Powering Lives

Wind is an important source of renewable energy. This is caused by the uneven heating of the earth?s surface by the sun. During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating winds.

The wind energy is harnessed using a wind turbine. In a wind turbine, the wind flows over the airfoil shaped blades of the turbine causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity. Wind power investments have grown in recent times. Although wind produces only about 1% of worldwide electricity use, it is growing rapidly. In fact, it is increasing more than fivefold globally between 2000 and 2007. By 2010, the World Wind Energy Association expects 160GW of capacity to be installed worldwide, up from 73.9 GW at the end of 2006, implying an anticipated net growth rate of more than 21% per year.

The most comprehensive study to date found the potential of wind power on land and near-shore to be 72 terawatts (TW). At the end of 2007, worldwide maximum output of wind-powered generators was 94.1 gigawatts (GW).