How Are Rolls-Royce SMR & Amentum Delivering SMRs in Europe?

While Rolls-Royce is best known for its luxury vehicles, the company has also been one of the UK's leading nuclear energy equipment manufacturers since 1958, when it became the sole supplier of nuclear reactors for the Royal Navy’s submarines.

In 2025, the British engineering firm was commissioned by the UK Government to construct a series of small modular reactors (SMRs) in North Wales.

Around the same time, it was contracted by Czech energy giant ČEZ for a nuclear project in the Temelín region, close to the Austrian border. Although these ventures have been in the pipeline for some time, details surrounding their development are only now beginning to surface.

To help deliver its SMR projects, Rolls-Royce has partnered with US-based Amentum, a global leader in advanced engineering. The American firm has been entrusted with both the strategic planning and day-to-day execution of the SMR programme.

First deployments in two markets

In the UK, Rolls-Royce’s SMR facility will be based at Wylfa on Anglesey, Wales. The three planned SMRs are expected to generate up to 1.5GW of low-carbon energy and create over 8,000 long-term jobs. Great British Energy selected Rolls-Royce for the initiative in July 2025, marking the construction of the UK's first-ever small modular reactors.

Meanwhile, in the Czech Republic, Rolls-Royce’s contract with ČEZ was finalised in October 2024. The project will deliver up to 3GW of power generation capacity, following ČEZ’s acquisition of a 20% stake in Rolls-Royce’s SMR business early last year.

Rolls-Royce’s role in nuclear energy

So how does Rolls-Royce’s SMR technology actually work?

The company’s design is a 470MWe pressurised water reactor capable of generating continuous baseload power for at least 60 years.

Roughly 90% of each unit is built under factory conditions, with reactor modules measuring about 16 metres long and four metres wide.

This modular approach means most on-site work is limited to assembling pre-fabricated and pre-tested components — a strategy Rolls-Royce says reduces project risk and shortens construction timelines compared to traditional nuclear builds.

Why Amentum is the ideal partner

Amentum brings extensive nuclear project experience to the partnership.

The company is currently involved in constructing Hinkley Point C and Sizewell C, the first major nuclear facilities built in the UK in decades.

It also oversaw the decommissioning of Cumbria’s Sellafield site, which ceased operations in 2003, and has participated in numerous nuclear projects across Europe — making it a natural fit for Rolls-Royce’s expansion into the Czech Republic.

The leadership behind the partnership

John Heller, CEO of Amentum says: "The Amentum Rolls-Royce SMR collaboration advances the deployment of this transformational technology, a critical enabler in strengthening energy security in the UK and continental Europe."

Loren Jones, who is SVP and Head of Amentum's international Energy and Environment business is excited about both the projects themselves and the jobs they will create.

"Amentum will support the deployment of a fleet of Rolls-Royce SMRs, contributing to our growth and our plan to create new jobs in the UK over the next four years," he explains.

On the other side of the deal, Rolls-Royce's SMR executives are feeling energised by the collaboration.

"By working with Amentum, an established and experienced global nuclear leader, we are combining our skills to build a powerful team that will enable successful delivery on our order commitments in multiple markets," says Chris Cholerton, CEO of Rolls-Royce SMR.

"This partnership plays directly to our strengths – ours in advanced manufacturing and engineering, and theirs in program and construction excellence," he adds.

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A blossoming relationship

This isn’t the first collaboration between Rolls-Royce and Amentum. The two companies first joined forces in 2016 as part of a consortium developing concepts for modular power stations. Now, as Rolls-Royce’s project delivery partner, Amentum will work alongside Turner & Townsend, Hochtief, Mace Consult and Unipart.

This deepening relationship also reinforces Amentum’s position in the UK’s clean energy transition.

The company continues to support nuclear facility maintenance through a Lifetime Enterprise Agreement with EDF.

As Ruth Todd, Operations & Supply Chain Director at Rolls-Royce SMR, explains: “This partnership supplements our existing capabilities with specialist expertise, geographical reach and provides access to the breadth of Amentum's wider supply chain.”