The Power of Wind

The Power of Wind

Over the last few decades America has become more and more dependent on resources that are destroying our environment and economy. We rely too much on oil from foreign countries, gas for our cars and houses, and plants that are creating too much pollution. This country needs to start looking for more renewable sources; which is where wind comes into effective use. Wind is created by the uneven heating of Earth's surface. Since the Earth is made up of different types of land and water, Earth absorbs the sun's rays at different rates. During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating winds. At night, the winds are reversed because the air cools more rapidly over land than over water. In the same aspect, the larger winds that circle the Earth are created because the land near the equator are heating up more then the land near the Poles. Wind power is the conversion of wind energy into useful sources, such as electricity, using tools such as wind turbines.

Wind turbines are rotating machines that convert the wind into mechanical energy such as electricity. These wind turbines come in two forms, horizontal axis turbines and vertical axis turbines. Horizontal axis turbines have blades like air plane propellers; these are the more common turbines. These blades catch the wind and begin to spin, as they are spinning the generator converts mechanical energy into electricity. A cable in the tower of the turbine carries the electricity to a transmission line. The turbines can move in order to catch the wind drifts by a computer system that is inside the turbine as well. The vertical axis turbines have their rotor shaft vertically set up which is effective because the turbine does not have to be facing the wind. The downfall of these turbines is that they cause some drag and have poor reliability. These turbines are built and used in places called "wind farms" or "wind plants."

Wind plants have dozens of turbines scattered over large areas where electricity tends to be stored and then sold. Wind farms are built in flat, open areas where the wind blows at least 14 miles per hour. Iowa currently has more than 600 wind turbines, producing enough electricity to power 140,000 homes. Minnesota and Wisconsin are also home to wind farms and the number is growing every day. For example, a 1.8 Mega Watt wind turbine at a reasonable site would produce over 4.7 million units of electricity each year, enough to meet the annual needs of over 1,000 households, or to run a computer for over 1,620 years.

There are a handful of inventions that are still in process when dealing with wind power, yet there are many more future ideas that are being looked forward upon. Tom Wind, an electrical engineer in Jefferson, Iowa is planning on building a plant that will store electricity, much like a battery, underground through wind power. Tom Wind is well aware of the fact that wind does not always blow which affects the outlook upon wind plants. People need a steady supply of electricity, not one