Wind energy is a form of renewable energy produced through machines that use wind as their power source. Wind energy is only possible because of the sun.
The sun heats the atmosphere, but it doesn't do it evenly. This process, along with the rotation of the earth, causes winds that scatter across the varied surface of the earth. That wind can be harvested by wind turbines. The wind turns the turbines, which generates electricity.
The turbines are connected to shafts. When the turbines turn, the shaft turns. The shaft then turns a generator. The turning of the generator creates a flow of electrons, which is electricity. Wind turbines automatically shift to harness the most wind power, based on which direction the wind is blowing.
Two basic types of wind turbines exist. Some spin vertically, like the giant turbines on wind farms that look like pinwheels. Other turbines spin horizontally; these types can be used on the tops of buildings to generate energy.
Turbines on wind farms can produce up to several megawatts of energy, though some produce less. They are grouped together to produce power on a grid. Blades on a large vertical turbine can be as long as 100 yards. Smaller turbines produce less than 100 kilowatts of energy. These types are used in residential areas for homes, and they are usually employed by themselves, though sometimes they work in conjunction with power from the city.
Energy that is created by bulk-powered wind turbines is either directly used or placed onto the nation's power grid and stored for future use. Smaller single turbines can be used to provide energy to homes that are located in areas that do not have access to the electrical grid.
The wind program, sponsored by the U.S. Department of Energy, works to create land-based and offshore wind power, in an effort to create clean energy power that is renewable and cost effective.