Wind energy is a special form of the air's kinetic energy caused by solar radiation on the earth's surface. About 4500 years ago the Babylonians were the first to construct a machine, windmill, that converted the wind into mechanical energy; in their case for pumping water. Modern wind power converters are coupled to electric generators with peak powers of up to 5 million Watts (5 Megawatt). This technology promises to deliver a significant part of mankind's energy demand. Build your own little wind-powered generator:
