How is sunlight converted to electricity?
A When certain semi-conducting materials, such as certain kinds of silicon, are exposed to sunlight, they release small amounts of electricity. This process is known as the photoelectric effect. The photoelectric effect refers to the emission, or ejection, of electrons from the surface of a metal in response to light. This is the basic physical process in which a solar electric or photovoltaic (PV) cell converts sunlight into electricity. (All SunPower solar systems are PV-based.) Sunlight is made up of photons, or particles of solar energy. Photons contain various amounts of energy, corresponding to the different wavelengths of the solar spectrum. When photons strike a PV cell, they can be reflected or absorbed, or they can pass right through. Only the absorbed photons generate electricity. When this happens, the energy of the photon is transferred to an electron in an atom of the PV cell (which is actually a semi-conductor). With its newfound energy, the electron escapes from its nor
