ENERGY FROM WIND AND WATER
Hurricane or tornado survivors or anyone who has seen pictures of the aftermath of these storms will realize there is enormous energy potential in wind power. The problem is taming this energy so that it is useful without being destructive.
Wind energy is derived from the sun. Because the sun's energy is not absorbed uniformly, some regions of Earth's atmosphere are warmer than others. The warmer air expands and rises; the cooler air contracts and settles. The expanded air is at a lower pressure than the cooler air. The difference in pressure causes a wind to blow. There is a further bonus in wind energy, not attributable to the sun but to whatever caused Earth to rotate in the first place. Earth, in its furious spin, drags some of the air close to it around, causing prevailing winds to blow from west to east.
Humans have made use of this form of energy for millennia. For centuries, ships sailed under wind power until devices were invented which converted wood, coal, or other fossil fuels into the energy necessary to drive a ship.
As early as the 20th century B.C., the Babylonian Emperor Hammurabi planned to use windmills (devices with sails) for capturing the wind's energy and pumping water for irrigation. Notice that despite its end use, we have called the device a windmill. Many centuries later, it was principally used to grind grain between two
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Publication information: Book title: Farewell Fossil Fuels:Reviewing America's Energy Policy. Contributors: Sidney Borowitz - Author. Publisher: Plenum Trade. Place of publication: New York. Publication year: 1999. Page number: 145.