Solar energy refers to the utilization of the radiant energy from the
Sun. Solar power is used interchangeably with solar energy, but refers
more specifically to the conversion of sunlight into electricity by
photovoltaics, concentrating solar thermal devices, or by an
experimental technology such as a solar chimney or solar pond.
Solar energy and shading are important considerations in building
design. Thermal mass is used to conserve the heat that sunshine
delivers to all buildings. Daylighting techniques optimize the use of
light in buildings. Solar water heaters heat swimming pools and
provide domestic hot water. In agriculture, greenhouses expand growing
seasons and pumps powered by solar cells (known as photovoltaics)
provide water for grazing animals. Evaporation ponds are used to
harvest salt and clean waste streams of contaminants.
Solar distillation and disinfection techniques produce potable water
for millions of people worldwide. Simple applications include
clotheslines and solar cookers which concentrate sunlight for cooking,
drying and pasteurization. More sophisticated technologies concentrate
sunlight for high-temperature material testing, metal smelting and
industrial chemical production. A range of experimental solar vehicles
provide ground, air and sea transportation.
