How does Solar PV work?
A5. Photovoltaic (PV) is the term used to describe semi-conducting materials that generate electricity when exposed to daylight. When sunlight shines on to a solar PV cell, the cell material absorbs some of the light particles. When the photon is absorbed, an electron is freed from the solar material (silicon). The release of electrons creates a flow of electricity between the two layers. Metal contacts in the panel take this electricity away as a direct current (DC).
When some materials are exposed to sunlight, they release small amounts of electricity. This is known as the photovoltaic effect. When describing solar cells, the photovoltaic effect is the conversion of sun energy into electricity by the cells. This is how it works. Sunlight is composed of photons, or particles of solar energy. These photons contain various amounts of energy corresponding to the different wavelengths of the solar spectrum. When photons strike a PV cell (solar module), the energy of the photon is transferred to an electron in an atom of the cell, which is made of a semiconductor material. With its newfound energy, the electron escapes from its normal position on the atom and becomes part of the current in an electrical circuit. When this happens, the electron creates a “hole.” Special electrical properties of the PV cell, specifically a built-in electric field, provide voltage that drives the current through an external load, such as a appliance.
