Photo voltaic panels convert the sun's energy directly into electrical energy and feed electricity directly into the house. The electricity cannot be fed in directly and an inverter is required to convert the low voltage direct current electricity into high voltage alternating current to make it compatible with electrical fittings that are designed for mains electricity, or to feed electricity into the mains grid.

Most photo voltaic panels fit on the roof surface, but some are incorporated in the roof covering, including flat roof coverings.