The realization of the solar concentrator uses simple flat mirrors, square and 15 cm of side, like those in sale at a big chain of supermarkets for furnishing, supported from a support in compensated wood having the right inclination apt to focus the light reflected on a prechosen focus plan.

 In order to realize a first prototype of solar panel to concentration it is better to choose dimensions to make it easy realizable, also in function of the normally available materials.

As an example it will convene to realize the chassis of support of rectangular shape using of outlines to you in iron of square section of 2 or 3 cm of side; usually such outlines are sold in bars of 6 meters length, so it will convenient to choose the dimensions like submultiples of such value, as an example 1 meter x 2 meters; in this way it will be convenient to ask to the supplier to subdivide the bar in 2 auctions of 2 meters and 2 auctions of 1 meter of length.

It will be moreover convenient to determine the proportions of the oblique auctions that support the focalization frame of 30 cm x 30 cm on which it will go to converge the solar light with the same criterion; choosing therefore long auctions 2 meters each one, a log of pyramid is obtained with a focale plan approximately 176 cm far from the base panel.

 Finally the dimension of the focalization frame is such to allow the focalization of the single mirrors from 15 cm x 15 cm on one surface of 20 cm x 20 cm, that it concurs to tolerate small errors of guideline of the single mirrors, allowing an edge of 5 cm of material insulator in order to diminish the dissipation of the heat and  to maintain the warm part of the used thermal machine (for example a Stirling motor) to the maximum temperature.

Taking account that, once oriented towards the sun, the surface of the focalization frame produces a shade of the same dimensions, it will be convenient do not install the central 4 mirrors; instead of them will be put opportune light sensors for the optimal control of the panel; altogether the comprehensive panel of the mirrors will have the following shape: 

An other important criterion in realizing such panel is the modularity; that is it will be able to be begun to realize a first central panel of 1 m 1 m and therefore to add to extreme sides of the chassis two panels of 1 m x 0,5 m everyone; subsequently, to flank of every greater side of such chassis two panels of 2 m x 1 m everyone could be added, with i single mirrors opportunely oriented towards the same surface center.

In that latest configuration the total surface would arrive to 6 m² and that one of the mirrors to 4,77 m²; calculating a power of the solar light of a 800 w/m² and total coefficient of reflection of 80%, the conveied thermal power on  the focale plan would be of 3,05 Kw; using a thermal engine working with the Stirling cycle or the Brayton cycle with a rendering of 30% the obtained mechanical power it could be approached to 1Kw of peak.

It is worth the pain observing that in order to obtain the same power of peak by means of photovoltaic panels would have to use an approximately double surface, and that the cost of a photovoltaic panel is gone around around to the 300-350 euro for every 50 watt of peak; the value of such system could therefore be gone around around to the 6000 euro approximately.

Care the total number of used mirrors, this is connected to the intentional relationship of concentration; using sixty or seventy  mirrors a relationship of concentration of approximately 50:1 is obtained, that it assures one remarkable temperature.

Consequently, deciding to realize such concentrator in the maximum configuration it can be used 30 cm x 30 cm side mirrors , equally available near the same aforesaid supermarket chain of  furnishing; in such case three panels would be used altogether place side by side of 2,2m x 1m using 62 mirrors of such dimensions, for a total surface of 5,58 m², improving the total energetic budget.

However also a realization of such concentratore limited to the single panel centers them from 2m x 1m and the conversion of the thermal energy in mechanical energy with a simple steam engine with one expansion (using a single piston) with a not elevated rendering,around to 10%, brings to interesting results; in fact using an alternator from automobile in order to convert such mechanical energy in electrical energy it could be obtained power around to the 100W, useful to recharge the batteries for a nocturnal lighting system or other applications and to use the thermal energy remaining (around to 1Kw of thermal power) in order heating the water; the value in such case could be advanced to the 700 euro for the part electrical worker (to difference of the photovoltaic panels of  equivalent power in fixed position and never optimal regarding the lighting system, the aforesaid concentrator is always found oriented towards the solar light, with nearly a doubling of the effectively obtainable power) and as many for the warm water, being such panel equivalent to one thermal of equal surface, but, with the exception of these, always oriented in optimal way.

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