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Small Modular Reactors

New technologies, like Small Modular Reactors are making significant progress and could play an important role in the integrated energy systems by providing low-carbon electricity and/or heat from a relatively small footprint.

Even if most new nuclear power plants planned - or currently under construction - are large, light water-cooled units, Small Modular Reactors (SMRs) represent a complementary solution to such power plants. SMRs would contribute to the decarbonisation of hard to decarbonise sectors such as transport, chemical and steel industry, and district heating.

SMRs can vary in size from less than 10 megawatts electric (MWe) up to 300 MWe and can use a range of possible coolants including light water, liquid metal or molten salt, depending on the technology. SMR is the generic term to name such kinds of reactors, but the ones based on non-light water technology are also often called advanced modular reactors (AMRs). They all use nuclear fission reactions to generate heat that can be used directly or for generating electricity. SMRs comprise the latest technological features and safety advantages and many companies, and start-ups are looking into SMR projects.

The Commission’s priority is that the new SMRs/AMRs designs under development ensure that nuclear energy is used only with the highest standards of safety, radiation protection for workers and citizens, responsible management of radioactive waste and spent fuel, and a reliable non-proliferation regime, which ensures that nuclear material is not diverted from its intended use.

Benefits and challenges

SMRs present several potential benefits, ranging from improved safety features, such as passive safety systems, better financing options due to reduced construction schedules, lower investment needs, fewer components and smaller plant footprints per unit. For EU countries which choose to include nuclear in their energy mix, SMRs could also be a promising option for replacing old coal power plants and complementing as well as facilitating the increasing penetration of renewables. They can be flexibly used for district heating, desalination, generation of process heat for energy-intensive industries and production of hydrogen.

More facts on SMRs

At the same time, challenges still exist in validating the business case for SMRs, assuring predictable and streamlined licensing processes and frameworks, developing global supply chains to ensure profitability, identifying suitable nuclear sites and achieving a transparent dialogue model between the concerned stakeholders.

EU leadership and strategic independence for SMRs

On 29 June 2021, the European Commission organised the first EU workshop on small modular reactors. EU policymakers and industrial, regulatory and financial actors debated industrial cooperation, regulatory and licencing processes, financing as well as research and development support – all needed for a sustainable SMR deployment and secure supply chain to support decarbonisation.

European SMR Industrial Alliance 

One of the most important outcomes of the 2021 workshop was a proposal for the creation of a ‘European SMR Partnership’. It was suggested to take the form of a collaboration scheme involving industry stakeholders, research and technological organisations, interested customers (that is utilities and even EU countries), European regulators and the European Commission.

A preparatory work to identify enabling conditions and constraints towards safe design, construction and operation of SMRs in Europe in the next decade and beyond was done in the frame of the European SMR pre-Partnership. The work was led by a Steering Committee, supported by 5 work streams, essential for the SMR technology outlook, and safe deployment in the EU

  • market integration and deployment
  • licensing
  • financing and partnership
  • supply chain adaptation
  • innovation, research and development

The Communication on the EU’s 2040 climate targets, adopted on 6 February 2024, recognised SMRs as contributors to reaching the climate targets and announced the launch of the European SMR Industrial Alliance. The call for membership was published on 9 February 2024.

Research and training on SMRs

The Commission has also actively supported SMR safety research via the Euratom Research and Training Programme, with an EU contribution of EUR 16 million. New projects for SMRs and advanced modular reactors, with a total budget of EUR 27 million will complement this action already in 2023.

The declaration on EU small modular reactors, signed on 4 April 2023 by the Commissioner for Innovation, Research, Culture, Education and Youth, Mariya Gabriel and EU nuclear stakeholders, was prepared as a follow-up to a high-level European nuclear roundtable, held in March 2022. It confirms the EU’s intention to continue to lead research, innovation, education and training for the safety of European SMRs.

SMRs at international level

The EU and the United States share a rich history of mutually beneficial cooperation on nuclear energy and an EU-US high-level forum on SMRs was organised in Brussels in 2019 to examine the challenges and opportunities associated with using SMR technologies, as part of the future energy systems.

To ensure coherence and complementarity of the efforts, the Commission is also maintaining close links with the new IAEA ‘Nuclear Harmonisation and Standardisation Initiative (NHSI)’ and with other relevant initiatives at the level of the OECD-NEA.

Interest in SMRs is growing at international level in the context of discussions about moving to net-zero greenhouse gas emissions. The below list includes links to recent SMR publications and platforms.


17 MARCH 2023
Annex: Euratom Research and Training Programme - Work Programme 2023-2025
(1.26 MB - PDF)