Describe the process of electricity generated by wind energy?

Difficulty: Medium

Wind energy:

              The wind has been used as a source of energy for centuries. It has powered sailing ships across the oceans. It has been used by windmills to grind grain and pump water.

              More recently, wind power is used to turn wind turbines. When many wind machines are grouped on wind farms, they can generate enough power to operate a power plant.

In the United States, some wind farms generate more than 1300 MW of electricity a day.