Wind turbine. (Source: © Grzegorz Targosz / stock.adobe.com)

A device that converts the kinetic energy of the wind into rotational motion by means of drag or lift acting on the turbine blades. The rotating turbine then drives a generator through a gearbox that produces electricity. Horizontal axis turbines are the most commonly used and operate on the principle of lift. There are also less efficient drag turbines, where the wind simply pushes against the blades. Vertical axis turbines are less commonly used, but have the advantage of not having to turn in the direction of the wind and their gearbox and generator are located on the ground.