How Much Energy Does a WindTurbine Generate?

A typical modern wind turbinehas a capacity of two megawatts (MW). A single turbine with this capacity isexpected to generate the same amount of electricity as used by 1118 averagehouseholds.

Low-speed shaft The rotor turns the low-speed shaft rotates at between15 to 30 rpm.

The gearbox increases the rotational speed of the low speed shaft(15 to 30 rpm) and delivers it to the high speed shaft(1000 – 3000 rpm) which drives the generator. Some modern wind turbineshave a ‘direct drive’ generator instead of a gearbox.

High-speed shaft Drives the generator and rotates at between 1000 and3000 rpm.

The generator uses magnetic fields to convert the resultantrotational energy into electrical energy.

The anemometer and wind vaneare both located on the back of thenacelle and monitor wind direction and wind speed. The information gathered isused by the wind turbine control systems to ensure that the wind turbine isfacing into the wind and generating the maximum amount of energy. The windspeed data is also used to monitor performance and let the operating systemknow when to start and shut down the turbine. A modern wind turbine startsgenerating energy at wind speeds of about 4 to 5 m/s (9 to 11 mph) and shutsdown at about 25 m/s (56 mph).

The yaw mechanism turns the nacelle and rotor towards the prevailingwind

Tower: Most modern turbines are made out of tubular steel althoughlattice towers are still used in some countries. Towers for modern commercialturbines range in height from 60 meters to 100 meters.

The transformer converts voltage to that required for the electricitynetwork. The transformer can be within the tower or located outside at the baseof the tower.

 

For further information on howa wind turbine works you can view the relevant sections from the British Wind Energy Association (BWEA), the DanishWind Industry Association or the US Department of Energy. Alternatively you can view the Companion Guide to Planning PolicyStatement 22 (page 155 to 165) producedby the Office of the Deputy Prime Minister.