Nuclear energy stands as a critical component of the world’s electricity supply, especially as nations strive for low-carbon energy solutions. Since the dawn of commercial nuclear power in the 1950s, it has grown to contribute significantly to the global energy mix. Currently, approximately 9% of the world’s electricity is generated from nuclear sources, thanks to around 440 operational power reactors across the globe. Moreover, nuclear power is responsible for about a quarter of the world’s low-carbon electricity production, solidifying its position as the second-largest source of low-carbon power worldwide.
Beyond electricity generation, over 50 countries harness nuclear technology through approximately 220 research reactors. These reactors are instrumental not only in scientific advancement and training but also in producing vital medical and industrial isotopes.
The foundation of nuclear technology lies in harnessing the energy released from splitting atoms of specific elements. Originating in the 1940s, initial research during World War II centered on military applications. However, the 1950s marked a shift towards peaceful applications, particularly controlling nuclear fission for electricity generation. For a deeper dive into its origins, explore the History of Nuclear Energy.
Today, civil nuclear power boasts an impressive track record of around 20,000 reactor-years of operational experience. Nuclear power plants are actively running in 31 countries and Taiwan. Interestingly, the reliance on nuclear-generated power extends even further geographically. Many more countries, particularly within Europe, benefit from nuclear energy through interconnected regional transmission grids. This international aspect highlights how energy solutions transcend national borders.
The nuclear industry, once divided along Cold War lines, is now a model of international collaboration. A nuclear reactor being constructed in Asia today might incorporate components from a diverse range of nations, including South Korea, Canada, Japan, France, Germany, and Russia. Similarly, the journey of uranium fuel can be equally international. Uranium sourced from Australia or Namibia could power a reactor in the UAE, having undergone processing stages in France, the Netherlands, the UK, and South Korea. This global interconnectedness underscores the worldwide scale of nuclear energy.
The applications of nuclear technology are far-reaching, extending well beyond just low-carbon electricity. It plays a crucial role in healthcare, helping to combat diseases and providing advanced diagnostic and treatment tools. Furthermore, nuclear power is essential for ambitious space exploration missions. These diverse applications position nuclear technologies as a cornerstone in global sustainable development efforts. Learn more about this connection at Nuclear Energy and Sustainable Development.
Key Global Nuclear Statistics
In 2023, nuclear power plants globally delivered 2602 TWh of electricity, marking an increase from 2545 TWh in 2022. This demonstrates a consistent and growing contribution to global energy needs.
Figure 1: Global nuclear electricity production from 1970 to 2023 (Source: World Nuclear Association, IAEA PRIS)
Figure 2: Global electricity production by source in 2022, showcasing nuclear’s role (Source: International Energy Agency)
In 2023, fourteen countries achieved a significant milestone, generating at least 25% of their electricity from nuclear power. France leads globally, with nuclear energy accounting for approximately 70% of its electricity. Ukraine, Slovakia, and Hungary also heavily rely on nuclear power, each generating about half of their electricity from this source. Japan, historically reliant on nuclear for over a quarter of its electricity, is anticipated to return to similar levels of nuclear energy consumption in the near future.
Figure 3: Nuclear electricity generation by country in 2023 (Source: World Nuclear Association, IAEA PRIS)
Current Nuclear Power Developments in 2024
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World Nuclear Power Overview: Country by Country
Nuclear power development is a worldwide endeavor, engaging nations across all continents. For detailed insights into specific countries and their nuclear programs, the Country Profiles section of the World Nuclear Association’s Information Library offers extensive information.
| COUNTRY | NUCLEAR ELECTRICITY GENERATION 2023 | REACTORS OPERABLE | REACTORS UNDER CONSTRUCTION | REACTORS PLANNED | REACTORS PROPOSED | URANIUM REQUIRED 2024 |
|---|---|---|---|---|---|---|
| TWh | % | No. | MWe | No. | MWe | |
| Argentina | 9.0 | 6.3 | 3 | 1641 | 1 | 29 |
| Armenia | 2.5 | 31.1 | 1 | 416 | 0 | 0 |
| Bangladesh | 0 | 0 | 0 | 0 | 2 | 2400 |
| Belarus | 11.0 | 28.6 | 2 | 2220 | 0 | 0 |
| Belgium | 31.3 | 41.2 | 5 | 3908 | 0 | 0 |
| Brazil | 13.7 | 2.2 | 2 | 1884 | 1 | 1405 |
| Bulgaria | 15.5 | 40.4 | 2 | 2006 | 0 | 0 |
| Canada | 83.5 | 13.7 | 17 | 12,669 | 0 | 0 |
| China | 406.5 | 4.9 | 58 | 56,888 | 29 | 33,165 |
| Czech Republic | 28.7 | 40.0 | 6 | 4212 | 0 | 0 |
| Egypt | 0 | 0 | 0 | 0 | 4 | 4800 |
| Finland | 32.8 | 42.0 | 5 | 4369 | 0 | 0 |
| France | 323.8 | 64.8 | 57 | 63,000 | 0 | 0 |
| Germany | 6.7 | 1.4 | 0 | 0 | 0 | 0 |
| Ghana | 0 | 0 | 0 | 0 | 0 | 0 |
| Hungary | 15.1 | 48.8 | 4 | 1916 | 0 | 0 |
| India | 44.6 | 3.1 | 23 | 7425 | 7 | 5900 |
| Iran | 6.1 | 1.7 | 1 | 915 | 1 | 1057 |
| Japan † | 77.5 | 5.6 | 33 | 31,679 | 2 | 2756 |
| Kazakhstan | 0 | 0 | 0 | 0 | 0 | 0 |
| Korea RO (South) | 171.6 | 31.5 | 26 | 25,825 | 2 | 2680 |
| Mexico | 12.0 | 4.9 | 2 | 1552 | 0 | 0 |
| Netherlands | 3.8 | 3.4 | 1 | 482 | 0 | 0 |
| Pakistan | 22.4 | 17.4 | 6 | 3262 | 1 | 1100 |
| Poland | 0 | 0 | 0 | 0 | 0 | 3 |
| Romania | 10.3 | 18.9 | 2 | 1300 | 0 | 0 |
| Russia | 204.0 | 18.4 | 36 | 26,802 | 6 | 4102 |
| Saudi Arabia | 0 | 0 | 0 | 0 | 0 | 0 |
| Slovakia | 17.0 | 61.3 | 5 | 2308 | 1 | 471 |
| Slovenia | 5.3 | 36.8 | 1 | 688 | 0 | 0 |
| South Africa | 8.2 | 4.4 | 2 | 1854 | 0 | 0 |
| Spain | 54.4 | 20.3 | 7 | 7123 | 0 | 0 |
| Sweden | 46.6 | 28.6 | 6 | 7008 | 0 | 0 |
| Switzerland | 23.4 | 32.4 | 4 | 2973 | 0 | 0 |
| Turkey | 0 | 0 | 0 | 0 | 4 | 4800 |
| Ukraine † ‡ | 50.0 | 50.7 | 15 | 13,107 | 2 | 1900 |
| UAE | 31.2 | 19.7 | 4 | 5348 | 0 | 0 |
| United Kingdom | 37.3 | 12.5 | 9 | 5883 | 2 | 3440 |
| USA | 779.2 | 18.6 | 94 | 96,952 | 0 | 0 |
| Uzbekistan | 0 | 0 | 0 | 0 | 0 | 0 |
| WORLD* | 2602 | c. 9% | 440 | 398,553 | 65 | 70,005 |
| TWh | % e | No. | MWe | No. | MWe |
67,517 tU = 79,619 t U3O8
Operable = Connected to the grid. Under Construction = First concrete for reactor poured, keel layed for floating plants. Planned = Approvals, funding or commitment in place, mostly expected to be in operation within the next 15 years. Proposed = Specific programme or site proposals; timing very uncertain.
* World figures include Taiwan, which generated a total of 17.2 TWh from nuclear in 2023 (accounting for 6.9% of Taiwan’s total electricity generation). As of January 2025 the island has one operable reactor with a net capacity of 938 MWe.
† Under Construction figures include a number of units where construction is currently suspended: Angra 3 (Brazil); Ohma 1 and Shimane 3 (Japan); Khmelnitski 3&4 (Ukraine).
‡ Ukraine 2023 electricity generation estimated.
Emerging Nuclear Energy Countries
Beyond the established nuclear nations, several countries are actively developing their nuclear energy capabilities. Bangladesh and Turkey are currently constructing their first nuclear power plants, marking their entry into the nuclear energy sector. Numerous other countries are also making significant strides towards adopting nuclear energy for power generation. Further details can be found on the Emerging Nuclear Energy Countries page. This expansion indicates a growing global interest in nuclear power.
Performance Improvements in Existing Nuclear Reactors
The operational efficiency of nuclear reactors has seen remarkable improvements over time. Over the past four decades, there’s been a significant increase in the proportion of reactors achieving high capacity factors. This means reactors are operating more consistently and effectively, maximizing their electricity output.
Figure 4: Long-term trends in nuclear reactor capacity factors, demonstrating improved performance (Source: World Nuclear Association, IAEA PRIS)
Notably, recent data shows no significant correlation between reactor age and capacity factor over the last five years. This suggests that with proper maintenance and technological upgrades, nuclear reactors can maintain high performance levels throughout their operational lifespan.
Figure 5: Average capacity factor from 2018-2023, categorized by reactor age, showing consistent performance (Source: World Nuclear Association, IAEA PRIS)
The Growing Need for New Electricity Generation Capacity
Globally, there is a pressing need for increased electricity generation capacity. This is driven by two primary factors: the necessity to replace aging fossil fuel power plants, particularly coal-fired plants known for their high carbon dioxide emissions, and the rising electricity demand in many countries. In 2022, a significant 61% of the world’s electricity was still generated from burning fossil fuels. Despite the growing popularity and investment in intermittent renewable energy sources, the contribution of fossil fuels to electricity generation has only marginally decreased in the last 15 years (from 66.5% in 2005). This highlights the ongoing challenge of transitioning away from fossil fuels.
The International Energy Agency (IEA) provides annual energy scenarios. Their World Energy Outlook 20231 outlines a Net Zero Emissions by 2050 Scenario (NZE). This scenario proposes a pathway to limit global average temperature increase to 1.5°C while ensuring universal access to modern energy by 2030. The IEA’s NZE scenario projects a substantial increase in nuclear capacity, reaching 916 GWe by 2050. Further information on these projections can be found on the IEA Scenarios and the Outlook for Nuclear Power page.
Beyond Power Plants: Other Applications of Nuclear Reactors
Besides commercial nuclear power plants, approximately 220 research reactors are operational in over 50 countries, with more under development. These reactors are vital for research, training, and the production of medical and industrial isotopes. Their widespread use underscores the diverse benefits of nuclear technology across various sectors and many countries.
Nuclear reactors are also crucial for marine propulsion, primarily in major navies. For over five decades, nuclear power has been essential for powering submarines and large surface vessels. Over 160 ships, mostly submarines, are propelled by approximately 200 nuclear reactors, accumulating over 13,000 reactor-years of experience in marine applications. While Russia and the USA have decommissioned many nuclear submarines from the Cold War era, nuclear marine technology remains significant.
Russia also operates a fleet of nuclear-powered icebreakers and is expanding this fleet. Additionally, Russia has connected a floating nuclear power plant, equipped with two 32 MWe reactors, to the grid in the remote Arctic region of Pevek. These reactors are adapted from those used in icebreakers, showcasing innovative applications of nuclear technology in remote locations.
Explore the broader spectrum of nuclear applications on the The Many Uses of Nuclear Technology page. This demonstrates that many countries benefit from nuclear technology in diverse ways beyond just electricity.
Notes & References
References
- OECD International Energy Agency, World Energy Outlook 2023 [Back]
- OECD International Energy Agency Statistics [Back]
General references
World Nuclear Association, World Nuclear Performance Report 2023
Related Information
Nuclear Energy and Sustainable Development
World Energy Needs & Nuclear Power
Plans For New Reactors Worldwide
The Many Uses of Nuclear Technology
What is Uranium? How Does it Work?
Financing Nuclear Energy
