Hydro energy is the energy inherent to moving water. More specifically, hydro energy or hydropower is used in the context of electricity generated from water. In the simplest terms, dams are built and river water is stored behind the retaining wall. The potential energy of the stored water is converted to electricity by the fall of water streams on the turbines, which in turn rotate the generators. Hydroelectricity is a major source of electricity around the world and its contribution is only dwarfed by thermal power plants (that run on fossil fuels, such as coal and natural gas). Hydropower is a cleaner source of electricity generation, in comparison to thermal power plants, and does not produce any carbon dioxide emissions, thus protecting the environment. Hydropower projects are large scale projects and may require rehabilitation of people and animals and have some environmental concerns.
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