Wind power works by harnessing the breeze that passes over the rotor blades of a wind turbine and rotates a hub. The hub is connected to a gearbox via a low-speed shaft and a high-speed shaft that drive a generator contained within a nacelle. The generator converts the energy into electricity.
A typical wind turbine is a sleek, slender structure that consists of a three-bladed rotor that extends up to 235 feet in diameter attached to the top of a tall tower that can range in height from 132 to 256 feet. A yaw mechanism uses electrical motors to turn the nacelle with the rotor against the wind. An electronic controller senses the wind direction using a wind vane. The devices make a whooshing noise that registers an average of 45 decibels. The average output per turbine ranges from 500 to 1,500 kilowatts.