Already 40 square metres of roof surface are sufficient to cover the annual power need of a 4-headed family with solar modules. No other country uses solar energy for energy production as intensely as Germany on small and big roofs just as on free-fields.
A solar module converts the light of the sun directly into electric energy. As the most important components, it contains several solar cells (mostly on silicon base) or is made out of solid-state materials in thin layer technology. Solar modules are panelled individually or in groups in PV plants connected to the grid or used by independent consumers.
An inverter is an electric device that converts DC voltage into AC voltage direct power. Inverters reach efficiencies of up to 98 per cent, they are applied where an electric consumer needs alternating voltage, but where only one DC voltage is available, such as in a car battery; or where the output of a DC voltage source shall be fed into the a.c. network, as in photovoltaics.