The Commission recognises the potential contribution of small modular reactors to achieving the objectives of the Clean Industrial Deal (2025).
While the Commission remains technology-neutral and leaves it to EU countries to determine their own energy mix, several emerging low-carbon technologies, can contribute to this ambition. Small modular reactors (SMRs) are one of these technologies.
What are SMRs?
SMRs are small nuclear reactors that can vary in size from around 20 megawatts electric (MWe) up to 300 MWe and produce up to 7.2 million kWh per day. They can use a range of possible coolants, including light water, liquid metal or molten salt, depending on the technology.
SMRs incorporate the latest technological and safety features, and many companies and start-ups are exploring SMR projects.
By comparison, large-size nuclear power plants have outputs of over 1000 MWe and can produce 24 million kWh per day.
SMR is the generic term for these types of reactors, while those using non-light water technology are often called advanced modular reactors (AMRs). They all use nuclear fission reactions to generate heat that can be used directly or to produce electricity.
What are the advantages?
The economics and business case of SMRs are different from traditional nuclear power plants. SMRs have a range of advantages
Besides contributing to the decarbonisation of the EU energy mix, SMRs can also help ensure the stability of the electric grid in a system with a higher share of renewables and increasing electricity demand.
As they are smaller in size, power output and capacity, they need less space and cooling water, and offer greater flexibility for site selection than large nuclear plants.
They are modular and can be produced in series, which allows for production cost efficiency through economies of scale.
Since their systems and components can be factory-assembled, they can be transported as modules or even as whole units to a location, reducing installation costs.
SMRs are well suited to replace fossil fuel-fired plants, allowing communities to retain high-skilled job opportunities in areas affected by plant closures.
They are well suited for integration into energy hubs in combination with other energy sources and vectors, like renewables and hydrogen.
They are adapted to supply electricity and are also capable of supplying heat for industrial applications, district heating, and hydrogen production.
SMRs are harnessing the operating experience from traditional large reactors, as well as from small-scale reactors used in nuclear submarines and other nuclear-powered vessels, such as icebreakers.
They further incorporate passive (and inherent) safety features, simpler designs, and higher coolant fractions. Together, these characteristics significantly extend the time available for operators to respond to potential incidents or accidents.
SMR safety principles mostly rely on simple phenomena, such as natural circulation to cool the reactor core, even during incidents or accidents that require little or no operator intervention to bring the reactor to a safe state.
These passive safety systems also allow the elimination of a range of components, such as valves, safety grade pumps, pipes and cables, thereby reducing the risk of their failure.
Global action on SMRs
Globally, there are more than 120 SMR designs at different stages of development.
While countries such as the U.S., UK, Canada, Japan, and South Korea are actively developing their own designs, Russia and China connected their first SMRs to the grid in 2019 and 2021, respectively.
The recent energy crisis, exacerbated by Russia’s invasion of Ukraine, demonstrated the importance of EU strategic energy independence and bolstering Europe’s ambition to lead in innovative energy technologies such as SMRs.
The EU is supporting research and development activities on SMRs under the Euratom Research and Training Programme (2026-2027).
The programme focuses on nuclear safety, security, safeguards, radiation protection and radioactive waste management, with a strong emphasis on developing nuclear-related skills.
To ensure the successful deployment of the first SMR projects by the early 2030s and strengthen Europe’s position in the global market, the Commission launched a European SMR Industrial Alliance in February 2024 and will publish a SMR strategy in March 2026.
