WIND ENERGY

  Origin: wind is simply air in motion. It is caused by the uneven heating of the earth’s surface by the sun. It generates the air cycle.

Extraction: the wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity.

With the new wind machines, there is still the problem of what to do when the wind isn’t blowing. When this happens, other types of power plants must be used to make electricity.

Wind power plants, or wind farms as they are sometimes called. Wind plant owners must carefully plan where to locate their machines. One important thing to consider is how fast and how much the wind blows. Good sites for wind plants are the tops of smooth, rounded hills, open plains or shorelines, and mountain gaps that produce wind funnelling.

  Uses: in 2005, wind machines in the United States generated enough electricity to power a city the size of Chicago. New technologies have decreased the cost of producing electricity from wind, and growth in wind power has been encouraged by tax breaks for renewable energy.

Producer regions: The United States ranks third in the world in wind power capacity, behind Germany and Spain and before India. Denmark ranks number five in the world in wind power capacity but generates 20 percent of its electricity from wind. Most of the wind power plants in the world are located in Europe and in the United States where government programs have helped support wind power development.