The present invention relates to a solar collector for absorbing solar energy and for converting such solar energy into thermal energy. The invention particularly relates to such a solar collector formed from aluminum foil. The present invention also relates to a method for production of such solar collector.
The term "solar collector" in the broadest sense is employed to mean any radiation receiver that responds to electromagnetic radiation and converts it into thermal energy. Examples of such radiation receivers are, inter alia, bolometers, thermal converters, and similar devices. One problem with solar collectors or radiation receivers is bringing the absorption capacity of the surface acted upon by the electromagnetic radiation near to the value 1. Those bodies that have the absorption capacity 1, that is to say that absorb all incident radiation and convert it fully into heat, are referred to as "black bodies". Black bodies or black radiators/emitters in practice are formed by a cavity having a small opening. The walls of the cavity are impermeable or impenetrable to electromagnetic radiation of all wavelengths, so that a radiation equilibrium becomes established in the cavity. Black bodies of this type however are unsuitable for use as solar collectors.