Policy paper

Advanced Nuclear Technologies

Updated 4 February 2026

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New nuclear

The Department for Energy Security and Net Zero is at the heart of the government’s agenda, leading one of the Prime Minister’s 5 national missions, to make Britain a clean energy superpower with zero carbon electricity by 2030, and accelerating our journey to net zero. The government will ensure the long-term security of the nuclear sector by seeking to extend the lifetime of existing plants and also focus on new nuclear power. To achieve our goal of clean power by 2030, we need homegrown, clean energy power sources including nuclear, wind, solar batteries, tidal stream, hydrogen, carbon capture, and nuclear has a pivotal role to play in the future age of clean electricity.

Nuclear energy is central to this mission. It provides the stable, low-carbon baseload that keeps the lights on and supports our economy. That is why we have launched a new golden age of nuclear, committing £17 billion to the most ambitious programme of new plants for a generation, and revitalizing our communities as we get Britain building again.

From Sizewell C in Suffolk, which will power the equivalent of 6 million homes and provide 10,000 jobs and 1,500 apprenticeships at peak construction, to the newly announced Small Modular Reactors at Wylfa on Anglesey, the most significant industrial investment in North Wales for a generation. Building on these large-scale projects, the next frontier lies in advanced nuclear technologies, these innovative designs offer flexibility with their modular designs and additional uses.

Around the world, advanced nuclear is unlocking new markets, attracting billions in private investment, and creating high-value jobs in engineering, manufacturing, and research. For the UK, it means not only supporting our net zero ambitions but positioning ourselves as a global hub for new nuclear technology, an industry that will power homes, industries, and data-driven economies for decades to come.

What are Advanced Nuclear Technologies?

Advanced Nuclear Technologies (ANTs) is a collective term for the wide range of innovative nuclear reactor technologies under development in the nuclear sector. They are smaller in size, both in terms of power output and land footprint, than large gigawatt-scale reactors. Due to their smaller size and modularity, ANTs can be fabricated off site in factories then assembled on site potentially making construction quicker and less capital intensive. Offsite manufacturing reduces the local impact of construction and spreads the location of jobs. This allows skilled jobs to be created across different sectors, through the life cycle of nuclear and around the UK.

ANTs also have potential to tackle hard-to-abate emissions in sectors beyond electricity, by providing low carbon heat and power directly to energy-intensive industries. This could be a critical capability to achieve net zero.

Generally, Advanced Nuclear Technologies fall into one of 3 groups: 

  • Generation III water-cooled SMRs are fission reactors with power output less than ~500Mwe. They are similar to existing nuclear power station reactors but on a smaller scale. SMRs use standard, readily available 4% enriched uranium fuel. This fuel is also used in most commercial nuclear reactors around the world. The government uses the term SMRs to refer specifically to Generation III
  • Generation IV, and beyond, AMRs use novel cooling systems, novel fuels, and/or novel reactor physics to offer new functionality (such as industrial process heat) and potentially a step change reduction in costs. Many designs have the potential for a range of applications beyond low-carbon electricity generation, including the production of hydrogen and direct heat for industrial or domestic use. The government uses the term AMRs to refer specifically to Generation IV
  • Micro Modular Reactors (MMRs) are a sub-set of both SMRs and AMRs. MMRs are designed with much lower power output than other advanced reactors, typically producing no more than 30MW(e). They have potential for specialised niche applications that require smaller amounts of highly reliable energy, such as remote communities and data centres

Latest news

February 2026: Advanced Nuclear Framework for private projects

The Advanced Nuclear Framework for Privately Led Projects sets out how we will create the right policy environment for private sector investment in advanced civil nuclear projects. The Framework is designed to support the development, commercialisation, and deployment of innovative nuclear projects within the UK energy system.

The UK Advanced Nuclear Pipeline and Project Readiness Assessment process is to enable projects with strong plans to access early engagement and potential future support.

Introductory events

We are holding introductory events on the Framework and Pipeline guidance, including a question and answer session.

Please register your interest for one of the events (all identical):

If you have any questions about the Framework or guidance, or any feedback on the documents, please email our Advanced Nuclear Business Engagement Unit at: advancednuclear@energysecurity.gov.uk.

December 2025

November 2025

September 2025

UK-US deal on energy security announcement

The UK and US announced a package of commercial commitments that deepen civil nuclear cooperation and increase market access for both countries. Building on existing collaboration, including between Rolls-Royce and BWXT, new major commercial deals were announced:

  • X-Energy and Centrica: intention to develop up to 12 advanced modular reactors in Hartlepool, followed by a UK-wide programme targeting a 6GW fleet. According to the companies, the Hartlepool project could power up to 1.5 million homes and create up to 2,500 jobs; they estimate the overall programme could deliver at least £40 billion in economic value, with £12 billion focussed in the Northeast of England
  • Holtec, EDF and Tritax: plans to develop advanced data centres powered by small modular reactors at the former Cottam coal-fired power station in Nottinghamshire. Holtec estimates the project value at around £11 billion, with thousands of high-skilled construction jobs, and long-term roles in operations for the local community
  • Last Energy and DP World: plans to establish one of the world’s first micro modular nuclear power plants, backed by £80 million in private investment, to provide clean power for the expansion of DP World’s London Gateway port and business park
  • Urenco and Radiant: agreement worth around £4 million to supply high-assay low-enriched uranium (HALEU) fuel to the US market. Urenco is building an Advanced Fuels Facility in the UK co-funded with the UK Government and is exploring a similar facility in the US
  • TerraPower and KBR: plans to conduct studies and evaluate UK sites for Natrium advanced reactor deployment. According to the companies, each Natrium project could support around 1,600 construction jobs and 250 permanent roles, delivering firm, flexible nuclear power paired with gigawatt-scale energy storage

Read the full announcement: Golden age of nuclear delivers UK-US deal on energy security - GOV.UK

June 2025

Spending Review 2025

The Spending Review 2025 confirmed the government’s biggest investment in nuclear power for a generation, supporting energy security, clean power and high-quality jobs across the UK:

  • £14.2 billion for Sizewell C – the first state-backed nuclear power station since Sizewell B began construction in 1988
  • over £2.5 billion for SMRs with Rolls-Royce SMR selected as preferred bidder to partner with Great British Energy – Nuclear, subject to approvals
  • over £2.5 billion for nuclear fusion including support for the UK’s programme to design and build a prototype energy plant in Nottinghamshire
  • £13.9 billion capital for the Nuclear Decommissioning Authority to continue to keep former nuclear sites safe and secure while managing the UK’s nuclear legacy
  • Great British Energy and Great British Energy – Nuclear to invest more than £8.3 billion in home-grown clean power. GBE-N estimates that a project delivered under its SMR programme could support up to 3,000 skilled jobs and power up to 3 million homes
  • a new framework for privately led advanced nuclear projects

Great British Energy – Nuclear

Great British Energy – Nuclear (GBE-N), the government’s nuclear delivery body, is to drive forward the UK’s SMR programme, one of the first in Europe:

  • over £2.5 billion made available across the Spending Review period to enable the programme
  • GBE-N selected Rolls-Royce SMR as its preferred bidder to partner with to build the UK’s first SMRs, subject to government approvals and contract signature
  • Wylfa on Anglesey selected as the site for the UK’s first SMR, marking a major milestone in the government’s Clean Energy Superpower plan. With the aim of deploying to the grid in the mid-2030s, an SMR project delivered within the scope of the contract could provide up to 1.5GW of low carbon electricity, which would power the equivalent of up to 3 million of today’s homes while also supporting up to 3,000 jobs at peak construction

The Advanced Nuclear Framework

Announced in the Spending Review, the Advanced Nuclear Framework for privately led projects, published February 2026, sets out how government will create the enabling policy landscape for the private sector to initiate and deliver advanced nuclear projects:

  • Great British Energy Nuclear will have a role in assessing proposals
  • the National Wealth Fund will explore potential investment opportunities
  • DESNZ will explore revenue support for viable projects

The Framework:

  • introduces the UK Advanced Nuclear Pipeline and the Project Readiness Assessment process, enabling projects with strong plans to access early engagement and potential future support
  • outlines the UK’s enabling conditions, from regulation and planning to skills, supply chain, and fuel, ensuring that private projects have the foundations to succeed

Consultation on alternative routes to market for new nuclear projects

The Alternative Routes to Market for New Nuclear Projects Consultation ran for 13 weeks in 2024. It explored the steps government could take to enable different routes to market for Advanced Nuclear Technologies, the potential wider roles of nuclear energy beyond electricity generation and how government can support the private sector to bring forward new nuclear projects.

Funding and support packages: Future Nuclear Enabling Fund (FNEF)

The Future Nuclear Enabling Fund (FNEF) provides up to £67 million of targeted support for new nuclear development. It aims to help industry reduce project risks, so they are better positioned for future investment decisions. The funding will accelerate advanced nuclear business development in the UK and support advanced nuclear designs to enter UK regulation.

Three successful grant recipients were identified under the FNEF:

  • up to £33.6 million awarded to GE-Hitachi Nuclear Energy to support development of their BWRX-300 SMR design. GDA Step 2 of the GE Vernova Hitachi SMR: fundamental assessment is completed
  • up to £30.05 million awarded to Holtec Britain Limited to support development of their SMR-300 design
  • up to £3.34 million awarded to Cavendish Nuclear. Cavendish Nuclear partnered with X-energy to develop the Xe-100 Advanced Modular Reactor (AMR) toward UK deployment

Regulation

The UK has one of the safest and most robust nuclear regulatory regimes in the world, and all nuclear operators are answerable to our independent regulators, the Office for Nuclear Regulation, and national environmental regulators such as the Environment Agency.

Nuclear Regulatory Taskforce

April 2025: government launched an independent Nuclear Regulatory Taskforce to help streamline regulatory practices, covering civil and defence nuclear. The Taskforce considered changes to legislation, the scope of regulators, pro-growth outcomes, the application of regulation, and guidance for new nuclear technologies. It also explored better international alignment so reactor designs approved abroad could be green lit more quickly, minimising expensive changes.

November 2025: the Taskforce published its final report Nuclear Regulatory Review 2025. Its findings made clear that radical change is needed and that government should act with urgency to deliver that change. The Prime Minister endorsed the approach and accepted the principle of all recommendations. Government has committed to complete implementation within 2 years, subject to legislative timelines on elements requiring primary legislation.

Early regulatory engagement process

In June 2024, the Office for Nuclear Regulation, along with the Environment Agency and Natural Resources Wales launched guidance on an Early Regulatory Engagement Process for nuclear regulation. This process is available to any party requesting early engagement on a proposed reactor deployment in Great Britain, including reactor technology vendors, developers and aspirant licence / permit holders.

The guidance enables applicants to develop their understanding of regulatory processes and expectations early on in their projects and provides a new way for interested parties to engage with regulators. There are 3 approaches to early engagement:

  • one-day engagement
  • process and technical engagements
  • preliminary design review

Generic Design Assessment (GDA)

The Office for Nuclear Regulation and the Environment Agency published guidance on the Modernised Generic Design Assessment (GDA) process in October 2019:

The Regulators modernised the GDA process in 2020, considering lessons learned from previous GDAs and recognising the emergence of Advanced Nuclear Technologies. This introduced new flexibilities into the GDA process that can enable assessment of innovative Advanced Nuclear Technologies.

The Generic Design Assessment allows the UK’s independent nuclear regulators to assess the safety, security, and environmental implications of new reactor designs and to provide the confidence that these new designs are capable of meeting the UK’s statutory regulatory requirements.

The GDA Entry process is an open and ongoing process, with a standing invitation for advanced nuclear companies to apply when they believe they are ready to do so.

The department maintains a public register of requesting parties whose applications are being assessed against the GDA Entry criteria. The department is currently assessing:

  • TerraPower, LLC 

Details of GDAs currently being assessed by the regulators are also available on the Office for Nuclear Regulation website.

Apply to enter to GDA process

International

International collaboration is a fundamental part of the government’s policy to successfully realise the opportunities of Advanced Nuclear Technologies.

The UK is a founding member of the Generation IV International Forum (GIF), created as a cooperative international endeavour seeking to coordinate research and development on fourth generation nuclear systems.

The UK is also a member of the Clean Energy Ministerial (CEM), a global forum focused on the transition to global clean energy.

At COP29 the UK and US signed a new multilateral research agreement which came into force 1 March 2025. The UK will take a leading role in the forum, which aims to support information-sharing on advanced nuclear technologies and make them available for use in industry by 2030. This will support the commitment made at COP28 to triple nuclear energy capacity globally by 2050, with 31 countries signed up including the US and UK. 

The Nuclear Innovation and Research Advisory Board

The Nuclear Innovation and Research Advisory Board (NIRAB) was convened by government to provide advice on nuclear research and innovation in the UK. Their NIRAB III Summary Report provides an overview of the important strategic national initiatives, programmes and consultations on which NIRAB has provided guidance and advice in its third 3-year term (2021-2024), including recommendations to support the deployment of Advanced Nuclear Technologies.

DESNZ Public Attitudes Tracker

The DESNZ Public Attitudes Tracker is a triannual survey that collects data on public awareness, behaviours and attitudes relating to the department’s policy areas.

A report on a public dialogue was published to explore views on how and where advanced nuclear technologies might be used, this was published in 2019.

Publications

Contact us

ANPD@energysecurity.gov.uk

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