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Hydropower is now used principally for hydroelectric power generation, and is also applied as one half of an energy storage system known as pumped-storage hydroelectricity. Hydropower is an attractive alternative to fossil fuels as it does not directly produce carbon dioxide or other atmospheric pollutants and it provides a relatively ...
Hydroelectric projects can be disruptive to surrounding aquatic ecosystems both upstream and downstream of the plant site. Generation of hydroelectric power changes the downstream river environment. Water exiting a turbine usually contains very little suspended sediment, which can lead to scouring of river beds and loss of riverbanks. [48]
Kaplan turbine and electrical generator cut-away view. The runner of the small water turbine. A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work. Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now, they are ...
The pump-turbine units were uprated in July 1972 from their initial rating of 175 MW each to 204 MW each, increasing the plant's overall rating from 350 MW to 408 MW. [3] [16] From 1998–1999, the turbine runners for both units were upgraded, resulting in improved flow rates and another power uprate to 225 MW per unit (450 MW total). [17] [16]
Most current hydroelectric projects use a large hydraulic head to power turbines to generate electricity. The hydraulic head either occurs naturally, such as a waterfall, or is created by constructing a dam in a river valley, creating a reservoir. Using a controlled release of water from the reservoir drives the turbines.
The following page lists hydroelectric power stations that generate power using the run-of-the-river method. This list includes most power stations that are larger than 100 MW in maximum net capacity, which are currently operational or under construction.
The Hoover Dam in Arizona and Nevada was the first hydroelectric power station in the United States to have a capacity of at least 1,000 MW upon completion in 1936. Since then numerous other hydroelectric power stations have surpassed the 1,000 MW threshold, most often through the expansion of existing hydroelectric facilities.
The project began to take shape in the late 1950s, with the planning and construction of the Kelsey dam and hydroelectric power station, and later was expanded to include the diversion of the upper Churchill River into the Nelson River and the transformation of Lake Winnipeg, the world's 11th largest freshwater lake, into a hydroelectric ...