The excuse that you would love to have a solar panel but it is very expensive is no longer valid: we teach you how to make your solar panels (photovoltaic and solar thermal) in a simple way, in a good, nice and cheap way.


A panel of photovoltaic energy

Among the  most valued solar panels , there are  photovoltaic , that is, those that generate  electricity . While you find the simplest from 200 euros on large areas of materials for construction and home, build your own even cheaper, and gives you the satisfaction of understanding how they work and have done it yourself. Although its use will always be for ‘home’ purposes, such as recharging the car’s battery, turning on some lights in your home, and so on. We tell you how to do it:


– A base of one square meter of any material that does not transmit electricity. Some people prefer wood, but it weighs more than others like acrylic, for example. You can find them well on large surfaces of construction materials, or in stores dedicated to plastics.     

– Solar cells. Of sale especially in online stores like e-bay and others similar. They tend to be cells with some tare, since the new ones are very expensive (although there are also some for sale). They are easy to find and inexpensive, and they sell them loose or as a kit ready to prepare a panel (from 2.50 euros the cell of 2.36 W and around 30 euros the kit of 36 cells, in total 93 W) . For a panel of about 18 W – which serves us for example to recharge a car battery – we need between 32 and 36 cells.

– Low power soldering iron.

– Hot melt adhesive or silicone and a blocking diode. The glue and the diode are usually included in the kits.

– Plexiglas the size of the panel (two, one for each side).

– Painting to protect the wood.

Step by step procedure

After protecting the base of our panel with paint (if it is made of wood) so that it does not suffer from atmospheric conditions (since our panel can last for years), the first thing we will do is place the solar cells that we have on the base. If you have previously made some marks, it will be easier for you.

It is important that we buy the cells without wax (it is usually used to protect them in transport, since they are very delicate), since otherwise we will have to take care of removing this wax, which is a cumbersome process.

The cells should cover both the front and back of the panel, that is, if we have 36 cells, we will put 18 on one side and 18 on the other. It is good to always have some extra cells, since they are fragile and we can break more than one.

We must unite them together by the negative and positive poles respectively. The cells usually bring the wires or tabs to make the connection, which will make the job a lot easier (check this detail when buying).

We must also weld them together so that they are well joined (you can do it with a low power welder taking care not to damage the cell, or, if you do not want to weld, with hot melt glue). This we will do with the cells looking down. Then, carefully, we turn them over and stick them to the panel with silicone, following the marks that will serve as a guide.

Next, we need to protect our panel from the inclement weather and a good way to do it is with a Plexiglas or any plastic sheet, which we will put and screw over our circuit.

The system also needs a blocking diode so as not to discharge at night or cloudy days. Finally, we will connect the cables to the socket and the panel will be ready to be used.

A solar thermal panel

Other panels in great demand are  solar thermal energy :  those used to heat water. We suggest a very simple model to do yourself, even with your children (it is a good exercise to teach them the thermal energy of the sun). It is simple and inexpensive.


– A sturdy cardboard box (where 1.5 or 2 liter bottles fit)

– One or several 1.5 or 2 liter plastic bottles.

– Aluminum foil

– Celofan paper

– Black paint and paint brush

– Scotch tape

Step by Step:

Clean the bottles and paint them with black paint. Then disassemble the cardboard box and line its interior with aluminum foil, which you can glue to the cardboard. The size of the box must be adjusted in such a way that the bottle (s) do not move inside it.

Fill the bottles with water to ¾ parts and press them so that the water rises to the top. Tápalas with force, cover them with cellophane paper and put them inside the box. Stick them with any adhesive tape so they do not fall out and close the box.

Put it somewhere in the house facing south, where the sun shines, tilted about 45 degrees from the ground to take advantage of the sun’s rays. Between two and five hours later (depending on the sun), you will have hot water to prepare an infusion, wash the dishes, or give the use that you see fit.