Solar cells, also called photovoltaic cells, convert sunlight directly into electricity. Photovoltaics (often shortened as PV) gets its name from the process of converting light (photons) to electricity (voltage), which is called the photovoltaic effect. This material, usually made of silicon but potentially other polycrystalline thin films, generates a direct current when sunlight hits the panel.
A single PV device is known as a cell. An individual PV cell is usually small, typically producing about 1 or 2 watts of power. To boost the power output of PV cells, they are connected together in chains to form larger units known as modules or panels. Modules can be used individually, or several can be connected to form arrays.
Commercially available PV panels are up to 22.5% efficient at converting sunlight into electricity in optimal conditions, but even in partly cloudy weather, they can operate at 80% of their maximum output.
PV systems may or may not be connected to the electric transmission grid:
- PV systems linked to the transmission grid can supplement utilities energy supply during daylight hours, which normally include the peak energy demand periods.
- Independent PV cells can power a variety of individual items, from personal calculators and streetlights to water pumps on ranches and remote settlements far from power lines.
0 comments:
Post a Comment