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Solar explained Where solar is found

Solar energy is sunshine

The amount of solar energy that the earth receives each day is many times greater than the total amount of all energy that people consume each day. However, on the surface of the earth, solar energy is a variable and intermittent energy source. The amount of sunlight and the intensity of sunlight varies by time of day and location. Weather and climate conditions affect the availability of sunlight daily and on a seasonal basis. The type and size of a solar energy collection and conversion system determines how much of the available solar energy we can convert into useful energy.

Map of Concentrating Solar Resources in the United States showing greatest concentration mostly in the areas from western Texas westward to California and northward to Washington, Idaho, Montana and the western parts of the Dakotas; with moderate concentrations in the lower southern tier of the country from Florida through Maryland.

Source: National Renewable Energy Laboratory, U.S. Department of Energy

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Map of Photovoltaic Solar Resources in the United States showing greatest concentration mostly in the areas from western Texas westward to California and northward to Oregon, Idaho, and Wyoming

Source: National Renewable Energy Laboratory, U.S. Department of Energy

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Solar thermal collectors

Low-temperature solar thermal collectors absorb the sun's heat energy to heat water for washing and bathing or for swimming pools, or to heat air inside buildings.

Concentrating collectors

Concentrating solar energy technologies use mirrors to reflect and concentrate sunlight onto receivers that absorb solar energy and convert it to heat. We use this thermal energy for heating homes and buildings or to produce electricity with a steam turbine or a heat engine that drives a generator.

Photovoltaic systems

Photovoltaic (PV) cells convert sunlight directly into electricity. PV systems can range from systems that provide tiny amounts of electricity for watches and calculators to systems that provide the amount of electricity that hundreds of homes use.

Millions of houses and buildings around the world have PV systems on their roofs. Many multi-megawatt PV power plants have also been built. Covering 4% of the world's desert areas with photovoltaics could supply the equivalent of all of the world's daily electricity use.

World Map of Solar Resources showing greatest concentration in the southern portion of the Northern Hemisphere, South America, Africa, the Middle East, southern Eurasia, the South Pacific, and Australia

World map of solar resources

Source: United Nations Environment Programme (UNEP), NASA Surface meteorology and Solar Energy (SSE), 2008.

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Last updated: August 8, 2018