Wind turbine beside a road. The blades of such turbines are turned by the wind, which produces electricity. Wind turbines are usually sited on hills or beside the sea so that they receive as much wind as possible. Wind power is an important environmentally-friendly alternative to fossil fuels. It produces no waste and is cheap to maintain once it has been set up. The generation of energy from the wind is a long-term alternative to the finite energy supplies of fossil fuels. Land used for wind power generation can normally also be used for other purposes, most often agriculture. Photographed in Andalucia, Spain.