For any wind turbine, the power
and energy output increases
dramatically as the wind speed
Therefore, the most cost-effective
wind turbines are located in the
windiest areas. Wind speed is
affected by the local terrain and
increases with height above the
ground, so wind turbines are
usually mounted on tall towers.Wind energy is the kinetic
energy that is present in movingair : this kinetic energy in turn
derives from the heating of theatmosphere, earth, and oceans
slightly by the density of the air,which is determined by the air
temperature, barometricpressure, and altitude.
For any wind turbine, the power
and energy output increases
dramatically as the wind speed
Therefore, the most cost-effective
wind turbines are located in the
windiest areas. Wind speed is
affected by the local terrain and
increases with height above the
ground, so wind turbines are
usually mounted on tall towers
Worldwide development of wind energy expanded rapidlystarting in the early 1990s. In 1999, over $3.5B was invested infarms that use wind energy. Most of the investment was
spent in Europe where conventional electricity costs are higherand where political motivation to reduce greenhouse gaspollution is greater. At the end of April 1999, 10,000
megawatts of wind-generated electricity produced some 22.5TWh of electricity. That is sufficient electricity for all theindustrial, commercial and domestic electrical
requirements of about two cities the size of Madrid, Spain – atotal of about 8 million people.
Wind energy is an ideal renewable energy because: • it is a pollution-free,infinitely sustainable form of energy• it doesn't require fuel• it doesn't create greenhouse gases• it doesn't produce toxic or radioactive waste Wind energy is quiet and doesn't
present any significant hazard to birds or other wildlife. When large arrays of windturbines are installed on farmland, only about 2% of the land area is requiredfor
the wind turbines. The rest is available for farming, livestock, and other uses.
Landowners often receive payment for the use of theirland, which enhances their income and increases thevalue of the land. Ownership of wind turbinegenerators
by individuals and the community allows people toparticipate directly in the preservation of ourenvironment.Each megawatt-hour of electricity that is generated bywind energy helps to reduce the 0.8 to 0.9 tonnes ofgreenhouse gas emissions that are produced by coal ordiesel fuel generation each year.
We have been harnessing the wind's energy forhundreds of years. From old Holland to farms in theUnited States, windmills have been used for pumpingwater or grinding grain. Today, the windmill's modernequivalent—a wind turbine—can use the wind's energyto generate electricity.
Wind turbines, like windmills, are mounted on a towerto capture the most energy. At 100 feet (30 meters) ormore aboveground, they can take advantage of thefaster and less turbulent wind. Turbines catch thewind's energy with their propeller-like blades. Usually,two or three blades are mounted on a shaft to form arotor.
A blade acts much like an airplane wing. When thewind blows, a pocket of low-pressure air forms on thedownwind side of the blade. The low-pressure airpocket then pulls the blade toward it, causing the rotorto turn. This is called lift. The force of the lift isactually much stronger than the wind's force againstthe front side of the blade, which is called drag. Thecombination of lift and drag causes the rotor to spinlike a propeller, and the turning shaft spins a generatorto make electricity.
This is a webpage just for explaining the wind energy
