Share this
by Career Guide on Jun 13, 2023 12:34:22 PM
The best hydro sites around the world have been dammed to provide the water to power electricity-generating turbines. Find out more about these clean-power giants.
By Jeffrey Winters
Hydropower is one of the oldest forms of renewable energy. Even before the discovery of electricity, humans were using the force of running water to turn wheels for powering grain mills or even factories. Beginning in the 20th century, though, the best hydro sites have been dammed to provide the water to power electricity-generating turbines.
Hydropower generates electricity on every continent except Antarctica. Though environmentalists criticize many projects for their detrimental impact on fish and other river creatures, the largest hydroelectric dams can transform regions or entire countries by providing gigawatts of dependable electricity. Here’s a list of the largest hydroelectric dams on each continent.
Australia: Tumut 3 Power Station
Photo by Colin Henein
Due to its status as the driest continent, there are few watersheds in Australia with the potential for hydropower. The Tumut 3 Power Station, located on the Snowy River in southeastern Australia, is rated at 1,600 MW and is the largest single provider of hydroelectricity in the country. Completed in 1973, it’s part of a larger power and irrigation scheme that provides water to the parched region to the west of the Great Dividing Range while providing as much as 3.7 GW of power.
Africa: Aswan High Dam
Photo by Olaf Tausch
Since ancient times, annual flooding on the Nile River was a blessing, providing water and vital nutrients to farmland along its banks, and a potential curse if flood levels got too high. When it was conceived in the 1950s, the Aswan High Dam was designed to control the annual flood and provide as much as 2,100 MW of electricity to help modernize Egypt. Designed by Soviet engineers and completed in 1970, the dam is not only the largest provider of hydroelectricity in Africa, but it is also the world’s largest embankment dam. The Grand Ethiopian Renaissance Dam, which is filling now, will have a capacity of more than 5,000 MW.
Europe: Volga Hydroelectric Station
Photo by Anna Novikova
Russia has many exceptionally large hydroelectric power stations, but the largest are in the Siberian portion of the country. The Volga Hydroelectric Station is located in the European portion of Russia, along its famed Volga River. When it was completed in 1961, it was not only the largest hydropower project in Europe, a title it still holds, but with a maximum capacity of 2,700 MW it was the largest power station in the world. The power plant is connected to the only high voltage DC line in Russia to send electricity east.
North America: Grand Coulee Dam
Photo by United States Bureau of Reclamation
Started during the Great Depression, this dam on the Columbia River was a way to provide economic benefit to the dry eastern region of Washington state. Irrigation from the dam helped farmers there become more productive, but the electricity had a wider impact. Not only did the abundant power from dam help spur the aluminum and aerospace industry in the Pacific Northwest, but electricity from the dam (completed in 1942) was used by the nearby Hanford site to produce plutonium for some of the first nuclear weapons. After expansion in the 1970s, the dam can generate more than 7,000 MW.
South America: Itaipu Dam
Photo by NASA
The Itaipu Dam spans the Paraná River between Paraguay and Brazil. The structure is actually four dams joined together, and engineers used enough steel during construction to build 380 Eiffel Towers. The two countries split the output of the 14,000 MW of the dam’s 20 turbines, but Paraguay gets more power than it can use and sells the excess back to Brazil. It was the largest hydropower facility for nearly 30 years after its completion date in 1984.
Asia: Three Gorges Dam
Photo by Rehman
Engineers have long considered the site along the Yangtze River in China as a prime spot for a hydroelectric dam. As completed, the Three Gorges Dam can hold back a wall of water more than 360 feet high. Its construction and the filling of the reservoir was controversial for its ecological and human impact; in total, its construction relocated more than 1 million residents. But since engineers completed the dam in 2012, its 32 turbines have a total installed capacity of 22,500 MW, which is power that the country’s coal power plants would generate. Three Gorges Dam should hold the record as the largest hydroelectric dam for some time, as there are no plans currently to build anything larger.
Jeffrey Winters is editor in chief of Mechanical Engineering magazine.
Putting Hydrogen to the Economic Test
On Track to a Hydrogen-Powered Locomotive