PV converts sunlight into electricity using a semiconductor material (normally silicon). When like strikes the cell a portion is absorbed within the semiconductor material knocking electrons loose and allowing them to flow. This results in an electric current and thus electricity production. PV panels primarily absorb the visible portion of the light spectrum.
PV panels are normally connected to an inverter to convert from DC (Direct current) to AC (Alternating current) and subsequently the electricity is fed into the power grid.
The PV panels may also directly run devices with DC power such as solar powered calculators, or lights. The DC electricity can also be stored in batteries
Commercially available PV panels are able to convert available sunlight into electricity with optimal conversion efficiency of around 15%, with some panels able to reach as high as 20%.
It is important to note that a panel rated at 200Watts will not consistently provide 200Watts of electricity throughout the day. The 200Watt rating is based on maximum summer sun radiation level of 1000W/m2( 317.1Btu/ft2) in an ambient temperature of 25oC / 77oF. So on a clear summer day a 200Watt panel can be expected to provide around 0.7 - 0.8kWh of electrical energy
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