The Largest Nuclear Power Plants

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By the end of 2012, nuclear power plants were operating in 29 countries. There were 436 reactors in use, and the total installed power output exceeded 374 GW. There were 65 reactors under construction (29 in China, 10 in Russia, and 7 in India) and another 167 on order or planned (51 in China, 24 in Russia, 18 in India, 13 in the USA, 10 in Japan…)

The majority of the energy generated by nuclear power plants was in the USA, which had 104 reactors with a total production of 800 billion kWh. The second is France, with 59 reactors generating 400 billion kWh, and in third place are Russia and Japan.

The majority of the reactors, the so-called 2nd generation reactors, were built in the 1970s. The 3rd generation reactors are now under construction and the 4th generation reactors are under development.

The Largest Nuclear Power Plants around the World

Power plant Power output Country
Kashiwazaki Kariwa 7,965 MWe Japan
Bruce 6,152 MWe Canada
Ulchin 5,881 MWe South Korea
Yeonggwang 5,875 MWe South Korea
Zaporizhzhia Nuclear Power Plant 5,700 MWe Ukraine

In total, the world’s nuclear reactors have served in excess of 15,000 reactor-years.

Kashiwazaki Kariwa

The Japanese power plant Kashiwazaki Kariwa was commissioned in September, 1985. In 1997, it already contained seven reactor blocks with a total installed power output of 7,965 MW making it the largest nuclear power plant in the world. All the reactors are BWR. The power plant generates electricity for 16 million households. It is located in the Niigata prefecture on the coast of the Sea of Japan and the facility is spread over 4.2 km2.


Bruce is the first private nuclear power plant in Canada. Its total area is 9.3 km2 and it is located on the shores of Huron Lake. Bruce A and Bruce B each contain four CANDU reactors for a total installed power output of 6,152 MW. The plant generates electricity for households, schools, and for five hospitals in Ontario. In 2010, the plant celebrated 22 million hours of operation without any serious workplace accident. The first block was commissioned in 1967.


The South Korean power plant Ulchin is located in the province of yongsangbuk. It contains six light-water PWR reactors for a total installed power output of 5,881 MW. The first block was commissioned in 1988 and the last one in 2005. Blocks 3 and 4 were the first Standard Nuclear Plant (KSNP) Korean type reactors and they proved to be both efficient and trouble-free.


The Korean power plant Yeonggwang has the same type of reactors as Ulchin. Construction of the first blocks was started in 1986; the last blocks (5 and 6) were completed in 2002. Blocks 3 and 4 were commissioned in 1996 and 1997 and are classified among the top ten safest operating nuclear reactors in the world. Their total installed power output is 5,875 MW.

Zaporizhzhia Nuclear Power Plant

The Záporožská power station is the largest nuclear power plant not only in the Ukraine, but also in all of Europe. It was built on the shores of the Kakhovka reservoir. Four blocks were commissioned between 1984 and 1987 and another two blocks were commissioned in 1989 and 1995. All the reactors are of the VVER type and the total installed power output is 5,700 MW. The power plant also includes the storage of spent nuclear fuel with sufficient capacity for its entire planned service life. It supplies 20% of the entire power demand of the Ukraine.

Oldbury, located in Great Britain, is the longest operating nuclear power station in the world. It was commissioned in 1967.