The Difference
In order to save energy right at the beginning it is essential to make use of the energy available directly wherever possible; –Meaning: use the sun’s heat directly without the detour through conversion to electricity (conversion losses appr. 75%) and heat your domestic water or household or industrial process directly.
A comparison between the systems shows the main differences: The efficiency of PV cells substantially deteriorates with higher temperatures. Unfortunately sun input is coupled to an increase of temperature in most high input regions of the world.