Top 10: Nuclear Energy Companies
At the 2023 UN Climate Change Conference more than 20 nations made a landmark pledge to triple global nuclear energy capacity by 2050.
The declaration highlighted a profound strategic shift in power supply due to the reality of climate change and urgent need for energy security.
Despite not being a type of renewable energy, nuclear has historically been one of the largest global contributors of carbon-free electricity, and it has significant potential to contribute to power sector decarbonisation.
The global nuclear fleet is made up of around 420 reactors and supplies 10% of the world’s electricity according to IEA.
Energy Digital has ranked some of the largest companies in the world generating electricity using nuclear power, ordering them by the amount of energy output the produce.
10. Energoatom
Energy Output: 86.4 TWh (2025)
CEO: Petro Kotin
Founded: 1996
Founded in 1996, Energoatom operates in Ukraine and has 15 reactors across four nuclear power plants.
The largest plant, Zaporizhzhia, houses six reactors on its own.
The company is one of the largest electricity producers in Ukraine, supplying roughly 55% of the country's demand annually.
It plays a critical role in Ukraine’s energy security, energy independence, sustainable economic development and the transition to a carbon-free energy future.
9. Bruce Power
Energy Output: 145 TWh- 2024
CEO: Eric Chassard
Founded: 2001
Bruce Power is Canada’s only private nuclear energy generator, established in 2001 and operating in Ontario.
The site has two generating stations with eight reactors between them.
The company produces around 30% of Ontario’s electricity.
Bruce Power made an investment to refurbish six of its units, with the aim to ensure operations until 2064.
Beyond electricity, Bruce Power produces a supply of Cobalt-60 that is vital for medical sterilisation and cancer treatment.
8. Constellation Energy
Energy Output:150 TWh - 2024
CEO: Joseph Dominguez
Founded: 1999
Constellation Energy is an American leading energy provider in Baltimore.
For 10 years consecutively it was recognised as the nation's largest producer of clean, carbon-free energy.
The company houses 21 reactors across 12 sites, generating enough electricity to power roughly 15 million homes.
Constellation Energy is actively promoting the offering of nuclear powered electricity plans for residential customers, enabling consumers to choose 100% carbon free nuclear energy to power their home.
Recently Constellation has announced commitments to spend billions of dollars on nuclear energy to fuel economic growth in Pennsylvania.
Joseph Dominguez, President and CEO, Constellation said: “These investments will help power innovation in AI and other industries that will define the future for Pennsylvania and all Americans.”
7. Tennessee Valley Authority (TVA)
Energy Output: 152.9 TWh -2025
CEO: Jeff Lyash
Founded: 1933
TVA is the third largest power fleet in the US.
The company has seven nuclear units across three plants.
As well as nuclear power, TVA has a large energy portfolio including hydroelectric, natural gas, coal, wind and solar power.
TVA recently announced it has completed 10 new aeroderivative gas turbines.
Justin McBath, TVA Senior Project Manager said: ““They have a fast-start option,
“You can go from a cold engine to full power in five minutes, generating 50 megawatts per unit – and these will actually generate up to around 57 to 59 megawatts under the right conditions.”
6. Korea Electric Power Corporation (KEPCO)
Energy Output: 180.5 TWh -2024
CEO: Kim Dong-Cheo
Founded: 1898
KEPCO’s origins span back to 1898, only becoming a state owned empire in 1961.
The company has more than 40 years of experience in developing and managing nuclear powerplants.
KEPCO as a whole owns roughly 65% of Korea’s total electricity generation capacity, with nuclear power accounting for 96% of its low carbon electricity.
It has 26 nuclear reactors across 25 nuclear sites.
5. Duke Energy
Energy Output: 195.4 TWh
CEO: Lynn Good
Founded: 1904
Duke Energy operates 11 nuclear units at six sites across North and South Carolina, in the US.
It has set industry benchmarks in safety, efficiency and cost effectiveness in more than 50 years of operation.
Recently the company invested US$789,000 into Florida colleges.
Melissa Seixas, President, Duke Energy Florida says: “Our goal is to equip this next generation with access to advanced technology and immersive learning opportunities as they prepare for their future careers.”
4. China National Nuclear Corporation (CNNC)
Energy Output: 195.4 TWh - 2025
CEO: Yu Jianfeng
Founded: 1955
CNNC has 25 reactors currently in operation, with 18 more under construction.
The company has a large portfolio covering nuclear power generation, nuclear fuel, uranium exploration, mining, nuclear engineering and construction, nuclear technology applications and nuclear environmental protection.
CNNC has 180,000 employees and aims to improve reliability, intelligent operations and maintenance of current nuclear technology.
The operation provides for roughly 42% of China’s nuclear energy market.
3. Rosatom
Energy Output: 195.4 TWh - 2025
CEO: Yu Jianfeng
Founded: 1955
Rosatom was established in 2007 and is Russia's state atomic energy corporation.
With headquarters based in Moscow, the company integrated the entire nuclear fuel cycle.
Rosatom is a major player in the global nuclear market share and leads with a 70% share of the nuclear reactor export market.
The company has 11 nuclear power sites across Russia with 38 nuclear units.
Rosatom’s long-term strategy targets developing inherently safe reactors with closed fuel cycles and fast reactors by 2050.
2. China General Nuclear (CGN)
Energy Output: 242.2 TWh - 2024
CEO: Yang Changli
Founded: 1994
CGN is China’s largest state-owned nuclear energy corporation, controlling more than 50% of China’s domestic nuclear power market.
Founded in 1994, it now operates around 23 reactors that are stored in eight nuclear power stations.
The group is also committed to clean energy diversification, actively developing wind, solar and hydroelectric power plants alongside its nuclear operations.
CGN has made advances in nuclear technology creating the Hualong One (HPR1000), a third generation pressurised water reactor, it is created to eliminate significant radioactive releases even under extreme conditions, mitigating the effects of accidents.
CGN is the world’s largest nuclear power construction company, with involvement in international projects including the UK, Pakistan, Romania and Argentina.
1. Électricité de France (EDF)
Energy Output: 358-364 TWh -2024
CEO: Simone Rossi
Founded: 1946
EDF was founded in 1946 as a French electric utility company.
Although headquartered in Paris it has a dominant presence in the majority of Europe.
EDF operates 56 active nuclear reactors in France housed in 18 power plants; these reactors generate low carbon power critical for the country’s energy security and climate goals.
The company is also a major nuclear operator in the UK, and currently generates 20% of the UK's electricity through eight power stations.
Its newest project, Sizewell C has recently announced it has its final investment decision that the build can be completed.
Julia Pyke and Nigel Cann, Joint Managing Directors of Sizewell C, said: “By investing in Sizewell C, they are laying the foundations for a more secure, cleaner and more affordable energy system.
“Because 70% of our construction spend will be in the UK … they will also help to create thousands of great jobs and new opportunities for people and businesses up and down the country.”
EDF is pursuing its ambition to contribute to carbon neutrality by 2050.
