Wind energy technology generates electricity using the renewable resource of wind rather than fossil fuels. The types of wind energy technologies range from vast commercial wind farms connected to an electrical power grid to small residential wind turbines that power a single home. Although wind power has historically been used to pump water and grind grain, wind energy technology is today mainly focused on the production of electricity, both large scale and small. Power generation occurs when the wind turns the blades of a rotor. This, in turn, runs a generator, creating electricity.
Large-scale, commercial wind energy technology usually takes the form of wind farms. These consist of multiple wind turbines connected to the electrical grid, providing power from renewable wind energy for homes and businesses in the region. Wind farms require adequate land and must be placed in areas that have sufficient wind resources. They usually use large, three-bladed turbines mounted on towers that are generally between 150 and 300 feet (45 to 90 meters) above the ground to capture the faster winds. The land below the turbines can be used for agricultural purposes, such as grazing animals or growing crops.
A similar wind energy technology utilizes the stronger winds found over the ocean. Offshore wind farms are currently situated in shallow waters, but research continues on designing cost-effective deep-water wind generation facilities. Some design modifications are required for the turbines and towers due to the harsher conditions offshore. Turbines are generally larger than those on land-based wind farms and have special technologies to reduce corrosion and maintenance. Offshore wind farms are generally found near large population centers and are connected to the power grid by underground cables.
Medium-scale wind energy technology is used on a community level. Wind turbines may power public buildings, such as schools or government facilities. They are also used to provide power for industrial and commercial facilities. Medium-scale wind generation units may be connected to the grid, but are more frequently used to provide power to single sources. This class of wind turbines has a smaller diameter, height and power production than the large-scale turbines used in wind farms.
The smallest scale wind energy technology is used for residential purposes. These turbines provide electricity for homes, farms and a variety of other facilities with relatively low energy consumption. Wind energy technology companies continue to improve the design and efficiency of residential-sized units. Although most small turbines are based on a standard blade design mounted on a tower, others use rotating barrels or vertical axis turbines and might be mounted directly on the building. Many residential wind turbines create more power than the home uses, and the excess electrical power might be purchased by the utility company.