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Small Modular Reactors explained

The Commission recognises the potential contribution of Small Modular Reactors to achieving the energy and climate objectives of the EU Green Deal, as reflected in its recommendation for the 2040 emission reduction targets.

While the Commission remains technology neutral, and it is up to EU countries to determine their own energy mix, there are a number of emerging low-carbon technologies, which can play a role in this ambition. Small Modular Reactors (SMRs) are one of these technologies.

What are SMRs?

SMRs are defined as small nuclear reactors with a maximum output of 300 Megawatt electric (MWe) and can produce 7 200 000 kWh per day. By comparison, large-size nuclear power plants have an output of over 1000 MWe and can produce 24 000 000 kWh per day.

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 theEU energy mix, SMRs can help ensuring 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 less cooling water, but 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.

As their systems and components can be factory-assembled, they can be transported as modules or even whole units to a location, reducing installation costs.

SMRs are well suited to replace fossil fuels-fired plants, allowing to retain high-skilled job opportunities in areas affected by the closures of such plants.

They are well suited to be integrated in energy hubs in combination with other sources of energy and energy vectors, like renewables and hydrogen.

They are adapted to supply electricity and additionally capable to supply heat for industrial applications, district heating, as well as for production of hydrogen.

What about safety?

SMRs are harnessing the operating experience from traditional large reactors, as well as the use of small-scale reactors in nuclear submarines and other nuclear-powered vessels, such as icebreakers.

SMRs have passive (inherent) safety systems, with a simpler design, a reactor core with lower core power and larger fractions of coolant. These altogether increase significantly the time allowed for operators to react in case of incidents or accidents.

SMRs safety principles mostly rely on simple phenomena like natural circulation for the cooling of the reactor core, even during incident or accident situations requiring very limited, or even no operators’ actions to bring the reactor to a safe state in case of need.

These passive safety systems also allow elimination of a range of components, valves, safety grade pumps, pipes and cables limiting de facto the risk of their failure.

EU action on SMRs

  1. 6 February 2024

    The Communication “Securing our future. Europe’s 2040 climate target and path to climate neutrality by 2050 building a sustainable, just and prosperous society” recognises SMRs as contributors to the 2040 climate targets, and announces the launch to come of the European Industrial Alliance on SMRs.

  2. 6 December 2023

    The European Parliament adopts a report on SMRs, recognising the potential role of SMRs as a promising technology to promote the energy transition in Europe.

  3. 7 November 2023

    EU Commissioner for Energy, Kadri Simson, announced the intention “to establish an SMR Industrial Alliance in the earliest possible time frame”.

  4. 6 November 2023

    At the European Nuclear Energy Forum, Ministers from 12 EU countries and industry representatives call for more collaborative efforts initiated by the SMRs pre-partnership to speed up the development of SMRs.

  5. 4 April 2023

    Declaration on EU SMR 2030, signed by the European Commission and nuclear stakeholders.

  6. 19 March 2023

    The Commission's Net Zero Industry Act (NZIA) proposes to classify SMR technologies as net-zero technologies