This nuclear energy roadmap has been prepared jointly by the IEA and the OECD Nuclear Energy Agency (NEA). It finds that one quarter (24%) of global electricity could be generated from nuclear power by 2050, assuming no major technological breakthroughs. This would make nuclear the single largest source of electricity in 2050, with a correspondingly significant contribution to cutting greenhouse gas emissions.Unlike most other low-carbon energy sources, nuclear energy is a mature technology that has been in use for more than 50 years. The latest designs for nuclear power plants build on this experience to offer enhanced safety and performance, and are ready for wider deployment over the next few years. Several countries are reactivating dormant nuclear programmes, while others are considering nuclear for the first time. China in particular is already embarking on a rapid nuclear expansion. In the longer term, there is great potential for new developments in nuclear energy technology to enhance nuclear’s role in a sustainable energy future.