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| Global ranking of the world's largest operating nuclear power plants by net electrical capacity (MWe). |
Nuclear power plays an important role in providing reliable, large-scale electricity around the world. As one of the major clean energy sources, nuclear power can provide low-carbon electricity at a large scale. Some of the world’s largest nuclear power plants bring several reactors together at a single site, allowing them to generate thousands of megawatts of electricity for national and regional power grids.
For this ranking, plant size is measured by net electrical capacity (MWe), which represents the electricity available for delivery to the grid after the plant’s own electricity requirements are accounted for. This provides a more useful basis for comparing the actual generating capacity of different nuclear power plants.
This guide presents the top 20 largest nuclear power plants in the world, ranked by the net capacity of their currently operable reactors. For each plant, you will find its country, reactor fleet, capacity, and current operational status.
How Are the Largest Nuclear Power Plants Ranked?
The facilities in this ranking are evaluated by their combined net electrical capacity, measured in megawatts electric (MWe). When a nuclear power plant has multiple reactors at the same site, the net capacity of its currently operable reactors is combined to determine its total capacity.
This ranking follows three main criteria:
- Operable Capacity Only: The ranking includes the net capacity of currently operable reactors. Reactors under construction, permanently shut down, or decommissioned are excluded from the ranked capacity.
- Plant Site or Complex, Not Individual Reactor: The ranking considers the combined capacity of reactors operating at the same nuclear power plant site or complex. This means a multi-reactor site or complex can rank higher than a site with a single high-capacity reactor.
- Reference Data: Capacity and reactor-status information are based primarily on the International Atomic Energy Agency Power Reactor Information System (IAEA PRIS) and cross-checked with the World Nuclear Association (WNA) Reactor Database. Reactor capacity and status can change over time, so the figures represent the latest available data used for this ranking.
Understanding MWe and MWt
Nuclear power plants are commonly described using two different capacity measurements:
- MWt (megawatts thermal): The amount of thermal energy produced by the reactor.
- MWe (megawatts electric): The electrical generating capacity of the reactor or power plant.
Thermal energy is converted into electricity through the plant's steam turbine and generator. Because only part of the reactor's thermal energy can be converted into electricity, the MWe rating is considerably lower than the MWt rating.
Top 20 Largest Nuclear Power Plants in the World
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| Comparison chart showing operable net electrical capacity (MWe) across leading nuclear generating sites. |
| Rank | Nuclear Power Plant | Country | Net Capacity (MWe) | Operable Reactors | Status |
|---|---|---|---|---|---|
| 01 | Bruce Nuclear Generating Station | Canada | 6,478 | 8 | Operable |
| 02 | Hongyanhe Nuclear Power Plant | China | 6,366 | 6 | Operable |
| 03 | Tianwan Nuclear Power Plant | China | 6,240 | 6 | Operable |
| 04 | Qinshan Nuclear Power Complex | China | 6,196 | 9 | Operable |
| 05 | Fuqing Nuclear Power Plant | China | 6,150 | 6 | Operable |
| 06 | Yangjiang Nuclear Power Plant | China | 6,000 | 6 | Operable |
| 07 | Hanul Nuclear Power Plant | South Korea | 5,871 | 6 | Operable |
| 08 | Hanbit Nuclear Power Plant | South Korea | 5,813 | 6 | Operable |
| 09 | Gravelines Nuclear Power Plant | France | 5,460 | 6 | Operable |
| 10 | Barakah Nuclear Energy Plant | United Arab Emirates | 5,348 | 4 | Operable |
| 11 | Paluel Nuclear Power Plant | France | 5,320 | 4 | Operable |
| 12 | Cattenom Nuclear Power Plant | France | 5,200 | 4 | Operable |
| 13 | Kori Nuclear Power Complex | South Korea | 4,605 | 5 | Operable |
| 14 | Fangchenggang Nuclear Power Plant | China | 4,210 | 4 | Operable |
| 15 | Ningde Nuclear Power Plant | China | 4,072 | 4 | Operable |
| 16 | Palo Verde Generating Station | United States | 3,937 | 3 | Operable |
| 17 | Olkiluoto Nuclear Power Plant | Finland | 3,355 | 3 | Operable |
| 18 | Taishan Nuclear Power Plant | China | 3,320 | 2 | Operable |
| 19 | Shidaowan Guohe One Nuclear Power Plant | China | 2,838 | 2 | Operable |
| 20 | Saeul Nuclear Power Plant | South Korea | 2,784 | 2 | Operable |
1. Bruce Nuclear Generating Station - Canada
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| Bruce Nuclear Generating Station in Ontario, Canada - the world's largest operating nuclear power plant by combined net capacity (6,478 MWe). |
Key Facts
- Country: Canada
- Location: Tiverton, Ontario, on the shore of Lake Huron
- Net Capacity: 6,478 MWe
- Operable Reactors: 8
- Reactor Type: PHWR (CANDU)
- Status: Operable; Units 3–8 are included in the ongoing Major Component Replacement program.
Why It Is One of the Largest
Bruce's exceptional total capacity comes from having eight reactors at one site, divided between Bruce A and Bruce B. The reactors use CANDU technology, which uses pressurized heavy water and natural uranium fuel.
The site is also undergoing a long-term Major Component Replacement (MCR) program covering Units 3–8. The work replaces major reactor components and is intended to extend the operating life of the units for decades.
Bruce also produces Cobalt-60, an important medical isotope used for applications including medical-device sterilization and cancer treatment.
2. Hongyanhe Nuclear Power Plant - China
Located in Dalian, Liaoning Province, the Hongyanhe Nuclear Power Plant is one of the world's largest nuclear power plant sites by combined net electrical capacity. The site has six operable pressurized water reactors with a combined net capacity of 6,366 MWe.
Key Facts
- Country: China
- Location: Dalian, Liaoning Province
- Net Capacity: 6,366 MWe
- Operable Reactors: 6
- Reactor Type: PWR (CPR-1000 and ACPR-1000)
- Status: Operable
Why It Is One of the Largest
Hongyanhe's large capacity comes from six reactors operating at the same site. Units 1–4 use CPR-1000 technology, while Units 5 and 6 use ACPR-1000 technology. Together, the six reactors provide more than 6.3 GW of net electrical capacity.
The plant is an important part of China's nuclear power fleet and supplies electricity to the regional grid. Its six-unit configuration allows a large amount of generating capacity to be concentrated at a single nuclear power site.
3. Tianwan Nuclear Power Plant - China
Located on the coast of the Yellow Sea in Lianyungang, Jiangsu Province, the Tianwan Nuclear Power Plant is one of the world's largest multi-unit nuclear power sites. The facility currently has six operable pressurized water reactors with a combined net electrical capacity of 6,240 MWe.
Key Facts
- Country: China
- Location: Lianyungang, Jiangsu Province
- Net Capacity: 6,240 MWe
- Operable Reactors: 6
- Reactor Type: PWR (VVER and Chinese-designed PWR technology)
- Status: Operable; Units 7 and 8 are under construction
Why It Is One of the Largest
Tianwan's large capacity comes from six reactors operating at the same site. Units 1 and 2 use Russian-designed VVER-1000 reactors, while Units 3–6 use newer reactor designs developed through cooperation between Russian and Chinese nuclear industries.
The six operable units provide more than 6.2 GW of combined net electrical capacity to China's electricity grid. Units 7 and 8 are being developed as additional reactors at the site, but their capacity is not included in this ranking because the ranking considers only currently operable reactors.
4. Qinshan Nuclear Power Complex - China
Situated on Hangzhou Bay in Haiyan County, Zhejiang Province, the Qinshan Nuclear Power Complex is one of China's oldest and most diverse nuclear power bases. Developed through several phases over many years, the complex currently has nine operable reactors with a combined net electrical capacity of 6,196 MWe.
Key Facts
- Country: China
- Location: Haiyan County, Zhejiang Province
- Net Capacity: 6,196 MWe
- Operable Reactors: 9
- Reactor Type: PWR and PHWR
- Status: Operable
Why It Is One of the Largest
Qinshan's large capacity comes from several reactor groups developed at the same nuclear complex. These include the original Qinshan Phase I reactor, the Qinshan Phase II and Phase III units, and the nearby Fangjiashan reactors.
The complex is notable for using different reactor technologies, including Chinese-designed pressurized water reactors and CANDU-6 heavy-water reactors. Its nine operable reactors provide more than 6.1 GW of combined net electrical capacity, making Qinshan an important part of China's nuclear power fleet.
5. Fuqing Nuclear Power Plant - China
Located along the coast of Xinghua Bay in Fuqing, Fujian Province, the Fuqing Nuclear Power Plant is one of China's largest multi-unit nuclear power sites. Operated by the China National Nuclear Corporation (CNNC), the plant has six operable pressurized water reactors with a combined net electrical capacity of 6,150 MWe.
Key Facts
- Country: China
- Location: Fuqing, Fujian Province
- Net Capacity: 6,150 MWe
- Operable Reactors: 6
- Reactor Type: PWR (CPR-1000 and Hualong One / HPR1000)
- Status: Operable
Why It Is One of the Largest
Fuqing's large capacity comes from six reactors operating at the same site. Units 1–4 use CPR-1000 pressurized water reactors, while Units 5 and 6 use the Hualong One (HPR1000) design.
Units 5 and 6 are particularly significant because they were among the first commercial reactors of the Hualong One design. With all six reactors combined, Fuqing has more than 6.1 GW of net electrical capacity, making it one of the largest nuclear power plants in China.
6. Yangjiang Nuclear Power Plant - China
Situated in Yangjiang, Guangdong Province, the Yangjiang Nuclear Power Plant is one of China's largest nuclear power facilities. Operated by China General Nuclear Power Group (CGN), the coastal station has six operable pressurized water reactors with a combined net electrical capacity of 6,000 MWe.
Key Facts
- Country: China
- Location: Yangjiang, Guangdong Province
- Net Capacity: 6,000 MWe
- Operable Reactors: 6
- Reactor Type: PWR (CPR-1000 and ACPR-1000)
- Status: Operable
Why It Is One of the Largest
Yangjiang's large capacity comes from six pressurized water reactors operating at the same site. Units 1–4 use the CPR-1000 design, while Units 5 and 6 use the ACPR-1000 design. Each unit has a net capacity of approximately 1,000 MWe, giving the plant a combined capacity of 6 GW.
Construction and commissioning took place in phases, with the first unit entering commercial operation in 2014 and the sixth unit following in 2019. With all six reactors now operable, Yangjiang remains one of China's largest multi-reactor nuclear power sites.
7. Hanul Nuclear Power Plant - South Korea
Located in Uljin, North Gyeongsang Province, the Hanul Nuclear Power Plant is one of South Korea's largest nuclear power sites. The plant currently has six operable pressurized water reactors with a combined net electrical capacity of 5,871 MWe.
Key Facts
- Country: South Korea
- Location: Uljin, North Gyeongsang Province
- Net Capacity: 5,871 MWe
- Operable Reactors: 6
- Reactor Type: PWR
- Status: Operable
Why It Is One of the Largest
Hanul's large generating capacity comes from six reactors operating at the same site. The six units have individual net capacities of roughly 950–1,000 MWe, giving the plant a combined capacity of nearly 5.9 GW.
The first six reactors were developed in stages using South Korean pressurized water reactor technology. Hanul is part of South Korea's established nuclear generation fleet and provides a significant amount of electricity to the country's power system.
8. Hanbit Nuclear Power Plant - South Korea
Situated along the Yellow Sea in Yeonggwang County, South Jeolla Province, the Hanbit Nuclear Power Plant, formerly known as Yeonggwang, is one of South Korea's largest nuclear power sites. Operated by Korea Hydro & Nuclear Power (KHNP), the station has six operable pressurized water reactors with a combined net electrical capacity of 5,813 MWe.
Key Facts
- Country: South Korea
- Location: Yeonggwang County, South Jeolla Province
- Net Capacity: 5,813 MWe
- Operable Reactors: 6
- Reactor Type: PWR
- Status: Operable
Why It Is One of the Largest
Hanbit's high capacity comes from six pressurized water reactors operating at the same site. The six units were developed in stages using different generations of reactor technology, including Combustion Engineering designs and South Korea's OPR-1000 reactors.
Together, the six operable units provide more than 5.8 GW of combined net electrical capacity, making Hanbit one of South Korea's largest multi-reactor nuclear power sites and an important part of the country's electricity system.
9. Gravelines Nuclear Power Plant - France
Situated on the North Sea coast near Dunkirk in northern France, the Gravelines Nuclear Power Plant is one of France's largest nuclear power sites. Operated by Électricité de France (EDF), the six-reactor complex has a combined net electrical capacity of 5,460 MWe.
Key Facts
- Country: France
- Location: Gravelines, Hauts-de-France
- Net Capacity: 5,460 MWe
- Operable Reactors: 6
- Reactor Type: PWR (CP1)
- Status: Operable
Why It Is One of the Largest
Gravelines consists of six pressurized water reactors developed as part of France's large-scale nuclear power program. The six units are rated at approximately 910 MWe net each, giving the plant a combined capacity of more than 5.4 GW.
The reactors were commissioned between 1980 and 1985, making Gravelines one of the long-established multi-unit nuclear power sites in France. Its coastal location provides access to seawater for the cooling systems used by the plant.
10. Barakah Nuclear Energy Plant - United Arab Emirates
Located in the Al Dhafra region of Abu Dhabi, the Barakah Nuclear Energy Plant is the United Arab Emirates' first nuclear power plant and one of the world's largest multi-unit nuclear facilities. Operated by Nawah Energy Company, the four-unit station has a combined net electrical capacity of 5,348 MWe.
Key Facts
- Country: United Arab Emirates
- Location: Al Dhafra, Abu Dhabi
- Net Capacity: 5,348 MWe
- Operable Reactors: 4
- Reactor Type: PWR (APR-1400)
- Status: Operable
Why It Is One of the Largest
Barakah's large capacity comes from four APR-1400 pressurized water reactors developed with South Korean nuclear industry technology. Each unit has a net electrical capacity of approximately 1,337 MWe, giving the plant a combined capacity of more than 5.3 GW.
The four reactors were commissioned in stages, with Unit 1 entering commercial operation in 2021 and the fourth unit entering commercial operation in 2024. With all four units operational, Barakah has established a large-scale nuclear generating site in the UAE.
11. Paluel Nuclear Power Plant - France
Located on the coast of the English Channel in Normandy, France, the Paluel Nuclear Power Plant is one of the country's largest nuclear power sites. Operated by Électricité de France (EDF), the station has four operable pressurized water reactors with a combined net electrical capacity of 5,320 MWe.
Key Facts
- Country: France
- Location: Paluel, Normandy
- Net Capacity: 5,320 MWe
- Operable Reactors: 4
- Reactor Type: PWR (P4 series)
- Status: Operable
Why It Is One of the Largest
Paluel achieves its high capacity through four large P4-series pressurized water reactors. Each unit has a net electrical capacity of approximately 1,330 MWe, giving the plant a combined capacity of more than 5.3 GW.
The four reactors were commissioned between 1984 and 1986 as part of France's large-scale nuclear power program. Located on the English Channel coast, the plant uses seawater for cooling its reactor units.
12. Cattenom Nuclear Power Plant - France
Located in the Grand Est region of northeastern France, close to the borders with Luxembourg and Germany, the Cattenom Nuclear Power Plant is one of France's largest nuclear power sites. Operated by Électricité de France (EDF), the plant has four operable pressurized water reactors with a combined net electrical capacity of 5,200 MWe.
Key Facts
- Country: France
- Location: Cattenom, Moselle, Grand Est
- Net Capacity: 5,200 MWe
- Operable Reactors: 4
- Reactor Type: PWR (P4 series)
- Status: Operable
Why It Is One of the Largest
Cattenom has four P4-series pressurized water reactors, each with a net electrical capacity of approximately 1,300 MWe. The four units were commissioned between 1986 and 1991, giving the plant a combined capacity of 5.2 GW.
Unlike France's coastal nuclear stations, Cattenom is located inland and uses cooling systems supplied by the Moselle River and the Mirgenbach reservoir. Its four large reactors make it an important multi-unit nuclear power site within France's electricity system.
13. Kori Nuclear Power Complex - South Korea
Located in Gijang County near Busan on South Korea's southeastern coast, the Kori Nuclear Power Complex is one of the country's major nuclear power sites. Operated by Korea Hydro & Nuclear Power (KHNP), the complex has five operable reactors included in this ranking, with a combined net electrical capacity of 4,605 MWe.
Key Facts
- Country: South Korea
- Location: Gijang County, Busan
- Net Capacity: 4,605 MWe
- Operable Reactors: 5
- Reactor Type: PWR
- Status: Operable
Why It Is One of the Largest
The Kori complex represents several generations of South Korea's nuclear power development. Kori Units 2, 3, and 4 use Westinghouse-designed pressurized water reactor technology, while Shin Kori Units 1 and 2 use the South Korean OPR-1000 design.
Kori Unit 1, South Korea's first commercial nuclear reactor, entered operation in 1978 and was permanently shut down in 2017. It is not included in the current capacity total. Shin Kori Units 3 and 4 are also excluded from this Kori grouping because they are administered as part of the Saeul Nuclear Power Plant site.
The five reactors included here provide a combined capacity of more than 4.6 GW, making the Kori complex one of South Korea's largest nuclear power sites.
14. Fangchenggang Nuclear Power Plant - China
Located along the Beibu Gulf in the Guangxi Zhuang Autonomous Region of southern China, the Fangchenggang Nuclear Power Plant is one of China's major multi-unit nuclear power sites. Operated by Guangxi Fangchenggang Nuclear Power Company, the plant has four operable pressurized water reactors with a combined net electrical capacity of 4,210 MWe.
Key Facts
- Country: China
- Location: Fangchenggang, Guangxi Zhuang Autonomous Region
- Net Capacity: 4,210 MWe
- Operable Reactors: 4
- Reactor Type: PWR (CPR-1000 and HPR1000)
- Status: Operable
Why It Is One of the Largest
Fangchenggang combines two generations of Chinese pressurized water reactor technology. Units 1 and 2 use the CPR-1000 design, while Units 3 and 4 use the HPR1000 (Hualong One) design. Units 3 and 4 were among the early Hualong One reactors developed for commercial operation in China.
The four operable reactors provide more than 4.2 GW of combined net electrical capacity, making Fangchenggang one of China's largest nuclear power sites. All four units are included in this ranking because they are currently operable.
15. Ningde Nuclear Power Plant - China
Located in Fuding, Ningde, in Fujian Province along China's southeastern coast, the Ningde Nuclear Power Plant is one of China's major multi-unit nuclear power sites. Operated by Fujian Ningde Nuclear Power Company, the plant has four operable pressurized water reactors with a combined net electrical capacity of 4,072 MWe.
Key Facts
- Country: China
- Location: Fuding, Ningde, Fujian Province
- Net Capacity: 4,072 MWe
- Operable Reactors: 4
- Reactor Type: PWR (CPR-1000)
- Status: Operable
Why It Is One of the Largest
Ningde's four operable reactors use the CPR-1000 pressurized water reactor design. Each unit has a net electrical capacity of approximately 1,018 MWe, giving the plant a combined capacity of 4.072 GW.
The four units were developed in stages, with the first unit entering commercial operation in 2013 and the fourth following in 2016. With all four reactors included, Ningde ranks among China's largest nuclear power plants by combined net electrical capacity.
16. Palo Verde Generating Station - United States
Located near Tonopah in Maricopa County, Arizona, the Palo Verde Generating Station is the largest nuclear power plant in the United States by net electrical capacity. Operated by Arizona Public Service (APS), the three-unit facility has a combined net electrical capacity of 3,937 MWe.
Key Facts
- Country: United States
- Location: Tonopah, Maricopa County, Arizona
- Net Capacity: 3,937 MWe
- Operable Reactors: 3
- Reactor Type: PWR (Combustion Engineering System 80)
- Status: Operable
Why It Is One of the Largest
Palo Verde has three high-capacity pressurized water reactors, with a combined net capacity of nearly 3.94 GW. The three units were commissioned between 1986 and 1988.
A notable feature of Palo Verde is its location in the Sonoran Desert, away from major natural sources of cooling water. The plant uses treated and recycled municipal wastewater for its cooling systems, making it different from many nuclear power plants that rely on nearby rivers, lakes, or coastal seawater.
The three operable reactors make Palo Verde the largest nuclear power plant in the United States by combined net electrical capacity.
17. Olkiluoto Nuclear Power Plant - Finland
Located on Olkiluoto Island in Eurajoki, Western Finland, the Olkiluoto Nuclear Power Plant is one of Europe's largest nuclear power sites. Operated by Teollisuuden Voima Oyj (TVO), the facility has three operable reactors with a combined net electrical capacity of 3,355 MWe.
Key Facts
- Country: Finland
- Location: Eurajoki, Satakunta
- Net Capacity: 3,355 MWe
- Operable Reactors: 3
- Reactor Type: BWR and PWR
- Status: Operable
Why It Is One of the Largest
Olkiluoto combines two older boiling water reactors with the newer European Pressurized Reactor (EPR). Olkiluoto 1 and 2 are Swedish-designed BWRs, each with a current net capacity of 890 MWe. Olkiluoto 3 is an EPR with a current net capacity of 1,575 MWe.
Olkiluoto 3 began regular electricity production in April 2023 and commercial operation in May 2023.
Together, the three operable reactors provide more than 3.3 GW of combined net electrical capacity, making Olkiluoto one of Finland's largest and most important nuclear power sites.
18. Taishan Nuclear Power Plant - China
Located in Taishan, Guangdong Province, along the coast of southern China, the Taishan Nuclear Power Plant is one of the world's largest nuclear power sites using the European Pressurized Reactor (EPR) design. The plant has two operable pressurized water reactors with a combined net electrical capacity of 3,320 MWe.
Key Facts
- Country: China
- Location: Taishan, Guangdong Province
- Net Capacity: 3,320 MWe
- Operable Reactors: 2
- Reactor Type: PWR (EPR-1750)
- Status: Operable
Why It Is One of the Largest
Taishan achieves more than 3.3 GW of capacity with only two reactors. Each EPR unit has a net electrical capacity of 1,660 MWe, making these among the highest-capacity individual nuclear reactors in operation.
Taishan 1 was the first EPR reactor in the world to achieve grid connection in June 2018, and entered commercial operation in December 2018. Taishan 2 followed with grid connection in June 2019 and commercial operation in September 2019.
With both reactors operable, Taishan provides 3.32 GW of combined net electrical capacity, placing it among the world's largest nuclear power plants by plant-site capacity.
19. Shidaowan Guohe One Nuclear Power Plant - China
Located in Shandong Province, China, the Shidaowan Guohe One Nuclear Power Plant is one of the world's largest nuclear power sites by combined net electrical capacity. The plant has two operable CAP1400 pressurized water reactors with a combined net electrical capacity of 2,838 MWe.
Key Facts
- Country: China
- Location: Shandong Province
- Net Capacity: 2,838 MWe
- Operable Reactors: 2
- Reactor Type: PWR (CAP1400)
- Status: Operable
Why It Is One of the Largest
Shidaowan Guohe One consists of two CAP1400 pressurized water reactors. Each reactor has a net electrical capacity of 1,419 MWe, giving the two-unit plant a combined capacity of 2,838 MWe.
Unit 1 achieved grid connection in October 2024, followed by Unit 2 in September 2025. The CAP1400 is a Chinese-developed large-scale pressurized water reactor design derived from the AP1000 technology platform. With both reactors operable, Shidaowan Guohe One ranks among the world's largest nuclear power plants by combined operable net capacity.
20. Saeul Nuclear Power Plant - South Korea
Located in Ulju County, Ulsan Metropolitan City, on the southeastern coast of South Korea, the Saeul Nuclear Power Plant is one of the country's major modern nuclear power sites. Operated by Korea Hydro & Nuclear Power (KHNP), the plant has two operable pressurized water reactors with a combined net electrical capacity of 2,784 MWe.
Key Facts
- Country: South Korea
- Location: Ulju County, Ulsan Metropolitan City
- Net Capacity: 2,784 MWe
- Operable Reactors: 2
- Reactor Type: PWR (APR-1400)
- Status: Operable; Units 3 and 4 are not included in the ranked capacity.
Why It Is One of the Largest
Saeul 1 and Saeul 2 use the APR-1400 pressurized water reactor design. Each unit has a net electrical capacity of 1,392 MWe, giving the two-unit plant a combined capacity of 2,784 MWe.
Saeul 1 entered commercial operation in December 2016, while Saeul 2 began commercial operation in August 2019. Saeul 3 has received its operating licence and is undergoing power-ascension testing, while Saeul 4 remains under development. Their capacity is excluded from this ranking because the ranking considers only currently operable reactors.
With more than 2.7 GW of combined net electrical capacity, Saeul is one of South Korea's largest nuclear power sites by operable plant capacity.
Largest Nuclear Power Plants by Country
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| Country-wise distribution of the world's Top 20 largest nuclear power plants, led by China, South Korea, and France. |
| Country | Number of Top 20 Plants | Total Top 20 Operable Capacity (MWe) | Largest Operating Plant |
|---|---|---|---|
| China | 9 | 45,392 | Hongyanhe (6,366 MWe) |
| South Korea | 4 | 19,073 | Hanul (5,871 MWe) |
| France | 3 | 15,980 | Gravelines (5,460 MWe) |
| Canada | 1 | 6,478 | Bruce (6,478 MWe) |
| United Arab Emirates | 1 | 5,348 | Barakah (5,348 MWe) |
| United States | 1 | 3,937 | Palo Verde (3,937 MWe) |
| Finland | 1 | 3,355 | Olkiluoto (3,355 MWe) |
1. China: The Largest Concentration of Top-Ranked Plants
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| China leads the global ranking with nine Top 20 nuclear power plants delivering 45,392 MWe of combined operable net capacity. |
China's representation includes Hongyanhe, Tianwan, Qinshan, Fuqing, Yangjiang, Fangchenggang, Ningde, Taishan, and Shidaowan Guohe One. Several of these sites use multiple reactors at the same location, while newer Chinese reactor designs such as Hualong One and CAP1400 are also represented.
China continues to add new nuclear reactors, so its position in global rankings can change as additional units become operable.
2. South Korea: High-Capacity Multi-Unit Sites
South Korea has four plants in the Top 20, representing 19,073 MWe of combined operable net capacity.
The country's largest sites in this ranking include Hanul, Hanbit, Kori, and Saeul. These facilities contain multiple pressurized water reactors from different generations, including OPR-1000 and APR-1400 designs. The combination of several reactors at individual sites gives South Korea some of the world's highest-capacity nuclear facilities.
3. France: Large Standardized Reactor Sites
France has three plants in the Top 20, with a combined capacity of 15,980 MWe.
The country's largest sites were developed primarily with standardized pressurized water reactor designs. Gravelines has six reactors, while Paluel and Cattenom each have four large P4-series reactors. This approach allowed France to concentrate several reactors at individual sites and build large generating facilities within its national nuclear fleet.
4. Canada: The Bruce Nuclear Generating Station
Canada has one plant in the Top 20: Bruce Nuclear Generating Station, with 6,478 MWe of combined net capacity.
Bruce stands out because eight CANDU reactors are located across the Bruce A and Bruce B generating stations. Its large capacity comes from the number of reactors concentrated at the site rather than from a single exceptionally large reactor.
5. United Arab Emirates: A Four-Unit Modern Nuclear Site
The Barakah Nuclear Energy Plant gives the United Arab Emirates one of the largest single nuclear sites in the world, with 5,348 MWe across four APR-1400 reactors.
Unlike older nuclear sites that were expanded over several decades, Barakah was developed as a four-unit project using the same basic reactor design. All four units are included in this ranking because they are operable.
6. United States: Palo Verde Leads the Top 20
The United States has one plant in the Top 20: Palo Verde Generating Station in Arizona, with 3,937 MWe of combined net capacity.
Palo Verde reaches this level through three large pressurized water reactors. Although the United States has a large nuclear fleet overall, many American nuclear sites have fewer reactors than the largest multi-unit complexes included in this ranking.
7. Finland: Olkiluoto
Finland is represented by the Olkiluoto Nuclear Power Plant, with 3,355 MWe of combined net capacity from three operable reactors.
Olkiluoto combines two boiling water reactors with the newer Olkiluoto 3 EPR. The three units demonstrate how a nuclear site can reach multi-gigawatt capacity through a combination of older reactors and a newer high-capacity unit.
Largest Nuclear Power Plant vs. Largest Nuclear Reactor
The terms largest nuclear power plant and largest nuclear reactor describe two different measurements. A nuclear power plant can contain several reactors at the same site, while a reactor is a single generating unit.
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| Comparison between multi-unit plant site capacity (e.g., Bruce) and individual single-reactor capacity (e.g., Taishan EPR). |
Multi-Unit Sites vs. High-Output Reactors
A plant does not need to have the world's most powerful individual reactor to achieve the highest total capacity. Several medium- or high-capacity reactors at one site can produce a greater combined capacity than one or two very large reactors.
A nuclear power plant uses heat from its reactors to produce steam that drives turbines and generates electricity. This steam-generation principle is also relevant when comparing nuclear facilities with conventional power plant boilers, which convert heat into steam for power generation.
- Bruce Nuclear Generating Station (Canada): Ranks #1 with 6,478 MWe from eight operable CANDU reactors.
- Taishan Nuclear Power Plant (China): Provides 3,320 MWe from two EPR reactors, with each unit rated at 1,660 MWe net.
- Olkiluoto Nuclear Power Plant (Finland): Has three operable reactors with a combined capacity of 3,355 MWe, including Olkiluoto 3 at 1,575 MWe net.
| Metric | Facility / Unit | Net Capacity (MWe) | Operational Scope |
|---|---|---|---|
| Largest Plant by Combined Site Capacity | Bruce Nuclear Generating Station | 6,478 | 8 operable reactors combined |
| High-Capacity Multi-Reactor Site | Hongyanhe Nuclear Power Plant | 6,366 | 6 operable reactors combined |
| High-Capacity Individual Reactor | Taishan Unit 1 or Unit 2 | 1,660 | Single EPR unit |
| High-Capacity European Reactor | Olkiluoto Unit 3 | 1,575 | Single EPR unit |
Therefore, the largest nuclear power plant and the largest individual nuclear reactor are not necessarily the same thing. This article ranks complete plant sites based on their combined operable net capacity, rather than ranking individual reactor units.
Operational Status of the World's Largest Nuclear Power Plants
The operating status of nuclear reactors can change over time because of scheduled refuelling, maintenance, refurbishment, regulatory requirements, or permanent shutdown. For this reason, the capacity figures in this ranking are based on the operable reactors included at each plant site or complex.
An operable reactor may be temporarily offline for activities such as refuelling, maintenance, or planned work while remaining part of the plant's operating fleet. Temporary outages do not remove a reactor from the plant's rated operable capacity.
What Is Included and Excluded?
The ranking includes:
- Operable reactors: Units classified as part of the current operating reactor fleet.
- Temporary outages: Reactors temporarily offline for refuelling, maintenance, or other planned work.
- Life-extension work: Operable reactors undergoing major refurbishment or component replacement while remaining part of the operating fleet.
The ranking excludes:
- Reactors under construction: Units that have not yet become operable.
- Permanently shut-down reactors: Units that have permanently ended commercial operation.
- Decommissioned reactors: Units that are no longer part of the operating nuclear fleet.
Several plants in the Top 20 have additional reactors under construction or being developed. For example, Tianwan and Saeul have additional units that are not included in their ranked capacity because they are not yet operable.
This approach keeps the ranking focused on the combined net electrical capacity of currently operable reactors at each plant site or complex. Reactor status and capacity can change as new units become operable, existing units receive capacity upgrades, or older reactors permanently shut down. The ranking should therefore be updated when new authoritative reactor data becomes available.
Key Takeaways
- World's Largest Operating Plant: The Bruce Nuclear Generating Station in Canada ranks first with 6,478 MWe of combined net electrical capacity from eight operable CANDU reactors.
- China's Strong Representation: China has nine plants in the Top 20, with a combined capacity of 45,392 MWe in this ranking.
- South Korea and France: South Korea has four plants in the Top 20, while France has three, reflecting their large multi-unit nuclear power sites.
- Site Capacity vs. Reactor Capacity: A plant's total capacity is determined by the combined capacity of its operable reactors. A multi-reactor site can therefore have a much higher total capacity than a site with only one or two units.
- High-Capacity Individual Reactors: The Taishan Nuclear Power Plant demonstrates the high output of modern reactor designs, with each of its two EPR units rated at 1,660 MWe net.
- Net Electrical Capacity: This ranking uses net electrical capacity (MWe) rather than gross capacity or annual electricity generation.
- Operable Reactors Only: Reactors under construction, permanently shut down, or decommissioned are excluded from the ranked capacity totals.
- A Changing Ranking: Global rankings can change as new reactors become operable, existing units receive capacity upgrades, or older reactors permanently retire.
Frequently Asked Questions
1. What is the largest nuclear power plant in the world?
The Bruce Nuclear Generating Station in Ontario, Canada, ranks first in this list with a combined net electrical capacity of 6,478 MWe from eight operable CANDU reactors.
2. Which country has the largest number of nuclear power plants in the Top 20?
China has the largest representation, with nine nuclear power plants in the Top 20: Hongyanhe, Tianwan, Qinshan, Fuqing, Yangjiang, Fangchenggang, Ningde, Taishan, and Shidaowan Guohe One. Together, these plants account for 45,392 MWe of combined operable net capacity in this ranking.
3. What is the difference between a nuclear power plant and a nuclear reactor?
A nuclear reactor is an individual generating unit, while a nuclear power plant can contain several reactors at the same site. This ranking measures the combined net electrical capacity of the operable reactors included at each plant site or complex.
4. Which nuclear power plant has the most powerful individual reactor?
The Taishan Nuclear Power Plant in Guangdong, China, has two high-capacity EPR reactors. Each unit has a net electrical capacity of 1,660 MWe, making them among the highest-capacity individual reactors represented in this ranking.
5. How are the world's largest nuclear power plants ranked?
The plants are ranked by their combined net electrical capacity (MWe) from currently operable reactors at each site or complex. Reactors under construction, permanently shut down, or decommissioned are excluded from the ranked capacity totals.
6. Why can a nuclear power plant have a higher capacity than an individual reactor?
A nuclear power plant can contain multiple reactors, so their individual capacities can be combined to determine the total capacity of the site. For example, Bruce reaches 6,478 MWe by combining the net capacities of eight operable reactors.
7. Can the ranking of the world's largest nuclear power plants change?
Yes. The ranking can change when new reactors become operable, existing reactors receive capacity upgrades, or older reactors permanently shut down. Nuclear plant capacity and operating-status data should therefore be updated periodically.
Conclusion
The world's largest nuclear power plants show how multi-unit sites and high-capacity reactor designs can provide several gigawatts of electrical generating capacity from a single location. By combining multiple reactors at one site, these facilities can achieve much higher total capacity than plants with only one or two units.
The Bruce Nuclear Generating Station in Ontario, Canada, ranks first in this list with 6,478 MWe of combined net electrical capacity from eight operable CANDU reactors. China has the largest representation, with nine plants in the Top 20 and a combined capacity of 45,392 MWe. South Korea has four plants, while France has three plants in the ranking.
The ranking also highlights the difference between plant-site capacity and individual reactor capacity. Multi-unit sites reach multi-gigawatt capacity by combining several reactors, while modern designs such as the EPR units at Taishan Nuclear Power Plant provide very high capacity from individual reactors, at 1,660 MWe net each.
This ranking is based on the combined net electrical capacity of currently operable reactors at each plant site or complex. The global ranking can change as new reactors become operable, existing units receive capacity upgrades, or older reactors permanently shut down.
Data Sources
The capacity metrics, operational classifications, and reactor information in this ranking are based primarily on authoritative nuclear industry sources:
- IAEA Power Reactor Information System (PRIS): Used for reactor-level information, including operating status, commercial operation dates, and electrical capacity.
- World Nuclear Association (WNA) Reactor Database: Used to cross-check reactor status, capacity figures, and reactor specifications.
- Official Utility and Operator Sources: Used for additional plant-specific information, including site details, reactor technology, commissioning information, and major refurbishment or upgrade programs.
All capacity figures in this ranking represent operable net electrical capacity (MWe). Net capacity refers to the rated electrical generating capacity available after accounting for the electricity consumed by the plant's own systems. It should not be confused with the amount of electricity a plant actually generates over a year.
Because reactor operating status and capacity can change over time, this ranking represents a current snapshot of the world's largest nuclear power plants based on the operable net capacity used for this analysis.
