Interesting facts on Photovoltaic
The word photovoltaic is a compound of photos (the Greek word for light) and Alessandro Volta (one of the pioneers of electricity). It deals with the transformation of solar energy into electric power and has been used for provision of electricity since 1958.
The core of the photovoltaic system is the solar cell: in the solar cell, positive and negative charge carriers are freed when light strikes the silicon layer of the cell.
The majority of solar cells are made of silicon, whose source material is nothing else than sand (= silicon oxide).
Off-Grid Systems
Off-grid systems (also called stand-alone systems) are photovoltaic systems which are not connected to the electricity network. The electricity they produce is stored in accumulators and available at any time. During daytime the accumulators are recharged. Thanks to the accumulators, stand-alone systems can get by without daylight. They are ideal for isolated regions or areas where it would be economically impractical to connect to the grid (e.g. park lighting or pocket calculators).
Grid-Connected Systems
These are photovoltaic systems connected directly to the grid. Electricity not used domestically is fed into the grid but if electricity needs are not met by the photovoltaic system, then current is provided by the grid.
