Photovoltaics
The sun’s energy can be converted directly into electricity using photovoltaic (PV) cells. PV cells can be used for applications as small as watches and calculators and to as large as grid-connected arrays of panels. The great attraction of PV technology is that it delivers electricity at the point of use. For example panels can be integrated into building design to supply the buildings themselves with power.In areas where grid connection or other forms of generation are too expensive or not feasible, PV can be very cost-effective. This may be in remote locations, but could also be in a city center where grid connection may be impractical. For example it can be cheaper to power parking meters with solar energy than with power from the grid.
PV materials are usually solid-state semiconductors. Various forms are used:
· mono-crystalline silicon (crystalline)
· Poly-crystalline silicon (crystalline)
· amorphous silicon (thin film)
· cadmium telluride (thin film).