At present (2026), nuclear power plants are operating in more than 30 countries worldwide. According to the IAEA Power Reactor Information System (PRIS), 417 power reactors are in operation, with a total net installed electrical capacity of approximately 380 GW(e). The operation of a further 21 reactors, with a combined net capacity of about 19 GW(e), is currently suspended. Another 78 reactors, representing more than 81 GW(e) of capacity, are under construction.

The United States remains the world’s largest producer of nuclear-generated electricity, with 94 operating reactors and approximately 785 TWh of nuclear generation in 2025. China ranked second, with 60 reactors and approximately 481 TWh, followed by France (373 TWh), Russia (218 TWh), South Korea (185 TWh) and Japan (93 TWh).

Most reactors operating today belong to Generations II and III, while Generation IV reactor systems remain at the research, development and demonstration stage.

The World’s Largest Nuclear Power Plants by Net Electrical Capacity

The world’s power reactors have accumulated more than 20,800 reactor-years of operating experience since the beginning of commercial nuclear power.

Kashiwazaki-Kariwa

Kashiwazaki-Kariwa Nuclear Power Station was first commissioned in 1985. It comprises seven BWR and ABWR units with a combined net electrical capacity of 7,965 MW(e), making it the world’s largest nuclear power plant by installed capacity. The plant is located in Niigata Prefecture on the coast of the Sea of Japan. Following the Fukushima Daiichi accident, all units were shut down, and their return to operation has been subject to compliance with Japan’s strengthened post-Fukushima safety requirements.

Bruce

Bruce Nuclear Generating Station is Canada’s largest nuclear power plant. Located on the shore of Lake Huron in Ontario, it comprises eight CANDU reactors at the Bruce A and Bruce B stations, with a combined net electrical capacity of approximately 6,478 MW(e). Modernisation and refurbishment programmes have increased the output and extended the operating lives of several units. The first unit entered commercial operation in 1977.

Hanul (formerly Ulchin)

Hanul Nuclear Power Plant, formerly known as Ulchin, is located in Gyeongsangbuk-do Province in South Korea. It comprises six PWR units with a combined net electrical capacity of approximately 5,871 MW(e). The first unit entered commercial operation in 1988 and the sixth in 2005. Units 3 and 4 were the first Korean Standard Nuclear Plant (KSNP) units, an important step in the development of South Korea’s domestic nuclear power programme.

Hanbit (formerly Yeonggwang)

Hanbit Nuclear Power Plant, formerly known as Yeonggwang, is located in South Korea and comprises six PWR units with a combined net electrical capacity of approximately 5,813 MW(e). The first two units entered commercial operation in 1986 and 1987, followed by Units 3 and 4 in 1995 and 1996 and Units 5 and 6 in 2002. Like Hanul, the plant includes Korean Standard Nuclear Plant (KSNP) units developed as part of South Korea’s programme to standardise and localise nuclear power plant technology.

Zaporizhzhia Nuclear Power Plant

Zaporizhzhia Nuclear Power Plant is the largest nuclear power plant in Europe. Located near the city of Enerhodar in southeastern Ukraine, it comprises six VVER-1000 reactors with a combined net electrical capacity of approximately 5,700 MW(e). The units entered commercial operation between 1985 and 1996. The site also includes a dry spent fuel storage facility. Before the war, the plant accounted for a significant share of Ukraine’s electricity generation. Since 2022, its reactors have not been in normal commercial operation.

Nuclear power provides about 9% of global electricity generation and remains the world’s second-largest source of low-carbon electricity after hydropower.