Wind Generators

Wind turbines produce wind power by harnessing the wind’s energy. Kinetic energy in airflows can be used to run wind turbines with some capable of producing up to 5 MW of power, but the most cost effective are currently 500 kW – 1.5 MW. Wind turbines have two or three airfoil blades that are mounted to a rotor, which is attached to a main shaft. When wind blows over the airfoils, the “lift” that is created causes the rotor to turn like an airplane propeller. The rotor drives a generator, usually via a gearbox, that produces electricity. The faster the wind speed and the longer the blades the more electricity the turbine generates. Wind turbines are placed on towers to capitalize on more dependable and faster winds.

Wind power has many environmental advantages. There are no air or water emissions; thus wind energy does not contribute to global warming, acid rain or air pollution. Wind turbines do create some noise from the gearbox and the rotating blades. The noise level decreases quickly as distance from the turbine increases. Careful placement of wind systems can mitigate noise concerns.

Globally, wind is the fastest growing of the renewable energy sectors. Over the past decade, global installed capacity increased from 2,500 MW in 1992 to just over 40,000 MW at the end of 2003, at an annual growth rate of near 30%. Most deployed turbines produce electricity about 25% of the time (load factor 25%), but under favourable wind regimes some reach 35% or higher. Wind power is renewable and contributes to greenhouse gas mitigation because it removes energy directly from the atmosphere without producing net emissions of greenhouse gases such as carbon dioxide and methane.

Wind electric generators can be used to power household and institutional needs but often need supplementing with solar or other energy source because they do not produce electricity constantly (it depends on wind patterns).