UNDERSTANDING THE VOCABULARY

1. Kinetic energy vs. potential energy. 

2. Horizontal and vertical axis turbines. Also see Types of Wind Turbines.

3. Nacelle: A nacelle is a cover housing that houses all of the generating components in a wind turbine, including the generator, gearbox, drive train, and brake assembly. See the images below.

4. Tower: The tower of the wind turbine carries the nacelle and the rotor. Towers for large wind turbines may be either tubular steel towers, lattice towers, or concrete towers. See the images below.

5. Inside the wind turbine: Rotor blades, hub, gearbox, generator

6. Shaft: Large three-bladed horizontal-axis wind turbines (HAWT), with the blades upwind of the tower produce the overwhelming majority of windpower in the world today. These turbines have the main rotor shaft and electrical generator at the top of a tower, and must be pointed into the wind. See the image below.

7. Generator: Wind turns the propeller-like blades of a turbine around a rotor, which spins a generator, which creates electricity. See the images below.

8. Anenometer: A wind turbine anemometer is an essential gadget on a wind turbine since it provides accurate measurements of wind and helps to ensure efficiency since wind turbines need to be steered correctly into the wind. See the images below.

9. Up-wind and Down-wind: When wind blows in your face, you are upwind (or going against the direction of the wind). When walking backwards with the wind blowing on your back, you are downwind (going with the direction of the wind). When the wind changes direction, motors turn the nacelle, and the blades along with it, to face into the wind (this movement is called yaw). The blades also 'pitch' or angle to ensure that the optimum amount of power is extracted from the wind. Most wind turbines are upwind turbines.