Nuclear energy is experiencing a revival in fortunes with investment rising in both traditional large-scale plants and new designs, including small modular reactors (SMRs), and capacity set to increase by at least one-third to 2035 – and potentially by as much as 70%, according to a new report.

The International Energy Agency’s (IEA) World Energy Outlook 2025 says more than 40 countries now include nuclear energy in their strategies and are taking steps to develop new projects.

The report says that after more than two decades of stagnation, installed nuclear capacity could expand by as such as 70% by 2035 in its Net Zero Emissions by 2050 scenario, which maps out a pathway to achieve specific energy and climate-related goals. Under less ambitious scenarios nuclear capacity is forecast to increase by one third.