Britain’s first nuclear-powered data centre eyed for Cottam site

Britain moved closer to hosting its first nuclear-powered data centre, planned for the Cottam site in Nottinghamshire’s Trent Valley, after Holtec International unveiled a proposed project with EDF and Tritax Management. The plan, estimated at about £11 billion, would use small modular reactors to power a data centre that could underpin the AI fuelled era and reduce reliance on fossil fuels. Officials have signaled the facility could be up and running within seven years, with reactors expected to be operational by 2032. The project is distinct from Rolls‑Royce’s SMR plans for the National Grid, which are slated to begin operating in the mid‑2030s.

The data centre market in the United Kingdom is expanding rapidly as artificial intelligence research and deployment require vast amounts of electricity and cooling. A single AI model training session can consume about 1.5 gigawatts of electricity — roughly enough to power 750,000 homes and nearly the output of the country’s 500 existing data centres, according to industry estimates. That energy draw, coupled with equally significant water needs for cooling, has concentrated attention on how the UK will scale infrastructure without compromising climate goals. Industry and government officials say nuclear energy, delivered through SMRs, could provide a steady, low-carbon backbone for AI infrastructure, though observers warn the scale of the demand remains a challenge for the electricity grid and water resources. The promoters of the Cottam project argue that a closed-loop cooling system would recirculate water, reducing fresh-water intake compared with traditional cooling.

The plan is part of a wider UK‑US technology push and comes amid a raft of technology deals totaling about £131 billion announced during President Donald Trump’s state visit. Holtec’s leadership outlined a path to establish a leadership position in advanced nuclear deployment tied to AI, with Dr. Rick Springman, head of Holtec’s clean energy unit, saying, “We will help the UK seize a leadership position in advanced nuclear deployment and the AI race.” Gareth Thomas, a UK-based director at Holtec, described the possibility of multiple SMRs at Cottam and a target completion date of 2032. He noted the Cottam reactors would be based on a design being developed for a site in Michigan and that unused electricity could be sold back to the National Grid to bolster resilience. Thomas also highlighted a back-up grid connection to ensure reliability if a significant event disrupts the reactors. The timescale, he added, depends on the Office for Nuclear Regulation aligning with the U.S. Nuclear Regulatory Commission to streamline approvals for new projects, potentially enabling major construction to begin in 2029, two years after a corresponding US decision for the Michigan project.

Critics, however, caution that SMRs are not yet proven at the scale required for a data centre network. Bhargav Srinivasa Desikan, author of recent reports on big tech and climate, called SMRs “unproven technology” and warned that the data centre may outpace reactor readiness, potentially stressing an already congested grid. He said, “Nuclear energy is notorious for going beyond the money they think they’ll spend and taking more time.” Gina Neff, deputy head of the Responsible AI campaign, insisted the “math has to be right” before expanding AI infrastructure, stressing concerns about power and water availability and trade-offs between AI capacity and climate goals. Neff added that long‑term job creation from data centres is often overstated and pointed to their environmental footprint.

Water resources and environmental concerns have shadowed data-centre expansion across the country. In July, Anglian Water objected to a planned data centre in Lincolnshire over water-use concerns, though the developer argued the site would employ a highly water‑efficient design. In February, the Royal Academy of Engineering urged tighter reporting on energy and water use by data centres and warned against excessive consumption of drinking water. The government says data centres face sustainability challenges and that measures to curb energy and water use are a priority.

The Cottam project sits on a site with a historically different energy profile. The Trent Valley’s coal-fired era has given way to ambitions for a modern, nuclear-enabled data corridor. Cottam’s location was chosen in part for its National Grid connection, and the plan envisions selling surplus electricity to the grid to help balance supply, including during peak AI training periods. The reactors are envisioned as a cluster designed to deliver about 1.5 GW, with the ability to support a data centre that could underpin AI, cloud computing and other digital services for years to come.

If approved, construction would proceed under a tight regulatory timetable that hinges on a coordinated approach between Britain’s ONR and the U.S. NRC. The schedule envisions major construction beginning around 2029, with completion of the first phase by 2032 and ongoing development potentially expanding capacity beyond 1.5 GW as additional SMRs are deployed on the site. The project’s backers say the approach would diversify the UK’s energy mix and provide a stable platform for AI workloads, while proponents emphasize the potential for large-scale job creation and technology leadership.

As with any large energy project, the plan faces a mix of policy, engineering and market questions. Proponents argue that data centres are central to the AI economy and that nuclear-powered, water-efficient SMRs could deliver reliable, low‑carbon power. Critics warn of the risks of embedding massive AI infrastructure without fully addressing grid constraints and water security, urging careful planning, transparency in energy and water accounting, and clear evidence that the benefits justify the environmental and financial costs. The government has signaled a willingness to pursue nuclear options as part of a broader strategy to expand AI capabilities, but observers say the path from announcement to operation will require significant regulatory endurance and public engagement.

The timeline remains provisional, and the project will depend on securing regulatory approvals, market conditions, and the ability to align UK and US oversight. If all goes to plan, Britain could place a first nuclear-powered data centre at Cottam in the vanguard of a new, nuclear-backed AI infrastructure era. The coming years will test whether SMRs can deliver the scale, reliability and environmental assurances demanded by industry, government and the public.