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Water Use FAQs - 9 Found

What is hydroelectric power and how is it used?

Although most energy in the United States is produced by fossil-fuel and nuclear power plants, hydroelectricity is still important to the Nation, as about 7 percent of total power is produced by hydroelectric plants. To create hydroelectric power huge power generators are placed inside dams. Water flowing through the dams spins turbine blades connected to generators. Power is produced and is sent to homes and businesses.
Hydroelectric power has played an important part in the development of this Nation's electric power industry, providing a large portion 40 percent of electricity in America in the early 1900's. (The History of Hydropower Development in the United States) New large-scale hydroelectric facilities will be few and far between in the future as most of the prime locations to place large dams suitable for hydroelectric-power production have already been used. The future of hydroelectric power will be in small-scale and local facilities to provide power to small communities and even individuals.
Hydroelectricity is a form of renewable energy. Other renewable energy resources include geothermal, wave, tidal, wind, and solar power. Hydroelectric powerplants use very few non-renewable natural resources to create electricity, nor do they pollute the air by generating greenhouse gases, as other powerplants may. Water, the "fuel" to run the plant is provided free by nature. 
Reservoirs for dams, however, have a great impact on the local environment and people. Reservoirs may cover people's homes, important natural areas, agricultural land, and archeological sites. Building dams can require relocating people.
Most hydroelectric power plants have structures that may obstruct fish migration and affect their populations. Operating a hydroelectric power plant may also change the water quality, water temperature, and the river's flow. These changes may harm native plants and animals in the river and on land. Methane, a strong greenhouse gas, may also form in some reservoirs and be emitted into the atmosphere.  
In some areas dams are being removed in an effort to address the needs of fish communities and other ecosystem issues.
Learn more: 

Hydroelectric power -- How it works

Hydroelectric power water use

Picture of Hydroelectric Generators

Dam removal on the Elwha River in Washington

Tags: Ecosystems, Energy, Water, Steam, Power