Nuclear reactors worldwide generated 2,702 TWh of electricity in 2025, beating the previous year's record of 2,667 TWh, according to the World Nuclear Outlook Report, which also calculates that if all national nuclear targets were achieved, total capacity would more than triple by 2050.
(Image: WNA)The World Nuclear Association report includes an assessment of progress towards the widely-shared ambition - which 38 countries have signed up to - for a tripling of global nuclear energy capacity by 2050. It also sets out a series of policy recommendations.
Focusing on the existing fleet, the report notes that there has been a recent increase in construction starts, as shown by the chart below, which shows how it has fluctuated over the past 75 years.
(Image: WNA)
It also finds that the reliability of nuclear energy plants remains high across the global fleet and across the life of reactors, even as individual units age. The average capacity factor was 83.7% in 2025 (a capacity factor of 100% would be if a unit generated electricity 24 hours a day 365 days a year).
The capacity factor rises as the age of reactors passes 50 years (Image: WNA)
Looking ahead at the prospects for new nuclear capacity, the report projects that it could reach 1,457 GWe by 2050 if all national targets and goals are achieved and the existing fleet continues to operate. With current operating capacity being 423 GWe, that projected figure would be 200 GWe more than a tripling of the current levels.
New capacity under construction increased to 82 GWe, with eleven reactors starting construction in 2025. The combined total of planned, proposed and potential capacity increased to 416 GWe, reducing the gap between actual projects and government targets, although around 550 GW of proposed capacity by 2050 has yet to be translated into specific projects.
(Image: WNA)
As to where the new capacity would be located, the report found that the largest share of the new capacity would come from the established users of nuclear energy - the USA, China, France, Russia and India.
(Image: WNA)
World Nuclear Association Director General Sama Bilbao y León, said: "This is an extraordinary moment for nuclear energy. Reflecting on another year of record performance, and looking ahead to a future of record ambition, governments are clear: they need much more nuclear energy to address the interconnected challenges of energy security, affordability, competitiveness and climate goals.
"But ambition alone will not deliver 24/7 clean energy. That's why the Association has published recommendations that set the path towards tripling global nuclear energy capacity by 2050. We need to make full use of the existing fleet, complete reactors already under construction, capitalising on the acquired capabilities, commit to the next projects and move from individual projects to sustained programmes of deployment."
As well as reviewing the progress towards individual countries' targets, the report includes a series of policy recommendations for governments, industry, financiers and regulators.
These range from "establishing durable policy and investment frameworks, streamlining regulation and strengthening supply chains, to building the workforce, supporting proven reactor deployment and creating the programme-based delivery models needed". It also highlights that maintaining and extending the existing fleet is the fastest and most cost-effective ways to secure low-carbon electricity.According to World Nuclear Association, "For the rest of this decade, the focus must be on turning national ambitions into credible project pipelines, supported by the institutions, investment, people and industrial capacity needed to deliver them." Fresh record set for nuclear generation in 2025
