Largest Hydroelectric Power Stations in the World (2025)

Data

Note: How Hydroelectric Power Stations Work

What "installed capacity" actually measures

Every number in the chart above is an installed (nameplate) capacity in megawatts (MW). One gigawatt (GW) equals 1,000 MW. Capacity is the maximum output a plant can reach when its turbines are all spinning at full design load, not the amount of electricity it actually produces in a year.

Real output depends on how much water is flowing and how high it falls. That difference is why the table's second number, annual output in terawatt-hours (TWh), does not track capacity in a straight line. Itaipu, at 14,000 MW, has generated a world record of roughly 103 TWh in a single year because the Paraná river's flow is remarkably steady, giving it a capacity factor above 80%. Three Gorges has 22,500 MW but has peaked near 112 TWh because its river flow varies through the year, so its average output sits closer to 55 to 60% of nameplate. In short: capacity shows how big a plant is, output shows how hard it actually works.

Why China dominates the list

• China holds 8 of the top 20 stations, including the top two: Three Gorges (22,500 MW) and Baihetan (16,000 MW).
• The country's entire hydropower fleet is the largest on Earth, well past 400 GW, and China accounted for roughly three-quarters of global hydropower capacity additions in recent years.
• Most of the giant dams sit in the mountainous southwest on the Jinsha river cascade (Baihetan, Xiluodu, Wudongde, Xiangjiaba), where steep gorges provide enormous head, the vertical drop that drives a turbine.
• Brazil (Belo Monte, Tucuruí) and Russia (Sayano-Shushenskaya, Krasnoyarsk, Bratsk) are the other repeat names, followed by Canada, Venezuela, Ethiopia, Pakistan and the United States.

Three kinds of hydro plant, one ranking

• Reservoir (impoundment) plants: a dam holds back a large lake, so the plant can store water and generate on demand. Three Gorges, Itaipu, Grand Coulee and Guri are all in this category, which is why they are the biggest.
• Run-of-river plants: little or no storage, power comes from the river's natural flow. Belo Monte is the great example, designed with a reduced reservoir to limit flooding in the Amazon.
• Pumped storage: water is pumped uphill when electricity is cheap and released downhill when demand spikes. Plants like China's Fengning (3,600 MW) are net consumers of electricity, not net producers, so they sit outside this table even though their numbers look huge.
• Because of that distinction, only seven facilities in the world exceed 10,000 MW, and this chart contains exactly those seven at the top.

The engineering inside

• Water is carried down through penstocks, giant pipes that convert the reservoir's stored potential energy into fast-moving flow, which then spins a turbine coupled to a generator.
• Three turbine families cover almost everything: Francis turbines for medium heads (the vast majority of big dams), Kaplan turbines for low heads and high flows, and Pelton wheels for very high heads.
• Modern hydro turbines convert about 90% of the available water energy into rotation, which is why hydro is one of the most efficient ways humans make electricity.
• Three Gorges is powered by 32 main units of 700 MW plus two smaller 50 MW units. Itaipu uses 20 units of 700 MW.

Records and moments that shaped the list

• The title of "largest hydro station" has passed hands three times: Hoover Dam (1,345 MW, 1936), then Grand Coulee Dam (6,809 MW, 1942), then Itaipu (14 GW, 1984), and finally Three Gorges (22.5 GW) from 2008 onward.
• Grand Coulee's wartime output fed aluminium smelters that built aircraft for the Second World War, and it is still the largest power plant of any kind in the United States.
• Itaipu is a genuinely binational plant: the dam sits on the Brazil-Paraguay border and the two countries share its output. It supplies the large majority of Paraguay's electricity.
• The Grand Ethiopian Renaissance Dam (5,150 MW) on the Blue Nile became Africa's largest hydropower plant, with full commissioning completed in the mid-2020s.
• Russia's Sayano-Shushenskaya plant suffered a catastrophic turbine failure in 2009 that killed 75 workers; the station was rebuilt and fully restored by 2014.

Why hydropower still matters globally

Hydropower produces roughly 15% of the world's electricity (about 4,210 TWh in 2023), more than all other renewable sources combined and more than nuclear power. Global installed hydropower capacity passed 1,456 GW in 2025, the largest of any renewable technology. Its key advantage is dispatchability: unlike wind and solar, a reservoir plant can be ramped up in seconds to cover evening peaks, which makes it a backbone of grid stability in countries such as Brazil, Norway, Canada, Switzerland and China. Pumped storage, a close cousin of conventional hydro, provides around 85% of the world's grid-scale energy storage.

Trade-offs worth knowing

• Displacement: reservoirs flood valleys. Three Gorges resettled well over a million people, one of the largest planned relocations in history.
• Ecosystems: Belo Monte's diversion reduced flow in the Volta Grande stretch of the Xingu, hitting Indigenous communities and fisheries that depend on the river.
• Methane: in tropical regions, vegetation rotting under warm reservoir water can release methane, trimming hydro's climate advantage over fossil fuels.
• Sediment and fish: dams trap silt that would otherwise rebuild deltas, and they block migratory fish unless fish ladders or transport systems are built.
• Drought risk: a dry year hits output hard. Low reservoir levels have cut generation at Venezuela's Guri and Brazil's Tucuruí in recent droughts.
• Storage bonus: the IEA estimates that the reservoirs of existing conventional plants together can store about 1,500 TWh of electrical energy in one full cycle, roughly 170 times more than the entire global pumped-storage fleet.

Fun facts

• The first hydroelectric central station began operating in 1882 in Appleton, Wisconsin, making hydro the oldest large-scale renewable electricity technology.
• Three Gorges also includes a ship lift that raises vessels up to 3,000 tonnes through a lift of about 113 metres, so river traffic can pass the dam.
• Norway generates close to 90% of its electricity from hydropower, and Brazil around 60%, which is why both countries barely notice oil price swings in their power bills.
• Hydro plants last a very long time. Grand Coulee has been generating since 1942 on the same river, and many stations in Europe and North America are a century old.
• Because a reservoir can hold water for months, a single large dam behaves like a giant battery, storing summer rain and spending it in winter.