The nacelle..

is located at the top of the tower and houses the mechanical machinery such as the generator and gearbox. The rotor transforms the energy from the wind into rotational energy. Most modern wind turbine rotors consist of three turbine blades attached to a hub, although two bladed and one bladed turbines can also be found. Modern commercial wind turbine blades range from 30 to 70 metres in length and are generally made of glass-fiber reinforced polyester or wood-epoxy. A modern commercial wind turbine rotor is likely to have a rotational speed of between 15 to 30 rpm.

How Wind Turbines Work

The energy of motion is known as "kinetic energy". Wind turbines work by turning the kinetic energy in the wind into electricity.