wind is a form of solar energy. winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. this wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.
how wind power is generated
the terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. wind turbines convert the kinetic energy in the wind into mechanical power. this mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity to power homes, businesses, schools, and the like.
wind turbines
wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. simply stated, a wind turbine is the opposite of a fan. instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. the wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
wind turbine types
modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style darrieus model, named after its french inventor. most large modern wind turbines are horizontal-axis turbines.
turbine components
horizontal turbine components include:
blade or rotor, which converts the energy in the wind to rotational shaft energy;
a drive train, usually including a gearbox and a generator;
a tower that supports the rotor and drive train; and
other equipment, including controls, electrical cables, ground support equipment, and interconnection equipment.
