The simplest way to think about this is to imagine that a wind turbine works in exactly the opposite way to a fan. Instead of using electricity to make wind, like a fan, turbines use the wind to make electricity.
Almost all wind turbines producing electricity consist of rotor blades, which rotate around a horizontal hub. The hub is connected to a gearbox and generator, which are located inside the nacelle. The nacelle is the large part at the top of the tower where all the electrical components are located.
Most wind turbines have three blades, which face into the wind; the wind turns the blades round, this spins the shaft, which connects to a generator and this is where the electricity is made. A generator is a machine that produces electrical energy from mechanical energy, as opposed to an electric motor, which does the opposite!
What they are made of.
The towers are mostly tubular and made of steel, generally painted light grey. Some towers are made of concrete. The blades are made of glass-fibre reinforced polyester or wood-epoxy. They are light grey because this is the colour which is most inconspicuous under most lighting conditions. The finish is matt, to reduce reflected light.
Wind turbines are not noisy. It is possible to stand underneath a turbine and hold a conversation without having to raise your voice. As wind speed rises, the noise of the wind masks the noise made by wind turbines. Wind farming is popular with farmers, because their land can continue to be used for growing crops or grazing livestock. Wind turbines do not disturb sheep, cows and horses.
Popularity of wind energy.
Wind energy is one of the most popular energy technologies. Opinion surveys regularly show that just over eight out of ten people are in favour of wind energy, and less than one in ten (around 5%) are against it. The rest are undecided.
Size of a wind turbine.
Large modern wind turbines have rotor diameters ranging up to 65 meters while smaller machines (around 30 meters) are typical in developing countries. Towers range from 25 to 80 meters in height.
How a wind turbine works.
Wind turbines start operating at wind speeds of 4 to 5 metres per second (around 10 miles an hour) and reach maximum power output at around 15 meters/second (around 33 miles per hour). At very high wind speeds, i.e. gale force winds, (25 metres/second, 50+ miles/hour) wind turbines shut down.
The amount of electricity one wind turbine produces.
One 600kW wind turbine at a reasonable site would produce enough electricity to meet the annual needs of 375 households
Life span of wind turbines.
A wind turbine typically lasts around 20-25 years. During this time, as with a car, some parts may need replacing.
Cost to make electricity from the wind.
Wind energy is one of the cheapest of the renewable technologies. It is competitive with new clean coal fired power stations and cheaper than nuclear power. The cost of wind energy varies according to many factors. An average for a new wind farm in a good location is 2.88 pence per unit, which compares favourably with the current
price of around 2.4 pence.
More Information on Wind Power