A wind turbine is made up of two or three propeller-like blades called 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 some magnets and a lot of copper wire inside the generator that make electricity.
Winds are stronger higher up off the ground, so wind turbine towers are about 30 metres tall to allow the rotor to catch more wind energy. The turbines are built with a device that turns the rotor so 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.
Wind farms are places where many wind turbines are clustered together. They are built in places where it is nearly always windy. The electricity that is generated at a wind farm is sold to electricity companies that provide the electricity to people living in cities and towns.
What are the advantages of wind turbines?
They are pollution free.
The energy they generate is renewable. This means that as long as the winds blow there is power to turn the blades of the rotor. (Another form of renewable energy comes from the Sun. Energy from the Sun is called solar energy)
Using wind energy means that less fossil fuel (coal and oil) needs to be burned to make electricity. Burning fossil fuel pollutes the atmosphere and adds greenhouse gases to it. This pollution is a cause of global warming.
What are the disadvantages of wind turbines?
Some people don’t like the look of the turbines. They say that they spoil the look of the natural environment.
Wind turbines make some noise.
Turbines kill birds that fly into them. However collisions are rare and there are reports from Denmark saying that some falcons had built nests on the top of turbine towers. To protect birds however, it is important that wind farms be built away from bird sanctuaries and from the pathways of migratory birds. (Migratory birds are those that fly from cold places in winter to warmer parts of the world)