The Role of Nuclear Energy in Mitigating Climate Change

How can an energy mix that includes nuclear power help to achieve global climate change goals? Banner image: Shutterstock/pixinoo

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The world’s effort to address climate change is one of the greatest challenges of our lifetimes. Success will require not just greater commitment and resources but creativity and flexibility to consider all tools available—and nuclear energy is one of them. It has an important role to play in the transition to net-zero emissions by 2050.

Nuclear energy generation currently provides one tenth of global electricity without producing carbon dioxide emissions. With 444 nuclear reactors operating across 30 countries, nuclear energy is the largest source of low-carbon electricity in OECD economies, and the second largest in the world after hydropower.

NEA analysis of over 90 pathways to net-zero emissions considered by the United Nations Intergovernmental Panel on Climate Change reveals that to limit global warming to no more than 1.5°C, installed nuclear energy capacity must triple to 1,160 gigawatts by 2050. The world is not on track to meet these targets. Even with the about 50 nuclear energy reactors now under construction around the world and the 100 planned, global nuclear energy capacity will remain roughly constant as older reactors are retired.

One key advantage that the nuclear sector has is that it is an established industry with proven technologies and supply chains. Nuclear energy already displaces 1.6 gigatonnes of carbon dioxide emissions annually. Through refurbishments and long-term operation of existing reactors, the nuclear sector can continue displacing carbon dioxide for decades to come: up to 50 gigatonnes of cumulative carbon emissions between 2020 and 2050.  

There is also significant potential for new builds of large-scale nuclear energy reactors, which could displace 23 gigatonnes of emissions between 2020 and 2050 by replacing fossil power generation. This includes replacing coal power, which is among the most intensive emitters of carbon dioxide but is particularly widespread in developing countries, where demand for energy is forecast to grow quickly as more parts of their economies link up to the electricity grid. Currently, non-OECD countries China and India account for the biggest shares of such new projects.

As a key pillar of global decarbonisation strategies, nuclear energy would also save money: meeting the Paris targets without nuclear energy would cost the world an estimated USD 1.6 trillion more, according to the International Energy Agency.

But the nuclear sector can also play a much larger role. As countries ramp up other types of carbon-free energy production, such as solar or wind, nuclear power can serve as baseload that backs up renewables and guarantees electricity supply is constant, reliable and dispatchable. The importance of this has become obvious from the recent experience of some countries that have suffered power outages or surges in energy prices. Where nuclear facilities are being phased out, governments have had to resort to restarting fossil fuel-powered plants—including coal—to ensure a constant electricity supply, taking a direct step backwards in the fight to reduce carbon emissions and pollution.

A wave of near-term innovation in small modular reactors, meanwhile, is opening new applications for nuclear energy and opportunities to further move to net-zero emissions in the global economy. Small modular reactors, the first of which will be on the market in the next few years, could displace 15 gigatonnes of emissions between 2020 and 2050. This could include generating power on-grid and off-grid, supplying power for desalination, providing low-carbon heat for heavy industries like steel production and other hard-to-abate sectors, and producing hydrogen and other synthetic fuels to help eliminate emissions in the transportation sector.

Success will require regulatory frameworks that enable innovation. Governments should also invest to accelerate nuclear energy deployment, and encourage further investments from private investors by including nuclear energy in the scope of climate and development financing, classifying it as an environmentally sustainable source and making it part of ESG financing frameworks.

COP26 is an important milestone on the road to net-zero emissions. In many multinational events, politics trumps science and nuclear energy is not included in the discourse, creating significant gaps in the dialogue. This dynamic is deeply problematic. Nuclear energy must be included alongside all other options in discussions about energy transition in order to maintain the integrity of the policy dialogue. While policy makers may take different values-based decisions on the role of nuclear energy in their respective national contexts, the analyses and assessments that inform the choices must be complete and evidence-based to ensure that the complex trade-offs between options can be accurately understood.

It is important that the discussions at COP26 be inclusive, and honest about the imperative to use all available non-emitting energy options to meet the challenge of the times.

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Read the NEA Policy Brief: System Costs of Electricity

Read the NEA Policy Brief: System Costs of Electricity

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William D. Magwood

Director-General, Nuclear Energy Agency

Mr Magwood took up his duties as Director-General of the Nuclear Energy Agency (NEA) on 1 September 2014. He has extensive experience in both the regulatory and developmental aspects 
of nuclear energy, including at the international level.
From 2010 to 2014, he served as one of the five Commissioners appointed by the US President and confirmed by the US Senate to the US Nuclear Regulatory Commission (NRC). While a commissioner, he advocated the importance of nuclear regulatory independence and the necessity of maintaining strong, credible and technically sound nuclear regulation in the United States and all countries that use nuclear power.

Prior to his appointment at the NRC, from 2005 to 2010 he provided independent strategic and policy advice to US and international clients on energy, environment, education, and technology policy issues. From 1998 to 2005, Mr Magwood was Director of the US Government’s civilian nuclear energy programme at the US Department of Energy (DOE). During his tenure, he established the Idaho National Laboratory; created activities that reversed the decline of US nuclear technology 
education; and launched important initiatives such as the Generation IV International Forum (GIF) and the US “Nuclear Power 2010,” which helped restart nuclear plant construction in the United States. He was also actively involved in the work of the NEA, serving as a Steering Committee 
Bureau member from 1999 to 2005, including a term as Chair of the Steering Committee from 2004 to 2005.

Prior to his experience at the DOE, Mr Magwood managed electric utility research and nuclear policy programmes at the Edison Electric Institute in Washington, DC, and was a scientist at Westinghouse Electric Corporation in Pittsburgh, Pennsylvania. Mr Magwood, a US national, holds Bachelor degrees in Physics and English from Carnegie Mellon University and a Master of Fine Arts from the University of Pittsburgh.