Abstract :
Wind energy. It´s clean. It´s renewable. Its potential is enormous. But to draw energy from the wind and send it to people´s homes reliably and efficiently, you have to know when the wind will blow and when it won´t. When it stops or changes rapidly, you have to be ready to substitute power from another source. And because such sources aren´t always available at a moment´s notice, you need this information many hours and even several days ahead. None of this matters much if the wind supplies only a small percentage of the electricity going into the power grid. But several countries have already gone far beyond that, and more will soon, as wind is now the fastest growing source of energy in the world. Denmark already gets 28 percent of its electrical power from the wind and has at times drawn all of its electrical energy from wind turbines. The wind is already providing 20 percent or more of the electricity for several U.S. states, including Iowa, Kansas, and South Dakota. Colorado, for example, has at times obtained 60 percent of its electric power from the wind. And the United States as a whole will likely produce 20 percent of its electricity from wind power within 15 years.