INTRODUCTION source Wind is a clean and inexhaustible inexhaustible of energy that can be harnessed harnessed to produce power Historically Historically wind power in the form of windmills has been used for centuries centuries for such tasks as grinding grain and pumping water Today sophisticated wind machines known as wind turbines are used in many parts of the world to convert convert the kinetic energy of wind to electric power Modern commercial wind turbines turbines produce electricity by using rotational energy to drive a generator generator These turbines are made up of a blade or rotor and an enclosure called a nacelle that contains a drive train atop a tall tower Large wind turbines producing up to 1 8 megawatts of power can have a blade length of over 130 feet 40 meters and be placed on towers some 260 feet about 80 m tall Smaller turbines can 4
These wind turbines are part of a wind farm in western Kansas Wind power has a long history and is now of growing importance as an alternative energy source be used to provide power to individual homes Wind farms are areas where a number of wind turbines are grouped together providing a larger total energy source Wind resources are calculated based on the average wind speed and the distribution of wind speed values occurring within a particular area 5
WIND POWER The term windmill which typically refers to the conversion of wind energy into power for milling or pumping is sometimes used to describe a wind turbine 6 hour Areas are grouped into wind power classes that range from 1 to 7 A wind power class of 3 or above equivalent equivalent to a wind power density of 150 to 200 watts per square meter or a mean wind of 11 5 to 12 5 miles per 5 1 5 6 meters per second at a height of 33 feet 10 m above ground is suitable for utility scale wind power generation although some suitable sites may also be found in areas of classes 1 and 2 In the United States there are substantial wind resources in the Great Plains region and in some offshore locations
INTRODUCTION Wind power is an alternative energy source This means that the power of the wind can be used in place of other energy sources such as coal oil and nuclear reactions Fossil fuels such as oil coal and natural gas are available on Earth only in limited supplies and they will run out one day Fossil fuels also add carbon dioxide to the atmosphere when they are burned Scientists believe that this contributes to global warming Burning fossil fuels also adds other pollutants pollutants such as carbon monoxide and nitrogen dioxide to the atmosphere Unlike fossil fuels wind power is a renewable resource that cannot be depleted It also has the added benefit of being virtually pollution-free Challenges to the large-scale implementation of wind energy include siting requirements such as wind availability aesthetic and environmental concerns and land availability Public advocacy groups have raised concerns about the potential disruptions that wind farms may have on wildlife and overall aesthetics aesthetics For example wind generators have been blamed for injuring and killing birds However experts have shown that modern turbines have a small effect on bird populations 7
