Wind energy is by far the most cost effective and environmental friendly form of renewable energy, however, it may never be able to supply more than a limited percentage of global energy requirements. It is not possible to get the entire requirement out of the limited space that is given to wind energy mills. To be able to fulfill the complete global requirement these wind mills would have to be erected in just about every place. Nevertheless, the growth and cost efficiency of wind energy has been increasing at a steady pace.
Wind energy is the conversion of kinetic energy in the wind to mechanical energy of a rotating shaft using a wind turbine, and then that same mechanical energy is converted into electrical energy using a generator. In large-scale windmills, the generator is attached to the turbine shaft with the help of gears and complex power electric controls can convert the electricity produced into the optimal frequency and optimal voltage that is required.
According to a recent survey, in the year 2008, the global capacity of wind power generators was approximately 121.9 gigawatts and the energy produced out of that was approximately 260 Two, which is about 1.5% of the total global requirement and it is still growing steadily, having become twice the previous production in just 3 yrs between 2005 to 2008.A lot of countries have done wind power penetration at very high levels thanks to the government subsidies provided to them. Denmark produces 19% of stationery electricity, Spain and Portugal produce 13%, and Germany produces 7%.The survey done in may 2009 states that more than 80 countries around the world have started using wind power commercially.
Large-scale windmills are now connected to electric power transmission units, which produce electricity commercially for domestic and industrial use. The smaller units are sufficient to supply electricity to rural area that is isolated. There are some utility companies, which buy back the surplus electricity produced by these small turbines
Wind energy as a source of electricity is a very attractive source because it is the best alternative to fossil fuels, which are rapidly running out, moreover, it is found abundantly in nature, it is renewable, it is distributed widely, and it is cost effective, clean and produces no green house gases and harmful emissions. However, wind power is not dispatch able, which means it is not available all the time and when available the entire energy needs to be consumed.