Wind energy converts kinetic energy that is present in the wind into more useful forms of energy such as mechanical energy or electricity. Wind energy is a pollution-free, infinitely sustainable form of energy. It doesn’t use fuel; it doesn’t produce greenhouse gasses, and it doesn’t produce toxic or radioactive waste.

Windmills that were used to grind grain are an example of early uses of wind energy. Modern uses of wind energy include generation of electricity and pumping water. Current wind energy machines are called "wind turbine generators", "wind pumps", or more generally, "wind turbines".

Wind mills was a common sight in the early days on the country landscape.
The paddle wheel devices were used to harness the wind to pump water up from beneath the ground for cattle to drink. Such wind mills were also used to mill grain at the granaries.
The wind mills are revived in the 1970's in the form of huge bladed machines that are moved by the gentlest of wind of less than 3 mph. These wind machines have been used to power small dwellings. These wind machines . The disadvantage of this source of energy is its limited geographical setting. It can only be taken advantage of where the wind moves continuously as you would have at the coast or in vast flatland.
Denmark is currently the world leader in wind power. By 2030, fifty percent of Denmark's energy could be produced by wind power. Wind power emits no greenhouse gases, but it takes up large amounts of land. In order for it to be a reliable source, scientists must develop better power storage techniques.