How Wind Turbines Work
Wind turbines capture the wind's energy with two or three propeller-like blades, which are mounted on a rotor, to generate electricity. The turbines sit high atop towers, taking advantage of the stronger and less turbulent wind at 100 feet (30 meters) or more above ground.
A blade acts much like an airplane wing:
- When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade.
- The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift.
- The force of the lift is actually much stronger than the wind's force against the front side of the blade, which is called drag.
- The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.
Overall, the wind energy centers works like this:
| Stage |
Description |
| 1 |
A computer automatically controls each turbine. |
| 2 |
The computer turns the rotor consisting of three blades and a hub inside a nacelle (enclosure) to face into the wind. |
| 3 |
The rotor turns (depending on the type of wind turbine) at 11-22 rotations per minute. As the wind blows, the pitch of the rotor blade adjusts to suit the changes in the wind speed. For safely purposes, the turbine shuts down automatically if the wind speed exceeds 56 miles per hour. |
| 4 |
The blades drive the main shaft, which drives the generator through a gearbox to convert the mechanical power to electrical power. |
| 5 |
The electricity is cabled down the turbine tower, then through a series of transformers and underground distribution lines before entering the main substation. |
| 6 |
At the substation, the voltage is stepped up and delivered to the electric grid. The stepup enhances the efficiency of energy transmission to homes and businesses. |
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