Hightech windmills, some standing 500 feet high when their blades are vertical, hum on the Altamont Pass of California as they produce clean electricity. Wind energy is the world's fastest growing energy source, expanding 25, 35 percent each year. In 2001, roughly 6000 megawatts of new wind capacity was installed around the world, enough to power 2 million American homes.

alternative energy wind electricity north america usa united states california