Thứ Tư, 10 tháng 7, 2013

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When Bob Dylan first sang Blowin’ in the Wind in the early 1960s, he probably wasn’t talking about wind power as the answer to the world’s ever-increasing need for electricity and sources of clean, renewable energy. But that is what wind has come to represent for millions of people, who see wind power as a better way to generate electricity than plants fueled by coal, hydro (water) or nuclear power. 
Wind Power starts with the Sun
Wind power is actually a form of solar power, because wind is caused by heat from the sun. Solar radiation heats every part of the Earth’s surface, but not evenly or at the same speed. Different surfaces—sand, water, stone and various types of soil—absorb, retain, reflect and release heat at different rates, and the Earth generally gets warmer during daylight hours and cooler at night. 
As a result, the air above the Earth’s surface also warms and cools at different rates. Hot air rises, reducing the atmospheric pressure near the Earth’s surface, which draws in cooler air to replace it. That movement of air is what we call wind. 
Wind Power is Versatile
When air moves, causing wind, it has kinetic energy—the energy created whenever mass is in motion. With the right technology, the wind’s kinetic energy can be captured and converted to other forms of energy such as electricity or mechanical power. That’s wind power. 
Just as the earliest windmills in Persia, China and Europe used wind power to pump water or grind grain, today’s utility-connected wind turbines and multi-turbine wind farms use wind power to generate clean, renewable energy to power homes and businesses. 
Wind Power is Clean and Renewable
Wind power should be considered an important component of any long-term energy strategy, because wind power generation uses a natural and virtually inexhaustible source of power—the wind—to produce electricity. That is a stark contrast to traditional power plants that rely on fossil fuels. 
And wind power generation is clean; it doesn’t cause air, soil or water pollution. That’s an important difference between wind power and some other renewable energy sources, such as nuclear power, which produces a vast amount of hard-to-manage waste. 
Wind Power Sometimes Conflicts with Other Priorities
One obstacle to increasing worldwide use of wind power is that wind farms must be located on large tracts of land or along coastlines to capture the greatest wind movement.
Devoting those areas to wind power generation sometimes conflicts with other priorities, such as agriculture, urban development, or waterfront views from expensive homes in prime locations. 
The Future Growth of Wind Power
As the need for clean, renewable energy increases, and the world more urgently seeks alternatives to finite supplies of oil, coal and natural gas, priorities will change. 
And as the cost of wind power continues to decline, due to technology improvements and better generation techniques, wind power will become increasingly feasible as a major source of electricity and mechanical power. 






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