Wind Energy
How Wind Energy is Formed and Used
Wind turbines convert kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity. A typical horizontal wind machine is as tall as a 20-story building. Wind machines need to be very tall to capture enough wind to generate large amounts of electricity. An average wind speed of only 14 miles (22.5 kilometers) per hour is needed to convert wind energy into electricity.
Wind power plants create little disruption to local ecosystems. Utility-scale wind power plants built on open terrain require about 60 acres per megawatt of installed capacity. But, according to the American Wind Energy Association, only about 5% of this area is needed for the actual turbines and other equipment. The rest of the land can be used for other purposes like farming and ranching.
Wind energy is gaining popularity around the world. Scotland, for example, is home to the United Kingdom’s largest wind farm, in addition to two huge offshore wind turbines and several other onshore wind farms. Scotland’s windy climate makes it the perfect spot for successful wind turbines. Scotland’s government wants to generate 31% of its electricity from renewable energy by 2011, with much of that coming from wind power.
And in China, which has a vast amount of land and a long coastline, wind power has great potential to generate power for the country’s large population. Around 80 wind farms are currently operating in China, and more than a dozen Chinese companies are building wind turbines and their accompanying components. But the country is experiencing some problems with wind power, because not all of its current wind power capacity is connected to its power grids, meaning some wind power (about 28%, according to China Power Union) is lost.
Wind power has a high initial cost – building the turbines, towers and foundations is expensive.
However, wind energy is becoming more affordable as technology improves. According to RenewableUK, world wind energy capacity doubled every three years between 1990 and 2002, and with each doubling, prices fell by 15%.
Some critics of wind energy say that wind turbines are unsightly. Industry professionals work to minimize this issue by using computer simulations to evaluate the visual impact before construction beings and by using turbines that are the same size and spacing them out evenly once the project is approved.
