Can You Build a Homemade
Solar Water Heater?
Jason Franco
Mr. Kennedy
Period 2
Ruben Dario Middle Community School
Grade 8
1
TABLE OF CONTENTS
PAGE
INRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
BAKROUND INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
MATERIALS AND PROCEDURES. . . . . . . . . . . . . . . . . . . . . . . . 6
RESULTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9
DISCUSSION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
CONCLUSION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
ACKNOWLEDGEMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2
INTRODUCTION
Can you build a homemade solar water heater? I chose this topic because I was curious to
know how solar energy could be used to warm up water. It all started by a couple of simple
observation. I was taking a drive down the street with my parents when I saw a couple of solar
panels on the top of a house. I like to use a lot of hot water and it uses a lot of electricity.
Electricity costs money and we don’t have to pay for solar energy. So I wondered, is there any
way that I could build a solar water heater at my house?
I know how much hot water is used in an everyday life and how much money is spent to pay
for it. I want that money to be in our pockets and not with the electric company. In this
experiment, I would try to build a mini solar water heater right here at my house. Based on the
research I’ve made, my hypothesis is the hotter and sunnier the day is, then more the water
would heat up.
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BACKROUND INFORMATION
Most of today solar technology has been developed within the last one hundred years, but we
have used solar energy for many centuries. Around the time of 100 A.D., humans have used the
energy that comes from the sun for many purposes. One of those purposes is to heat up homes. A
Swiss scientist names Horace de Saussure is the inventor who got credit for the solar hot box or
first solar collector ever made in 1767. In 1861, A French scientist named Augustin Mouchot
received a patent for a solar engine he invented. In that time period, pretty much the only things
that solar energy were used for was for cooking food and distilled water, pumping water, and
anything in between.
In the 1880s, an American engineer named John Ericsson opened the solar energy industry in
the United States of America. He developed many solar engines used on land into steam powered
generators for ships. But at that time the person who was considered “The Father of Solar
Energy” was Clarence Kemp. He was the one who revived a patent for the firstsolar water heater.
His invention was selling in California. Later, in 1897, it became very popular and heated water
for 30 percent of Pasadena’s (a city in California) houses.
In 1908, William J. Bailey from the Carnegie Steel Company invented the solar collectors
that many Americans use today. By the end of World War I, over four thousand roof top solar
water heaters had been sold, and over sixty thousand were ordered by 1941. By the 1940’s, solar
homes became so popular that an enormous amount of housing developments were built with
active and passive solar application across the United States of America.
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In 1554, researchers of Bell Telephone discovered the sensitivity of silicon wafer to sunlight.
There the solar cell was developed. Starting from the 1950’s, photovoltaic cells (solar cells) were
used to operate and power space satellites in the United States of America. They continued to be
used as the prime power sources for space projects today. Commercial applications of
technology continue to be used and developed today from photovoltaic cells.
The oil embargoes if 1973 and 1979 and the accompanying severe increase the petroleum’s
price. The effect of this is that there would be more developments and a great demand for
renewable resource such as solar technologies. President Jimmy Carter reduced United States
dependence on foreign oil and installed solar panels on the white house and increased the
demand for solar panels. By the 1980’s, the United States solar industry had grown to have over
100 national solar companies that produce solar water heaters, solar thermal-electric, and
photovoltaic equipment. The DOE and NREL, as well as federal initiatives, are including
investment tax credit on solar technology. The cost of solar electricity has gone from twenty five
cents to 8 cents per kilowatt-hour.
Most solar panels are made out of metal or such like materials. Metal absorbs heat and is
weather proof. The color black absorbs heat better than other colors because it does not reflect.
The less an object reflects the more solar energy is absorbed which is converted into thermal
energy.
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MATERIAL AND PROCEDURES
Materials:
10” (25 cm) square piece of metal sheet

Knife or box cutter
(thin as possible)

Tubing bender

20” (51 cm) square piece metal sheet

1 or 2 pound coffee can with plastic lid or

Flat black spray paint

Lots of insulating material

Thermometer

42” (105 cm) of soft copper tubing with

Cardboard box
a diameter of 1/2”

Soldering iron and acid-flux solder
16” (40 cm) square sheet of 3 or 4 ml of

4 - Hose Repair Clamp of 3/8-7/8”
clear plastic

1” Zinc-Plated Corner Braces (20-Pack)


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a something similar

Silver Spray Paint

5/8 in. x 10 ft. of Clear PVC Tubing

A drill with a 1/2” cobalt drill bit

Tubing cutter

12” (30 cm) square of cardboard

Masking tape

Slotted screwdriver
with screws
Procedures:
1) Cut the copper tubing into 39” (98 cm) using the tubing cutter.
2) Bend the copper tubing into an S shape using the tubing bender (Once bent, the length at
the top and bottom should be 11” (28 cm), and the length at the middle should be 9” (23
cm). The tubing width should be 8” (19 cm). The tubing should be 3” (8 cm) apart from
each other.)
3) Lay and center the copper tubing onto the 10”(25 cm) square metal sheet and solder in
place.
4) Spray the plate and the copper tubing with the flat-black paint.
5) Draw a straight line 10” from each edge
6) Cut the metal sheet along the lines you did. Cut ONLY from the edge until where the
lines intersect
7) Fold the metal sheet into a form of a box.
8) Drill 2 slots on opposite sides. Each 1” from the edge.
9) Put the insulation at the bottom of the box.
10) Slide the copper tubing and metal sheet into the two slots.
11) Get 4 Zinc-Plated Corner Braces and screw each one on each corner.
12) Spray paint the collector flat black.
13) Place the piece of clear plastic on the top, fold and then tape it down to make it tight.
14) Drill one hole on the opposite sides of the can. One hole must be 1” from the top and the
other hole must be 1” from the bottom.
15) Cut the left over copper tubing in half.
16) Insert the copper tubing into the hole and solder in place. The joints must be watertight.
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17) Put1” thick of insulationat the bottom of the cardboard box.
18) Cut two holes on the cardboard on the opposite sides. One hole would be 2” from the
bottom and the other would be where you will slide the other side of the copper tubing of
the can.
19) Slide the can inside the box.
20) Put insulation around the can.
21) Cut a circle on the piece of 12” square cardboard the same size as the can.
22) Cut the cardboard into the length and width of the box.
23) Tape the piece of piece of cardboard at the top of the box.
24) Close the can with the lid.
25) Spray paint the receiver silver.
26) Cut the clear PVC tubing into two pieces. One slightly larger than the other.
27) Insert two hose repair clamp on eachclear PVC tubing
28) Connect the clear PVC tubing.
29) Tight the hose repair clamp using the slotted screwdriver.
30) Open the can and place water in it.
31) Close the can.
32) Collect data.
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RESULTS
Time
Water
Outdoor
Time
Water
Outdoor
Started Temperature Temperature Ended Temperature Temperature
Date
Weather
10/8/11
9:00
68°F
73°F
10:12
71°F
75°F
10/9/11
Scattered
Showers
Partly Cloudy
9:00
68°F
78°F
14:30
75°F
83°F
10/15/11
Partly Cloudy
7:00
68°F
78°F
13:00
75°F
82°F
Showers and
Thunderstorms
10/22/11
Sunny
N/A
N/A
N/A
N/A
N/A
N/A
10:00
68°F
70°F
15:00
75°F
81°F
10/23/11
Sunny
10:30
68°F
73°F
14:45
76°F
82°F
10/28/11
Partly Cloudy
11:00
68°F
76°F
14:00
77°F
85°F
10/29/11
9:00
68°F
76°F
14:33
80°F
86°F
10/30/11
Scattered
Showers
Cloudy
12:00
68°F
74°F
15:00
72°F
79°F
11/5/11
Partly Cloudy
6:30
68°F
62°F
12:31
69°F
72°F
11/6/11
Scattered
Showers
9:45
68°F
74°F
11:37
71°F
78°F
10/16/11
The temperature of the water is always 68°F when it is placed in the receiver. The temperature of
the water depends on the amount of sun the collector receives and the temperature surrounding it.
When it starts raining the solar water heater could not be used. First, there is no sun and second,
the receiver would get damaged since it is made out of cardboard. In the hottest day, October 29,
2011, the solar water heater received sun most of the time and the water’s temperature reached
80°F. On the coldest day, November 5, 2011, the water’s temperature increased only by one
degree.
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10
DISCUSSION
The weather and temperature of the solar water heater’s surrounding effects the water
temperature. The hotter and sunnier it is, the more solar energy is converted into thermal energy,
meaning the water would heat up more. If it is raining, I cannot place the water heater in the sun
because there is no sun and the solar water heater is not water proof. On a rainy day, the water
will not heat up.
The hottest day was day 8. The weather was pretty much sunny. Like around 14:00, it started
to get dark. I had to bring everything inside at 14:33 because it started raining. I had to bring in
the solar water heater as soon as possible before it would get damaged. As I mentioned before,
the solar water heater is not water proof. The water’s temperature was 80°F.
The coldest day was day 10. The weather was cloudy but it was pretty cold. When I placed the
solar water heater outside, the temperature was 62°F. It started raining at 12:31 and I had to bring
in the solar water heater. The temperature at the time was 72°F. The water only heated up to
69°F. The solar water heater cannot be used during the winter. The temperature in order for the
water to heat up accordingly must be 70°F or higher.
On day 4, the solar water heater was not used at all. It was raining the whole day. The solar
water heater is not water proof. This means that it cannot be used on rainy days. The
temperature of the water was 68°F and stayed at 68°F. The water did not receive any heat at all.
The solar water heater can only be used on a cloudy and sunny day.
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The temperature of the water relates with the temperature and weather around it. The sunnier
and hotter it was the more the water would heat. In order for the solar water heater to work, the
temperature must be greater than the water’s temperature and the weather must be either cloudy
or sunny. On 3 of the days that I tested my solar water heater, I had to bring in the solar water
heater in because it started raining. This machine is recommended to be used on a hot summer
day. It is not recommended to be used on a cold and/or rainy day. The solar water heater could
be used on a cloudy day but it will not be as effective as a sunny day.
Days 2, 3, 5, 6, 7, and 8 were the days that the water heated up the most. The highest
temperatures of those days were all above 80°F. The coldest days were days 1, 4, 9, 10, and 11.
On these days it either rained, or was cloudy. Also, the temperatures for those days were less
than 80°F. The solar water heater work best on temperature higher than 80°F.
The water’s temperature all depends on the weather and temperature surrounding the solar
water heater. The sunnier and hotter the day was, the hotter the water got. When conducting the
experiment I always placed the same temperature of water and placed the solar water heater at
the same location each day. Also, I placed the same amount of water in the solar water heater for
each day. On rainy days, the solar water heater was not placed outside to prevent damages of the
solar water heater.
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CONCLUSION
I have built my solar water heater and completed my experiments. The temperature of the
water pretty much depended on the temperature and weather around it. The hotter and sunnier
the day the hotter the water was. On rainy day the solar water heater could not be placed outside
because it was not water proof. On the coldest days, the water only heated up to 69°F. The solar
water heater should be used on sunny and hot days. It is not recommended for cold days.
Based on the research I made, the materials I’ve used had to receive lots of sun to warm up.
So, I created a hypothesis stating the hotter and sunnier the day, the hotter the water would be.
Based on the data I collected, it proves that my hypothesis is correct.
If I wish to reattempt this experiment later on in the future, I would improve my solar water
heater and make it water proof.
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ACKNOWLEDGEMENTS
I would like to acknowledge the assistance of the following persons:
Mr. Kennedy, my science teacher, for reviewing the parts of the scientific method and guiding
me through some of the research.
Efrain Franco, my father, for purchasing the materials for the experiment and helping me with
some parts of building the solar water heater.
Gelacio Gonzalez, my grandfather, for soldering the plate and copper tubing together, and
guiding me throughout the whole experiment.
Ms. DiVittorio, media specialist, for helping me with my problem statement, and hypothesis.
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BIBLIOGRAPHY
Mahaney, Ian F. "Solar Energy." Solar Energy. New York: PowerKids, 2007. Print.
Rhodes, Christopher J. "Solar Energy: Principles and Possibilities." Science Progress 22 Mar.
2010. Print.
Rickard, Graham. Solar Energy. Milwaukee: G. Stevens Children's, 1991. Print.
"Solar Energy HISTORY -- Learn Who Discovered SOLAR ENERGY." Solar Energy
Advantages Disadvantages and Solar Power Information. Small Biz Web Solution, 2005-2006.
Web. 14 Oct. 2011. <http://facts-about-solar-energy.com/solar-energy-history.html>.
"Solar Energy Research Information." Science Fair Project Topics in Solar Energy. Web. 12
Oct. 2011. <http://www.makeitsolar.com/solar-energy-information/>.
"The History of Solar Energy." U.S Department of Energy. Web. 12 Oct. 2011.
<http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf>.
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