How Many Countries in the World Use Nuclear Energy?

Nuclear power has been a significant source of electricity since the 1950s, when the first commercial nuclear power stations began operating. Today, nuclear energy plays a vital role in the global energy landscape. Approximately 9% of the world’s electricity is generated from nuclear power, coming from about 440 power reactors across the globe. Furthermore, nuclear energy contributes about one-quarter of the world’s low-carbon electricity, making it the second-largest source of low-carbon power worldwide, after hydropower.

More than 50 countries around the world utilize nuclear technology. While 31 countries, plus Taiwan, operate commercial nuclear power plants, over 50 countries benefit from nuclear energy through approximately 220 research reactors. These research reactors are not only crucial for scientific advancement and training but also for the production of essential medical and industrial isotopes.

Nuclear technology harnesses the energy released from splitting atoms of certain elements, a process first developed in the 1940s. Initially focused on military applications during World War II, the 1950s saw a shift towards the peaceful use of nuclear fission for power generation. The ability to control this powerful energy source opened up new possibilities for electricity production. For a deeper dive into its origins, explore the History of Nuclear Energy.

Civilian nuclear power boasts approximately 20,000 reactor years of operational experience. Nuclear power plants are currently operational in 31 countries and Taiwan. The reliance on nuclear-generated power extends even further through regional transmission grids, especially in Europe, where many countries depend on nuclear energy produced in neighboring nations.

The nuclear industry has evolved into a globalized sector since its commercial beginnings in the 1960s, when clear divisions existed between Eastern and Western industries. Today, international commerce defines the nuclear industry. Components for a reactor being constructed in Asia might originate from countries as diverse as South Korea, Canada, Japan, France, Germany, and Russia. Similarly, uranium fuel could begin in Australia or Namibia, undergo conversion in France, enrichment in the Netherlands, deconversion in the UK, and fuel fabrication in South Korea before finally powering a reactor in the UAE.

The applications of nuclear technology reach far beyond electricity generation, impacting various aspects of modern life across many countries. From helping to control disease outbreaks to assisting doctors in diagnosis and treatment, and even powering space exploration missions, nuclear technologies are central to global sustainable development efforts. Further information is available on the Nuclear Energy and Sustainable Development page.

Key Statistics: Nuclear Energy Usage Across the Globe

In 2023, nuclear plants globally supplied 2602 TWh of electricity, an increase from 2545 TWh in 2022, demonstrating a consistent growth in nuclear energy production worldwide.

Figure 1: Nuclear electricity production 1970-2023 showing global trends in nuclear power generation across different regions (source: World Nuclear Association, IAEA PRIS)

Figure 2: Global electricity production by source in 2022, illustrating the proportion of nuclear energy in the world’s energy mix (source: International Energy Agency)

In 2023, fourteen countries generated at least 25% of their electricity from nuclear power, showcasing a significant reliance on nuclear energy in certain nations. France leads with approximately 70% of its electricity from nuclear sources. Ukraine, Slovakia, and Hungary each obtain about half of their electricity from nuclear power. Japan, historically reliant on nuclear for over a quarter of its electricity, is expected to return to similar levels.

Figure 3: Nuclear generation by country in 2023, highlighting the countries with the highest nuclear electricity production (source: World Nuclear Association, IAEA PRIS)

Developments in 2024: Expanding Nuclear Energy Across Countries

While specific details for 2024 developments are continuously updated, the global nuclear industry is marked by ongoing activities in grid connections, construction starts, and reactor shutdowns, reflecting the dynamic nature of nuclear energy across different countries. For the most current information, resources like the World Nuclear Association provide up-to-date reports.

World Overview: Countries and Their Nuclear Programs

Nuclear power development is a global endeavor, involving countries across all continents. The table below provides a detailed country-level overview of nuclear electricity generation and reactor status. For in-depth information on specific countries, the Country Profiles section of the World Nuclear Association’s Information Library offers extensive resources.

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 Around the World

Bangladesh and Turkey are at the forefront of countries constructing their first nuclear power plants, marking their entry into the list of nations utilizing nuclear energy. Numerous other countries are also actively exploring and moving towards adopting nuclear energy for power production, indicating a growing global interest. More details can be found on the Emerging Nuclear Energy Countries page.

Improved Performance from Existing Reactors Globally

The efficiency and performance of nuclear reactors have significantly improved over the years across all operating countries. Over the past four decades, there has been a notable increase in the proportion of reactors achieving high capacity factors, demonstrating enhanced operational reliability worldwide.

Figure 4: Long-term trends in nuclear reactor capacity factors illustrating the increasing efficiency of nuclear reactors over time (source: World Nuclear Association, IAEA PRIS)

It is also important to note that recent data shows no significant age-related decline in the average capacity factor for reactors in the last five years, indicating sustained performance even as reactors age in the countries that operate them.

Figure 5: Mean capacity factor from 2018-2023 by age of reactor, showing consistent performance across different reactor age groups (source: World Nuclear Association, IAEA PRIS)

The Growing Need for New Generating Capacity in Many Countries

Globally, there is an increasing demand for new electricity generating capacity. This need is driven by the necessity to replace aging fossil fuel power plants, especially coal-fired plants known for high carbon dioxide emissions, and to meet the rising electricity demands in many countries. In 2022, fossil fuels accounted for 61% of global electricity generation. Despite the growth in renewable energy sources, the contribution of fossil fuels to power generation has remained relatively stable over the last 15 years (66.5% in 2005).

The OECD International Energy Agency (IEA) provides annual energy scenarios. The IEA’s World Energy Outlook 20231 outlines a Net Zero Emissions by 2050 Scenario (NZE) that aims to limit global warming to 1.5°C while ensuring universal access to modern energy by 2030. This NZE scenario projects a significant increase in nuclear capacity to 916 GWe by 2050. Further details are available on the IEA Scenarios and the Outlook for Nuclear Power information page.

Other Nuclear Reactors Beyond Power Plants: Global Applications

Beyond commercial power plants, approximately 220 research reactors operate in over 50 countries, with more under construction. These reactors are essential for research, training, and the production of medical and industrial isotopes, highlighting the diverse benefits of nuclear technology across numerous nations.

Marine propulsion is another significant application, primarily within major navies. For five decades, nuclear reactors have powered submarines and large surface vessels. Over 160 ships, mainly submarines, are powered by about 200 nuclear reactors, accumulating over 13,000 reactor years of experience. While many nuclear submarines from the Cold War era have been decommissioned by Russia and the USA, this application remains vital for specific countries.

Russia also operates a fleet of nuclear-powered icebreakers and is expanding this fleet. Additionally, they have connected a floating nuclear power plant with two 32 MWe reactors to the grid in Pevek, a remote arctic region. These reactors, adapted from icebreaker designs, demonstrate the innovative deployment of nuclear technology in various geographical contexts.

For comprehensive information, see the page on The Many Uses of Nuclear Technology.

Notes & References

References

1. OECD International Energy Agency, World Energy Outlook 2023 [Back]
2. 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