Energy - põhjalik referaat energiast
Later, people built windmills
to grind wheat and other grains. The earliest known windmills were in Persia (Iran). These
early windmills looked like large paddle wheels. Centuries later, the people of Holland
improved the basic design of the windmill. They gave it propeller-type blades, still made
with sails. Holland is famous for its windmills.
American colonists used windmills to grind wheat and corn, to pump water, and to cut
wood at sawmills. As late as the 1920s, Americans used small windmills to generate
electricity in rural areas without electric service. When power lines began to transport
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electricity to rural areas in the 1930s, local windmills were used less and less, though they
can still be seen on some Western ranches.
The oil shortages of the 1970s changed the energy picture for the country and the world. It
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