Wind power is a type of solar energy since it is originated by extreme temperatures of the sun. Each structure of the surface of the earth is heated by solar radiation, but in different paces and in varied dimensions. The earth normally is heated during the hours of the day and cools in the hours of darkness. Heat is liberated in diverse quantities by water, pebbles, soil, structures, etc. causing the surface of the earth and the air close to the surface to be heated. Warm air goes upwards, due to which the atmospheric pressure close to the exterior of the earth decreases, and cold air is drawn towards the surface. This movement of air is known as wind.

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Image Credit: geograph.org.uk