A major challenge for the constructors of DIY solar water heaters is the collector. How to make an efficient solar panel? We have found different ideas, from empty pet bottles and cans to Fresnel lenses. Some of them are presented here for your consideration. At the end of each example is a reference link where you can find more details.
Copper is superior in thermal conductivity so that it can be used as the material for solar water heaters.
Gain some skills while soldering – it is not complicated and may be done as the DIY home project. You will also need a board to attach connected copper pipes to it. Add a glass on the top.
The solar water heater is very compact and looks like a window with pipes inside. Hot water is coming fast, with a temperature above 65 Celsius degrees, even when the air temperatures are between 9 and 11 C. See the full instruction following the link below.
If you want to add some time and money and work as a real artisan, follow instructions and make connected panels. They are more powerful and bring bigger savings as a result. Each panel costs $450-$500 to build.
David Norman from Florida is also sharing his experience with us about a DIY solar water heater adventure.
In his project, the most important material is PEX tubing and the total cost, together with the wooden box painted in black, is $280. The solar system is connected to the standard electric water heater as an alternative source of energy. The bypass valves are used for diverting. This solar water heater is excellent for the summer savings; it is inexpensive and ideal for small households.
Anyone could try to make a solar water heater, but the idea makes a difference.
Jose Alano, a retired mechanic from Brazil, won the Superecologia prize for his invention – the plastic bottle solar water heater. A thermosyphon technology is at the base of the system, i.e., circulation of water without a mechanical pump, caused only by temperature differences. If you want to test this structure, choose a summer or a warmer climate, collect plastic bottles and milk cartons, buy some PVC pipes, small parts, black matt paint... and do it.
Jose has patented his design and put it at people’s disposal, only for not-for-profit use. Check it out here.
How to raise the efficiency of the solar collector?
Many innovators advise making it parabolic. The parabolic trough has a surface covered with a mirror to concentrate sunlight and heat onto its focal point. In the DIY version, you will make a mirror effect using other materials, according to your budget and skills. This small model is made of PVC pipes, covered with a reflective material, and presented by Dan Rojas. His solar water heating system has an insulated storage tank with a heat exchanger, as usual.
This system, which follows the sun, is also parabolic but more complex, inspired by the previous one.
In six videos, his author Andrew Ancel Gray explains how to make the great solar collector - step by step. Four parabolic troughs acquire energy to heat the 80-gallon tank. Dual-axis movements provide the best possible positions using some sophisticated solutions like heliostat, infrared beam break rotation counters. It may look a bit complicated and expensive, but each part has a role, and you get a high-quality solution.
Did you hear about the Fresnel lens?
An old invention originally used to increase the lighthouse light is the subject of research in today’s solar energy concentration technology. Although there are some serious limitations to using Fresnel lenses in solar power plants, solar energy enthusiasts have tested the lens and got results in DIY water heating systems. Check the brief explanation of the principle and see the water heater project made of lens and black painted storage tank. Water becomes hot extremely fast.