James Madison University

How Does A Wind Turbine Work?

Electricity Generation

Wind power is the conversion of kinetic energy in the wind to electrical energy.

  1. The wind turns the blades which are attached to a rotor.
  2. The rotor spins creating mechanical energy.
  3. The shaft turns a generator which creates electricity.
  4. The electricity is then added to the grid.

In order to generate electricity, two things are needed:

  1. Conductor – commonly copper wire
  2. Magnetic field – electromagnets

The flow of electrons could occur in one of two ways:

  1. Conductor rotates through a magnetic field, or
  2. Magnets move back and forth through a looped wire.
The flow of electrons during electricity generation. The flow of electrons during electricity generation.

Parts of a Wind Turbine

The parts of a wind turbine.

These are the main components of large utility-scale turbines. However, most residential-scale turbines do not have pitching blades, yaw drives, or controllers. The smaller turbines have stationary blades and utilize passive yaw control sometimes with a tail or through a downwind design (blades are downwind of the tower). Not all turbines have a gearbox, many manufacturers are eliminating this component and focusing on direct drive systems to increase efficiency and decrease maintenance costs. The Department of Energy has a great video showing how large scale wind turbines work. They have also published a tool that shows how distributed (residential and community-scale) turbines work.

Blade Design

Wind turbine blade design

Wind turbine blades work on the principle of lift – like an airplane. As the wind passes over the blade, high and low pressure systems are formed due to differences in the speed of the wind passing over the blade. This creates lift and causes the blades to rotate. HowStuffWorks.com has a good tutorial covering wind turbine aerodynamics and the lift principle.

Blade Characteristics

  • Length
  • Width
  • Shape
  • Weight
  • Material
  • Pitch
  • Number
  • Distance from hub
  • Others

The Department of Energy has more detailed lessons on how wind turbines work.