Anemometer:
Measures the wind speed and transmits wind speed data to the controller.
Blades:
Lifts and rotates when wind is blown over them, causing the rotor to spin. Most turbines have either two or three blades.
Brake:
Stops the rotor mechanically, electrically, or hydraulically, in emergencies.
Controller:
Starts up the machine at wind speeds of about 8 to 16 miles per hour (mph) and shuts off the machine at about 55 mph. Turbines do not operate at wind speeds above about 55 mph because they may be damaged by the high winds.