Renewable Energy - Wind Energy
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Wind Energy
As the the sun heats up the Earth unevenly, winds are formed. The kinetic energy in the wind can be used to run wind turbines, some capable of producing 5 MW of power. The power output is a function of the cube of the wind speed, so such turbines generally require a wind in the range 5.5 m/s (20 km/h), and in practice relatively few land areas have significant prevailing winds. Luckily, offshore or at high altitudes, the winds are much more constant.
There are now many thousands of wind turbines operating in various parts of the world, with utility companies having a total capacity of over 47,317MW. New wind farms and offshore wind parks are being planned and built all over the world. This has been the most rapidly-growing means of electricity generation at the turn of the 21st century and provides a complement to large-scale base-load power stations. Most deployed turbines produce electricity about 25% of the time (load factor 25%), but some reach 35%. The load factor is generally higher in winter.
Drawbacks
There is resistance to the establishment of land based wind farms owing initially to perceptions they are noisy and contribute to "visual pollution," i.e., they are considered to be eyesores. Many people also claim that turbines kill birds, and that they in general do little for the environment.
Others have argued that they find the turbines beautiful, that turbines out at sea are invisible to anyone on the shore, that cars kill more birds annually and that turbines are continuing to evolve.
Wind strengths vary and thus cannot guarantee continuous power. Some calculations suggest that 1000MW of wind generation capacity can be relied on for just 300MW of continuous power. While this might change as technology evolves, advocates have suggested incorporating wind power with other power sources, or the use of energy storage techniques, with this in mind.
Wind power is renewable.
From Wikipedia.