How Wind Turbines Work

A wind turbine converts the kinetic energy of moving air into electricity. Wind is simply air in motion, and a mass of air travelling at speed carries energy; the faster the wind, the far greater the energy it carries, since the available power rises steeply with wind speed. A turbine intercepts this flow with its blades, which are shaped so that the passing air makes them turn, capturing part of the wind's energy as rotation.

The turning blades drive a shaft connected, often through a gearbox, to an electrical generator. Inside the generator, mechanical rotation is converted into electric current by the relative motion of magnets and coils of wire. Most large turbines have three blades mounted on a tall tower; height matters because winds are stronger and steadier well above the ground and obstacles. The machine is usually able to swivel so that it faces into the wind, and its blades can be adjusted or the turbine shut down in very strong winds to protect it.

Animations are a useful way to show this chain of energy conversion, because the internal workings are hidden inside the nacelle at the top of the tower. A simulation can illustrate the wind striking the blades, the rotor turning the shaft, the generator producing current, and the way output changes with wind speed. Such visual models also distinguish the common horizontal-axis machines from vertical-axis designs, whose blades spin about an upright shaft.

Frequently asked questions

How does a wind turbine make electricity?

The wind turns the blades, which spin a shaft connected to a generator. The generator converts that rotation into electric current.

Why are wind turbines built on tall towers?

Wind is stronger and steadier higher above the ground, away from obstacles, so a taller tower lets the turbine capture more energy.

Why does wind speed matter so much?

The energy carried by the wind rises steeply with its speed, so even a modest increase in wind speed greatly increases the power a turbine can produce.