A £300m deal has been struck to support Rolls‑Royce small modular reactors at Wylfa. The contract names an Amentum/Cavendish Nuclear joint venture as Owner’s Engineer for the project.
Big-ticket technical oversight for first UK SMRs
Great British Energy – Nuclear (GBE‑N) has appointed a joint venture of Amentum and Cavendish Nuclear to serve as Owner’s Engineer for the deployment of Rolls‑Royce small modular reactors (SMRs) at Wylfa, on the island of Anglesey. The agreement is worth up to £300 million and can run for as long as 14 years, the parties said.
Litmus Nuclear, the joint venture, will provide independent assurance and technical advice covering design, safety, engineering, construction, and commissioning. That support is intended to help GBE‑N meet regulatory requirements and move the programme towards a final investment decision (FID) anticipated in 2029.
Amentum is a US‑headquartered company with a substantial UK presence; Loren Jones, senior vice president and head of Amentum's Energy & Environment‑International business, said the award recognises Amentum’s expertise and complements its work on other UK projects such as Hinkley Point C and Sizewell C. Cavendish Nuclear, part of Babcock International, will bring its construction and nuclear engineering capability; Mick Gornall, managing director of Cavendish Nuclear, described the appointment as a landmark role that offers assurance for the country’s first‑of‑a‑kind SMR programme.
What the Owner’s Engineer will actually do
The contract requires Litmus Nuclear to act as an independent assurance body for the Rolls‑Royce SMR programme. That means third‑party checks on design integrity, safety cases, construction quality and commissioning procedures — essentially a continuous technical audit to satisfy both GBE‑N and regulators.
Right now, most of the Rolls‑Royce SMR technology is designed to be factory built. Around 90% of each reactor will be constructed off‑site as modules roughly 16 metres by four metres, then transported and assembled on site, reducing on‑site activity and, the developers argue, cutting project risk and schedules.
The Rolls‑Royce design is a 470 MWe small pressurised water reactor intended to provide stable baseload power for at least 60 years. The modular approach is central to the business case: repeatable factory production should lower cost and improve predictability for future units, provided the first projects stay on time and on budget.
Why the deal matters to the UK
The contract is a visible step in the UK government’s push to revive a homegrown nuclear supply chain. GBE‑N — the state‑owned body formerly known as Great British Nuclear — named Rolls‑Royce SMR as the preferred technology for the country’s first SMR project in June 2025, and the government later chose Wylfa to host the initial units.
That political backing matters because SMRs require long lead times, regulatory approval and sustained public investment to reach the point where private capital will commit. Simon Roddy, chief executive of GBE‑N, said he was pleased to welcome Amentum and Cavendish Nuclear to the team and expects their expertise to help the project move with pace and determination.
The Owner’s Engineer’s job isn’t glamorous, but it’s essential. If Litmus Nuclear spots problems early, GBE-N can address them before costs get out of hand, which should help build investor confidence for the 2029 FID. If the checks fail, the programme could face delays or extra expense; there’s no mystery there.
Supply chain, jobs and regional impact
The Rolls‑Royce SMR programme has been building a network of suppliers across Europe and the UK. Earlier partnerships have included agreements with specialist firms such as Swedish company Studsvik for fuel testing and lifecycle services, and Yokogawa for control systems engineering — moves intended to broaden the technical base available to the programme.
Ruth Todd, operations and supply chain director at Rolls‑Royce SMR, said selecting world‑class suppliers and doing much of the work in the UK and Czech Republic would create jobs and boost skills in regions where plants are due to be built. Karl Thedéen, president and CEO of Studsvik, and Koji Nakaoka, executive vice‑president at Yokogawa’s energy division, have both emphasised the potential for wider European collaboration.
Local economic impact at Wylfa could be substantial if the project proceeds. The government has said the site could host three Rolls‑Royce SMRs initially, with potential to host up to eight units in total. That could translate into sustained construction activity over years and long‑term operational jobs afterwards — if the programme delivers.
Regulatory timeline and investment hurdles
Regulation is the other big factor. The Owner’s Engineer role includes making sure the design and build meet the standards regulators demand. If regulators are satisfied, the FID in 2029 becomes more likely; if not, developers will need to rework parts of the programme, pushing costs up.
Chris Cholerton, chief executive of Rolls‑Royce SMR, has framed the company’s role as central to a rollout across domestic and export markets. The design has drawn attention from utilities beyond the UK: ČEZ in the Czech Republic has selected Rolls‑Royce SMR for potential deployment, and the technology is in the running at other sites in Europe.
Selling a British SMR design abroad could help fund domestic development and back UK industrial policy. But export orders depend on timely delivery at home — a simple chain of cause and effect that the Owner’s Engineer is meant to protect.
Costs, risks and the long view
There’s a clear risk profile. Factory modularisation promises lower risk in principle, but the first full‑scale projects are often where unforeseen problems show up. Delays, supply‑chain shortages, or regulatory hurdles could push costs higher, and those rises would have to be borne by government or investors.
Loren Jones at Amentum framed the award as part of accelerating nuclear’s revival globally, while Mick Gornall at Cavendish said the role would help create long‑term, meaningful careers. Those are real effects if the programme sticks to schedule; they’re less real if it slips.
Basically, the contract buys GBE‑N independent technical muscle. It doesn’t solve every political or financial question, but it’s a step that the programme needed: an external check on engineering and safety as the UK attempts to restart a domestic nuclear industry after decades of limited new build.
That, in turn, feeds into wider government goals for secure, low‑carbon power and industrial growth in regions such as North Wales. The success or failure of the first SMRs will shape how quickly the UK can rely on modular nuclear plants as part of its energy mix.
International context
Rolls‑Royce SMR has been positioning itself internationally. The company signed memoranda and supplier deals with a range of organisations to shore up testing, control systems and lifecycle services — moves that suggest a deliberate strategy to build a pan‑European supply chain ahead of construction.
Those partnerships matter in two ways. First, they broaden technical capability for complex tasks like fuel qualification and control systems. Second, they create political and commercial ties that can translate into orders and finance from foreign governments and utilities, easing pressure on UK public funds.
Still, the immediate task for GBE‑N and its new Owner’s Engineer is execution at home: get the design proven, satisfy regulators, keep costs under control and reach a positive FID in 2029. Deliver that, and export opportunities become realistic; fail, and the programme risks lengthy delay.
Finally, the appointment of Litmus Nuclear is the latest sign that the Rolls‑Royce SMR project is moving from concept to construction readiness, with technical oversight now formalised and key suppliers already on board.
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Simon Roddy, chief executive of Great British Energy‑Nuclear, said: "I'm pleased to welcome Amentum and Cavendish Nuclear to the team. Their valuable expertise will be instrumental in assuring GBE‑N's project moves with pace and determination."
This article was created with AI assistance.
