A chemical reaction in green plants in which carbon dioxide from the atmosphere combines with water to form carbohydrates, using the energy of solar radiation.
Photovoltaic (PV) effect
The result of electrons being freed from impurities in semiconductors by the quantum energy of light photons, so that the electrons move to generate both electrical potential and current. The principle behind solar cells.
Mechanical energy that exists by virtue of position or potential in a force field — usually that of gravity.
The rate at which energy is delivered or work is done, measured in watts (W). One watt is equivalent to one joule per second.
The energy released by directly burning fossil fuels or consumed at source in electricity generation.
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