To begin with we have collected empty cans from which we will assemble solar panels. It is necessary to wash the cans immediately, because they very quickly begin to spread odors. Attention! Cans are generally made of aluminum, but there are some iron. You can test cans with magnet.

We have marked three holes on each can with nail, then drilled the bottom using the tools shown in Picture 2 and 3.
It is necessary to note that as precisely cut and form a small fin at the top of the can. Their task is to encourage turbulent flow of air within each solar tube so that air passing through the pipe, collect more heat from the heated wall of cans. So, carefully cut the top of the cans in the form of star, and then distort free parts using pliers (Picture 1). All this is necessary to do before gluing cans.

Picture 1	Picture 2	Picture 3

WARNING! This procedure is extremely dangerous because the can walls are very thin.
Sharp parts may cause injury on hands.

When the drilling is completed, small parts of the metal could remain in the can. It is recommended to use pliers to remove these parts.

Do not remove pieces of sheet metal, chips and debris with bare hands!

Remove grease and dirt from the surface of cans. Any synthetic degreasing agent will serve quite well for this purpose. Do this only outdoors or in well-ventilated room.

WARNING! This procedure is flammable and a potential risk of explosion!
It is dangerous to do this near open flame or cigarette!!!

Glue all cans using any adhesive silicone resistant to high temperatures, at least up to 200 ° C. There are products for bonding that can withstand up to 280 ° C or 300 ° C. Top and the bottom of cans are compatible and fit perfectly to each other. Put glue/silicone on the edge of can and press other can on it. In this way the glue/silicone will not run away from the edge. Detail of the soldering tin, you can see in Picture 4, and series of taped and finished cans are shown in Picture 5.

Picture 4	Picture 5	Picture 6

Prepare a template for stacking cans – shown in Figure 6. You can use the two most ordinary flat boards and connect them with nails. Template will provide support during the drying cans to get a straight pipe – solar tunnel. In addition, attach the cans for a template using the rubber for jars.

Picture 7	Picture 8	Picture 9

Pictures 7, 8 and 9 show the process of gluing. A series of glued cans form a solar tube. Picture 10 shows the pipe that must be fixed and motionless until the glue is completely dry.

Picture 10

Boxes of intake and exhaust parts are made of wood or aluminum, 1 mm (Figures 11 and 12), gaps around the edges are filled with adhesive tape or heat-resistant silicone. The box are drilled, cut-outs are 55mm in diameter. Drilled parts can be seen in Figures 12 and 13 The first row of cans is glued to the cover of the suction boxes, see how it looks when all parts are assembled and prepared for painting (Figure 13).

The adhesive dries very slowly. It is necessary to leave it at least 24 hours.

Picture 11	Picture 12	Picture 13

Solar absorber fit in the casing made of wood (Fig. 14). Back of the box solar collector is made of the plywood. In order to further consolidate the structure, you can make the inner wall of the strip. Isolation between partitions set – rock wool or styrodur insulation. Cover all this with a thin plywood panel. Installed insulation can be seen in Figure 15. Pay special attention to the insulation around the opening for the exit and entrance of air in the solar collector.

Picture 14	Picture 15	Picture 16	Picture 17

Preparation, protection and paint of timber from which the box is assembled is finished. Hooks are attached to all four corners of the solar collector, so it can be mounted on the wall (Fig. 16) using 10 mm screws (Fig. 17). An empty box is placed on the wall in order to precisely determine the place and mark the spot of drilling the inlet/exhaust.

Picture 18	Picture 19	Picture 20

At the end, the solar absorber is painted in black and placed in the case. The casing is covered with plexiglass that we attach to the frame and thoroughly complained silicone. Polycarbonate / plexiglass is slightly convex in order to gain greater strength. You can see installed solar absorber without plexiglass in picture 18. Complete solar collector is shown on Picture 19, and finally, installed solar system can be seen in Picture 20.

Click here if you want to learn how pop can solar panels for home heating work.

The following page shows complete specification of parts and material needed for building of solar panel.

Important note: Our solar system is not able to accumulate thermal energy after it is produced. When it′s sunny, the solar collector produces heat, but it is necessary to use it immediately for heating the air inside the house. If the sun does not shine, it is necessary to interrupt the supply of air in the solar collector, because otherwise the room will begin to cool off. This can be solved in a simple way – by installing the valve, which will reduce the heat loss to a minimum.

Differential thermostat (snap disc) controls the fan. This thermostat can be bought in better-equipped electronic component stores. The unit has two sensors. One placed inside the top opening for warm air, the other inside the lower opening for the supply of cold air in the solar collector.

If you set the temperatures carefully, solar panel can produce an average 2 kW of energy for home heating. This generally depends on how much sun do you have during the day.

Dress rehearsal of solar collectors carried out in the backyard before installing the system on the house. It was a sunny winter day, no clouds. As a fan is used a small cooler extracted from a faulty power supply of PC. After 10 minutes in the sun from the solar collector is out hot air temperatures of 70 ° C! The test results have encouraged us to install solar heater on the house as soon as possible.

After completing installation of collector, the outside temperature was -3 ° C, and from the solar collector is coming out 3 m3/min (3 cubic meters per minute) of heated air. In the home version we used more powerful fan than for the test. Heated air temperature went up to +72 ° C. Temperature was measured by digital thermometer. To calculate the heating power of the collector, we took the air flow, and average air temperature exiting from the device. Calculated power that the solar panel produced, was approximately 1950 W (watts) which is almost 3 HP (3 horsepower)!!!

CONCLUSION: Considering that the results are quite satisfactory, we can conclude that this DIY solar panel is definitely worth making. The collector, at the very least, can be used for additional heating of our home, and it is up to you to calculate and figure out how much savings you can achieve.

Making Cheap, Inexpensive DIY Solar Panels at Home Mike Davis is an astronomer. To practice his hobby away from the light-pollution of cities, he bought some land in a remote part of Arizona. But there was a problem: No electricity. But he′s a resourceful fellow. He built some home-made solar panels using inexpensive blemished and damaged solar cells from eBay! That might be even cooler, though less romantic, than the couple who got their solar panels via their wedding registry.

Read on for more photos and some technical details to give you an idea of how he did it.


I bought a couple of bricks of 3 X 6 mono-crystalline solar cells. It takes a total of 36 of these type solar cells wired in series to make a panel. Each cell produces about 1/2 Volt. 36 in series would give about 18 volts which would be good for charging 12 volt batteries. (Yes, you really need that high a Voltage to effectively charge 12 Volt batteries) This type of solar cell is as thin as paper and as brittle and fragile as glass.

A solar panel is really just a shallow box. So I started out by building myself a shallow box. I made the box shallow so the sides wouldn′t shade the solar cells when the sun comes at an angle from the sides.

Next I cut two pieces of masonite peg-board to fit inside the wells. These pieces of peg-board will be the substrates that each sub-panel will be built on. To protect the solar cells from the weather, the panel will have a plexiglass front.

I laid out the cells on that grid pattern upside-down so I could solder them together. All 18 cells on each half panel need to be soldered together in series, then both half panels need to be connected in series to get the desired voltage.

I used a low-Wattage soldering iron and fine rosen-core solder. I also used a rosen pen on the solder points on the back of the cells before soldering. Use a real light touch with the soldering iron. The cells are thin and delicate. If you push too hard, you will break the cells.

Here′s what it looks like from the front.

Here I am testing first half panel outside in the sun. In weak sun through clouds the half panel is producing 9.31 Volts. YAHOO! It works! Now all I had to do is build another one just like it.

I drilled a hole in the back of the panel near the top for the wires to exit. Each solar panel in a solar power system needs a blocking diode in series with it to prevent the panel from discharging your batteries at night or during cloudy weather. I added a polarized two-pin jones plug to the end of the panel wires.

Here is the finished product, producing 18.8 volts and 3.05 Amps in the sun.

How much did it cost?

Not bad, though of course there′s a lot of labor needed to actually build the thing, and you need the skills in the first place. Not a project for everybody, but those with the courage will certainly have a lot of fun.

This is just a quick overview of the project. If you want more, please visit Mark′s website linked below. There′s a lot more details and more photos about how he built his inexpensive solar panels.

Last Thanksgiving my sister was coming out to Arizona to visit my new home for the first time. I was looking forward to showing off our homemade hot water heating system and treating Caroline to a refreshing solar shower. Well, about a day before she was due to arrive we had a sudden and early overnight freeze. We woke to discover that the collector had been disabled by a burst pipe. In practical terms, that meant no hot water.

Our week long Thanksgiving vacation would now be devoted to building a newer and more efficient hot water system that would better withstand cold temperatures. Caroline worked with us all week, but sad to say, we did not finish before she departed and she has not yet enjoyed the pleasures of a solar shower.

This diagram shows what we set out to build. Click here to see the illustration full size.

Getting Started

Our first step was to get a used hot >water heater. So Caroline and I emptied out the back of the station wagon and headed over to Porfie′s Thrift. Porfie had about 10 tanks to choose from. They were all outside and kind of beat up looking, but he swore that they all worked and that none of them had any leaks. We spent about $20 on a smaller tank, loaded it up and took it home to see if it would work.

Preparing the Tank

Once home, we stripped off the outer enclosure and insulation and revealed the metal tank. Next, all of the old pipe fittings had to be removed. This task was actually pretty tricky because many of the pipe threads were stuck after years of rusting while exposed the elements. Another challenge we encountered using an old tank was a build up of sediment in the tank′s bottom. The sediment dried and solidified in the bottom of the tank and was difficult to remove, though it was done successfully by rolling and rocking the tank back and forth. Then we filled the tank to rinse it, and happily it was leak-free!

Once stripped and cleaned, the tank was thoroughly sanded and then spray painted black. We put several coats of spray paint on to give it maximum coverage. The spray paint was necessary to protect the metal tank from exposure to moisture and to increase the tank′s absorption of heat. The appropriate fittings were then secured and extra holes plugged. There are 2 hose fittings, a pressure release valve, and a drain spigot.

Constructing and Insulating the Collector Box

After working on the tank, we built the collector box. Our measurements were calculated to accommodate the size of the glass, the size of our tank, and our desire for optimum solar exposure. Based on the sun′s path we determined that the best angle for the glass to sit was 20˚. Once the frame was built, we affixed plywood paneling to the interior of the structure. Then all the interior seems were caulked and we primed and painted the wood.

Next, recycled Styrofoam pieces were cut and wedged into the frame structure to serve as insulation. We also added an additional layer of cardboard beyond the Styrofoam to increase insulation even more. We save Styrofoam, packing peanuts, and bubble wrap to recycle as insulation – we love materials that you don′t have to buy! We′ve also learned that insulation is key to maintaining heat.

After insulating, we painted the outer paneling and affixed it to the outside of the frame. The collector box is essentially a plywood box within a larger plywood box with a layer of Styrofoam as insulation in between.

Tank Supports and Glazing

Before installing the tank we cut 2x4s to match the tank′s curve and firmly fastened them into the collector box. These supports were designed to hold the tank and to bear a considerable amount of weight. We used a recycled sliding glass door for the collector′s glazing. Our glazing is single pane, however double paned glass is preferred for its superior insulating properties.

Installing the Tank

After the box was built and mostly painted we put the ready tank into place.

Then the water supply and return lines were attached from the house into the collector′s storage tank. Cold water flows into the tank from the trailer′s water system. Sun strikes the water storage tank and heats the water. The hot water floats to the top and the coldest water remains at the bottom of the tank. A hose leading from the top of the tank carries the hottest water into the house. Later an overflow hose was attached to the TPR valve to carry excess pressure out of the collector.

We lined the interior with reflectix insulation to direct maximum light towards the tank, and to further insulate the box. Because reflectix is reflective the sun is directed to strike the bottom and back of the tank, which would normally be in shadow. We also lined the top edge of the box with foam insulating tape before putting the glass in place.

With all the parts in place and Caroline long gone, we put the collector to the test. Our first full day of sunlight produced hot water and we were back in business. This very batch collector served us all winter and is still in operation. At night we took to covering the collector with a sleeping back to reduce heat loss, even so hot water was rare on winter mornings. With the majority of the pipes inside the collector, we had no more frozen or burst pipes. In the spring we encountered new and different challenges. With longer and more intense sun exposure our homemade hot water heater has become almost too efficient. Water is at scalding temperatures at the height of the day, and the CPVC hoses used for water intake and outlet have burst from heat and pressure! We have come to the conclusion that metal pipes will be necessary, as well as an anti-scald system.

All in all we are happy with the performance of this collector. I think it cost a little more than the first one, but it is much more efficient. I would recommend it as an excellent source of hot water, or as a supplement to conventional water heating systems.

That′s not to say that hot water experiments don′t have their challenges! Our homemade collector is under constant repair and revision.

Many factors have decided that between renewable (ecological as well), and conventional (non-renewable and non-ecological)
energy sources, the first choice is always conventional energy source with profit as the only important criterion. For example, high
profit is obtained by monopoly on strategic crude-oil reserves. Keep on reading to see how a small man can make a difference.

Ingenious solution shown on the site can solar panels served as inspiration to build “home-made” efficient solar collector.
Basically, it is incredibly simple and cheap solar panel for supplemental home heating, which heats the air directly.
The most interesting is the fact that collector is almost entirely constructed out of empty aluminum cans!

Housing for solar collector is made of wood (plywood 15mm), while its front is 3 mm (0.12 inches) Plexiglas/polycarbonate (you can use tempered glass as well). The back of the case set is made of 20mm rock wool (or styrodur) as insulation.

Solar absorber is made out of beer and soda cans, painted in matte-black paint resistant to high temperature. The upper part (cover) of cans is specifically designed to provide greater efficiency in heat exchange between the cans and the passing air.

When it is sunny, regardless of outside temperature, cans and inside air heat up very quickly.

The fan draws cool air from the room. The air then passes through the filter and check valve, which ultimately goes into the bottom hole through the aluminum insulated pipe. For the purpose of directing and distributing air through the solar panel, there are separate suction boxes made of aluminum sheet 1 mm (0.04 inches). These boxes are located on the lower and upper part of structure. The bottom of the collector′s box has a duty to direct air to the tunnels made out of cans, and in the upper part of the direct air from the cans toward the mouth to drain the heated air.

For detailed instructions and steps how to build your own solar panel for home heating please visit DIY SOLAR PANELS website.

Intro Solar Heater
This is a solar air convection heater for my garage that is powered by the low angle winter sun. It′s easy to build and it works very well. With enough building insulation, this can be a primary heat source with a secondary needed for cloudy days. The idea and design is from Mother Earth News December/January 2007

Ingredients:
2×8 lumber
2×6 lumber
2×4 lumber
2×2 lumber
glass, plexiglass, or some kind of clear material. black aluminum window screen caulking, paint, screws, lag screws, staple gun + other tools

I have some results on temperature differences from the first weeks of operation. Just like when you put up your first wind generator, the wind won′t blow for days/weeks, I had overcast and mostly cloudy weather the first few days operating this thing. The heater puts out 87 to 104 degrees F at the vents on partly cloudy days to sunny days. The uninsulated garage hits about 17 to 30 degrees F above outside temps, very comfortable for me. It seems the colder it is outside, the bigger the temperature difference between the garage and outside. If you want more heat in an uninsulated area I would recommend possibly 1/3 more collector area than the ratio I give in the instructions. Seal up any drafts, it will do a lot to hold the heat. This thing works great.

Step 1 Frame and Fit
Make a box to mount on the wall of building (A south wall, SE and SW also can work.) This should be mounted vertically on a wall; the higher in the sky summer sun won′t hit it as directly as the low winter sun. The walls of the box are 2×6 lumber; the angled roof of the box is a 2×8. I found it good to pre-build the box on the ground and then mount it to the wall. Make the box based on stud spacing in the walls; I have 24 studs, so my box is 8′ wide with vents cut into four sections.

I sized the solar collector based on the numbers from the Mother Earth article where the guy built 160sq ft. of collector for his 700 sq ft building; using that ratio I built a 48 sq ft collector for my 200 sq ft garage.

Step 2 Paint and Add Screen Mounting Boards
Paint the wood and then mount the boards that the aluminum window screen will mount to. Insert a 2×4 horizontally near the bottom leaving room for vent holes, insert 2×2 horizontally at the top; make it even with the 2×4 (look at the drawing to understand this better.)

I notched the middle board for a 2×2 that will later support the glazing.

Step 3 Mount to Wall and Seal
Use a level, floor jack and support wood to set it straight. Have a neighbor hold it while pre-drilling holes from the inside of the building for the lag screws. I used six 4 lag screws.

Seal the box from the inside with window and door foam. Also seal the bottom 2×4 that holds the screen.

Step 4 Cut Vents into Wall
Cut the holes in the wall like in the diagram, a vent on the bottom and on top for each stud section. Watch out for electrical wiring, etc.
My vents are 4 x 16
The cuts are not pretty, use foil tape to trim the inside edge of the vents

This was the toughest part because I didn′t have a good saw.

Step 5 Install Metal Window Screen
Cut and staple black metal window screen (two layers) to the wood inserts in the box.
Note, this needs to be metal window screen for good heat exchanging; fiberglass screen won′t work well.

I used 48 wide screen and had to trim the edge some with a utility knife.

Step 6 Install Glazing and Vent Valves
Install glazing and seal it. I used corrugated PVC; it comes in 8′ x 24 sheets for about $12/sheet (2007 pricing.)

On the top vents in the building you′ll need to put a flapper valve made from plastic sheeting or a trash bag, this keeps the warm air from leaving at night as the heater would work in reverse. Also put some screen on the vents to keep most of the critters out and to keep the plastic valves from sucking into the vent.

Extra notes
Using recycled wood and some on-hand hardware, I spent around $100 for this; now I′m enjoying free heat.

Ducting with a fan and a thermostat switch is what they use on commercial versions installed on homes. That works well for precise heat control. I like convection, no moving parts; and I will just close the vents when the weather gets warmer with some cardboard stapled to the wall.