When flowing water is captured and turned into electricity, it is called hydroelectric power or hydropower. Hydropower is the largest source of renewable electricity in the United States, allows the nation to avoid 200 million metric tons of carbon emissions each year, and is responsible for more than 300,000 jobs with the potential to create thousands more.
Hydropower has been using water to make electricity for over a century. Water constantly moves through a vast global cycle, evaporating from lakes and oceans, forming clouds, precipitating as rain or snow, then flowing back down to the ocean. Because the water cycle is an endless, constantly recharging system that is not reduced or used up in the hydropower process, hydropower is considered a renewable energy.
There are several types of hydroelectric facilities, all powered by the kinetic energy of flowing water as it moves downstream. Turbines and generators convert the energy into electricity, which is then fed into the electrical grid to be used in homes, businesses, and by industry. Hydropower facilities provide a number of benefits in addition to producing electricity, such as flood control, irrigation, water supply, and a range of recreational opportunities.
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Types of Hydropower Plants
Explore the three types of hydropower facilities.
Types of Hydropower Turbines
Explore the two types of hydro turbines.
Cutting Edge Hydropower R&D
Explore how the Water Power Program's hydropower research and development (R&D) efforts focus on advancing technologies that produce electricity from elevation differences in falling or flowing water.
Explore how a microhydropower system works.
Explore the three levels of resource assessments performed by the hydropower industry.
Hydropower Use Throughout History
Explore the history of hydropower.
Glossary of Hydropower Terms
Explore the glossary of terms which define the components that make up hydro turbines and hydropower plants.