Wind energy in environmental engineering free pdf download
Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover.It is a machine composed of 2 or 3 propeller-like blades known as the rotor. The rotor is attached to the top of a tall tower. As the wind blows it spins the rotor. As the rotor spins the energy of the movement of the propellers gives power to a generator. There are a few magnets and a lot of copper wire inside the generator which make electricity.
Because winds are more powerful higher up off the ground, wind turbine towers are about 30 metres tall to allow the rotor to grab more wind energy. The turbines are built with a device that turns the rotor to ensure that it always faces into the wind.
Just one wind turbine can generate enough electricity for a single house or the electrical energy to pump water or to power a mill which grinds grain. The electrical energy can also be stored in batteries.