As an inexhaustible and free source for obtaining energy resources, solar energy is positioned at this time as one of the most cost-effective energy forms from the standpoint of the private individual.

There are currently two systems in the world for the capture of solar energy and its conversion into thermal energy: flat-plate collectors and evacuated-tube collectors, as presented at CONSTRUTEC by Aplicaciones Solares Apolo.

Evacuated tube solar collectors have been developed with aerospace technology by Daimler-Benz Aerospace. Unlike those marketed previously in Spain, these collectors have a high mechanical strength. For this purpose, they have 2.7mm thick glass, besides completely innovative technology in relation to direct metal-glass welding, which endows them with a long useful life. The technological development with which they are manufactured enables them to operate with a solar radiation level of barely 160 W/m² and to be used in places with extreme temperatures. They are well known in regions of Tibet and the South Pole.

Unlike the flat-plate collectors that were used hitherto, evacuated-tube collectors provide complete full architectural integration into the building, with hardly any efficiency losses, as the direct flow collector does not need a slope and can be installed with the tubes in any position (horizontal or vertical) and for the collector heat pipe a minimum angle of inclination of a mere 15º is required.

Reduction of polluting gases

The use of thermal collectors in the production of hot water for such applications as sanitary hot water, heating, air conditioning, swimming-pool climatisation, industrial uses, etc. makes it possible to cover more than 70% of the conventional energy needed, depending on the area, with the resultant reduction in the emissions of polluting gases and the not inconsiderable energy saving.