Hydropower

Flowing water creates energy that is captured and turned into electricity. This is called hydropower. Hydropower is currently the largest source of renewable power, generating nearly 10 percent of the electricity used in the United States.

The most common type of hydropower plant uses a dam on a river to store water in a reservoir. Water released from the reservoir flows through a turbine, spinning it and then activates a generator to produce electricity.

Types of hydropower plants

But hydropower doesn't necessarily require a large dam. Some hydropower plants just use a small canal to channel the river water through a turbine. Another type of hydropower plant—called a pumped storage plant—can even store power. The power is sent from a power grid into the electric generators. The generators then spin the turbines backward, which causes the turbines to pump water from a river or lower reservoir to an upper reservoir, where the power is stored. To use the power, the water is released from the upper reservoir back down into the river or lower reservoir. This spins the turbines forward, activating the generators to produce electricity.

A renewable energy source

Hydropower is an emissions-free, renewable and reliable energy source that serves our nations environmental and energy policy objectives. With zero air-emissions, hydropower helps in the fight for cleaner air. Hydropower's fuel—water—is essentially infinite and is not depleted in the production of energy. This helps to preserve our nation's independence from supply disruptions overseas. And, as a source of energy, hydropower excels at preserving the stability and reliability of the electrical grid due to its unique operating characteristics. Since 1880, when 16 brush-arc lamps were powered using a water turbine at the Wolverine Chair Factory in Grand Rapids, Mich., hydropower has played a vital role in the U.S. energy mix.

For more information on hydropower, see the below web links.

Foundation for Water and Energy

Hydro Power Research Foundation

Hydropower Program

Low Impact Hydro Institute

National Hydropower Association