construction process, as well as the
result, are helpful. They add interest and detail that
might be overlooked in the narrative.
A report on the construction process should include very
information. This kind of detail can often be monitored
most easily in charts (such as the one below). (see report
Some other things to record include:
* Specification of materials used in construction.
* Adaptations or changes made in design to fit local
* Equipment costs.
* Time spent in construction--include volunteer time as well
paid labor, full-
* Problems--labor shortage, work stoppage, training
Keep log of operations for at least the first six weeks,
periodically for several days every few months. This log
vary with the technology, but should include full
outputs, duration of operation, training of operators, etc.
Include special problems that may come up--a damper that
close, gear that won't catch, procedures that don't seem to
make sense to workers, etc.
Maintenance records enable keeping track of where breakdowns
occur most frequently and may suggest areas for improvement
strengthening weakness in the design. Furthermore, these
records will give a good idea of how well the project is
working out by accurately recording how much of the time it
working and how often it breaks down. Routine maintenance
records should be kept for a minimum of six months to one
after the project goes into operation. (see report 2)
This category includes damage caused by weather, natural
disasters, vandalism, etc. Pattern the records after the
routine maintenance records. Describe for each separate
* Cause and extent of damage.
* Labor costs of repair (like maintenance account).
* Material costs of repair (like maintenance account) .
* Measures taken to prevent recurrence.
MANUALS IN THE ENERGY SERIES
This book is one of a series of manuals on renewable energy
technologies. It is primarily intended for use by people in
international development projects. However, the
techniques and ideas presented here are useful to anyone
seeking to become more energy self-sufficient. The titles in
the series are:
Helical Sail Windmill
Making Charcoal: The Retort Method
Overshot Water-Wheel: Design
and Construction Manual
Small Michell (Banki) Turbine:
A Construction Manual
Solar Water Heater
Three Cubic Meter Bio-Gas Plant:
A Construction Manual
For a free catalogue of these and other VITA publications,
P. 0. Box 12028
Virginia 22209 USA
Volunteers in Technical Assistance (VITA) is a private,
international development organization.
available to individuals and groups in developing countries
variety of information and technical resources aimed at
self sufficiency--needs assessment and program development
support; by-mail and on-site consulting services;
information systems training; and management of long-term
field projects. VITA
promotes the application of simple,
inexpensive technologies to solve problems and create
in developing countries.
VITA places special emphasis on the areas of agriculture and
food processing, renewable energy applications, water supply
and sanitation, housing and construction, and small business
activities are facilitated by the active
involvement of VITA Volunteer technical experts from around
the world and by its documentation center containing
technical material of interest to people in developing
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