Energy demand is rapidly increasing, driven by the rise of electrified transport and emerging technologies like AI and a push for decarbonization to advance climate goals. Power grids globally must grow to meet the increased loads while maintaining reliability, resiliency and affordability. A renewed wave of technological innovation in nuclear energy is under way to address demands for green power options. Generation III reactors are primarily pressurized water-cooled reactors and incorporate accident-tolerant fuels and improved safety systems. In parallel, Generation IV reactors propose alternative cooling fluids, such as molten metals, molten salts or gases like helium. These alternative coolants operate at higher temperatures and lower pressures, simplify reactor designs, improve safety and reduce costs. There is also a growing trend towards reducing the scale of power plants, with designs allowing key components to be manufactured in a factory and then transported to site. These small modular reactors (SMRs) typically cover about one-third of the generating capacity of traditional nuclear power reactors.32 Deploying multiple identical SMRs to achieve power outputs eliminates the high costs and long design cycles of a bespoke reactor, making SMRs attractive for distributed power generation. Nations are dedicating substantial public funds to support large-scale SMRs and alternative cooling designs.33 These investments extend to new fuel fabrication facilities and enrichment plants, making deployment possible by the end of this decade.34 Currently, only a few countries are heavily investing in large reactors outside of Russia and China. Most notably, South Korea has 26 nuclear reactors, accounting for one-third of the country’s electricity,35 and the United Arab Emirates’ Clean Energy Strategy involves investment of $163 billion by 2050 to have half of its electricity come from nuclear and renewables.36 Two European Pressurised Reactors (EPRs) and two AP1000s in the US37 have also been brought online in recent years. In the SMR arena, Russia and China already have operational plants, while Western countries are rapidly advancing in design, construction and regulatory frameworks to establish a competitive industry. In November 2024, in collaboration with Accenture, the World Economic Forum published A Collaborative Framework for Accelerating Advanced Nuclear and Small Modular Reactor Deployment , which serves as a tool to align stakeholders on key actions required to achieve the deployment of this key technology. While the immediate future of nuclear deployment lies in fission reactors, the long-term goal for many is nuclear fusion, or the process of fusing hydrogen atoms to form helium, which releases enormous amounts of energy – the same mechanism that powers the sun. Although no net power gain has yet been achieved, there is high confidence that within one to two decades, this near-limitless source of clean energy will mature. This shift towards advanced nuclear technologies, combined with enhanced renewable energy strategies and improved energy storage solutions, underscores the global urgency of transitioning away from fossil fuels and securing a sustainable, zero-carbon future.Doug Arent Executive Director, National Renewable Energy Laboratory Foundation Karen Hallberg Principal Researcher, Bariloche Atomic Center (CONICET)Bernard Meyerson Chief Innovation Officer Emeritus, IBM Boxed Icons Launch community-focused safety demonstrations – Develop educational programmes showcasing the enhanced safety features of new nuclear designs through transparent demonstrations and community engagement.Ecosystem readiness map Boxed Icons Accelerate prototype testing – Fund comprehensive testing programmes for next-generation nuclear designs, particularly gas-cooled reactors, to validate safety systems and operational efficiency under various conditions.KEY ACTIONS TO ACHIEVE SCALE TechnologicalSocial EconomicEnvironmentalPolicy Image: Advanced nuclear technologies support rising clean energy demands and decarbonization goals. Credit: Midjourney and Studio Miko. Prompt (abbreviated): “Nuclear reaction creating a swirl of energy.” Read more: For more expert analysis, visit the advanced nuclear technologies transformation map. Authored by: Sergei Dudarev, Wenxi Tian. Top 10 Emerging Technologies of 2025 16