How a wind turbine works - over 2 years ago

Wind blows and sets the blades of a turbine in motion, thus generating power (power is derived from the kinetic energy)that can be converted into electricity.
Turbines can be located on land (such as at the Tsitsikamma ECCWEDA farm). They can also be situated in the water, preferably close to the shoreline, where higher wind speeds and more steady wind conditions are available . Wind Speeds are also higher offshore, thus nations are currently striving to invest more in offshore wind plants.

How wind turbines are made

A steel (or concrete) tower is equipped with a kind of machine house (nacelle) on top, which turns around a vertical axis such that the rotor (usually equipped with two or three blades) always faces the wind. Most turbines are manufactured to blend well into the landscape. Most wind turbines have three blades which is a more aesthetically appealing set-up than two-blade turbines. Two-blade turbines are, however, lighter and easier to assemble which makes them preferrable for offshore installations.

Principle on which wind turbines operate

When wind flows, the rotor turns and drives an electric generator. The generation of electric power depends particularly on three factors: wind speed, area of the rotor and air density in the following way:

• cube of wind speed, i.e. double wind speed gives eight times more power
• square of rotor diameter: i.e. double rotor diameter gives four times more power
• density of the air, i.e. the denser the air, the higher the power produced and vice-versa (for example if the air is 10 C colder, density – and power production increase by about 3 %, while moist air, which containing high amounts of water vapour, is less dense and will thus decrease power production).

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