All we have noticed in our flesh, even in the coldest winter day, as the sun warms us to shine. One of the earliest uses of solar energy is this. It is customary to place concrete tanks filled with water rooftop in cottages for the day the water is warm. Or just use open the blinds to let the sun coming through the window the house warm.
With these same principles we can make a solar oven solar heater so we blanch the house in daylight hours, stealing more timid performance rays of winter. And we can even make ourselves a small standalone installation we heat the house even without being us inside to find her returning warm. This can be very useful in second homes, which are always on our return we received very coldly.
All the material we need is easily achievable, but can also be reused from old installations. We need:
A large sheet metal
A sheet of insulating cork
Asphalt or the like fabric
An exhaust fan bathroom 12V
A curtain of extracting that open to circulate air
Two square or rectangular tubes
The idea is to create a black box that will heat the air inside. Thanks to a small solar panel and fan 12V can recirculate the hot air inside our house. With the advantage of being a solar panel, the stove will only work when the sun falls on the whole, so we have an autonomous solar heater.
The box can hang on the exterior wall on which impinges the sun or on a roof facing south as possible. The air will circulate inside the stove to heat must be removed from the house and returned to her once hot. That is why we need to install the two pipes through the wall (or window) or ceiling, as our chosen option.
We start from the sheet metal to have. Imagine you have a sheet of 1 m2, 1 meter long by 1 meter wide. This will be the top of the box we want to build.
Our insulation will cut cork or with the same dimensions, in this case a square of 1 x 1 m. Thus we face opposite to the plate. From these two, the remaining four faces configured properly cutting the cork, for example be 4 pieces of 1 meter long by, for example, 20 cm wide. We join these 4 pieces to the large cork with silicone or glue we have. And so we get a box with no lid. This is the line we internally with bitumen or similar fabric, getting some tightness. No need to be tight but the better we do less hot air will escape us.
The next step is to prepare the openings through which enter and leave the air. Mark circles or squares approximately equidistant from the center and close to the walls of the box, as they have the tube.
In parallel we can prepare the cover, the sheet metal.
We apply black paint to better capture the sun’s heat. Each color we see what their color because it reflects the corresponding wavelength of sunlight, except for the black, which absorbs all, is why the paint it black is improving the capture of light and therefore energy it carries.
We have prepared the lid of the box. We only need to join you source the fan motor, a small solar panel 12V. We can fix it over the top or install it apart, but this way we get that the set is autonomous also only work when insolated, which ultimately is what we want.
In the scheme there is fixed a cheap solar panel small, like this: which is enough to move a small 12V fan. If we do so, and prepare the wiring through the metal plate and fix the panel to it, for example by sticking the module frame to the plate with waterproof glue and heat.
We shall prepare a third of the whole, the inlet and outlet air. The tube that draws air from the house will be located at the bottom and assemble its end the curtain that opens to pass air. This curtain we install air circulation allowing foreign toward the house and not vice versa.
With the other tube will do a similar job. We will set the fan at its end and so we allow the movement of air through the stove when the solar panel will apply the necessary 12V. If reverse assembles, exchanging only gets positive and negative movement in the right direction.
It remains only to fix the various parts of the assembly, sealed with silicone to make it as tight as possible and mount it in the location that suits us.
We therefore well our complete solar heater.