UK and US Set to Announce Fusion Supercomputing Partnership at London Summit
The UKAEA-Princeton deal expected Monday adds transatlantic computing capacity to a programme already backed by £2.5 billion in UK public investment.
The UK and United States are expected to announce fusion energy agreements at a summit in London on Monday (2026-09-14), with the lead item a new supercomputing partnership between the UK Atomic Energy Authority and Princeton Plasma Physics Laboratory.6
The summit arrives four months after the UK government unveiled what it described as a "record" £2.5 billion investment in fusion technology in May 2026, alongside a Fusion Investment Prospectus estimating the global market could eventually reach between £3 trillion and £12 trillion. Energy minister Michael Shanks said the sector could support more than 10,000 UK jobs by 2030, framing the investment as both an energy security and industrial policy initiative. That projection range spans an order of magnitude. No commercial fusion plant has yet operated anywhere in the world.6
Private capital has reached the sector at scale. Global private investment in fusion hit a record $4.48 billion in 2025, up 69% year-on-year according to the Fusion Industry Association, driven in large part by power demand from AI data centres and rising energy security concerns — two forces that have pushed long-horizon generation technologies back up the investor agenda.4
Commonwealth Fusion Systems closed an additional $1 billion round in July 2026 (2026-07-30). BloombergNEF lead nuclear analyst Chris Gadomski described the raise as "recognition that this is going to be something that's materially significant in the next decade."5
California-headquartered Pacific Fusion, founded in 2023, said on June 2 (2026-06-02) it had raised more than $1 billion led by General Catalyst. The company reported its pulsed power system had achieved peak output power above 440 gigawatts and peak voltage of approximately 1.1 megavolts, and said it remains on track to achieve net facility gain (where total facility energy output exceeds total energy input) by 2030.1
Within the UK, the programme spans several workstreams. UK Fusion Energy signed a £30 million contract with Dassault Systèmes on June 30 (2026-06-30) to build a digital twin of the UK's first prototype fusion plant using the 3DEXPERIENCE platform, combining UKFE's fusion expertise with Dassault's virtual modelling capability. Separately, the University of Birmingham's Electric Power Research Institute launched FURESHMA, a £2.63 million industry collaboration on fusion reactor shielding materials.3,6
Much of the UK's fusion cluster is concentrated around Oxford, Birmingham and Nottingham, a geography the government has targeted for research infrastructure investment. The UKAEA-Princeton computing partnership adds a transatlantic research dimension to that network.6
The small modular reactor sector offers a recent reference point. SMRs, advanced nuclear designs rated up to 300 MW(e) and roughly one-third of a conventional plant's capacity, attracted comparable institutional momentum in the early 2020s before supply chain problems and technical setbacks left commercial deployment timelines uncertain, according to OilPrice.com in June 2026 (2026-06-21). The US Department of Energy selected Tennessee Valley Authority and Holtec Government Services in December 2025 to support early SMR deployments in the United States, a process that still required sustained government backing to advance. Fusion's technical requirements are more demanding still.2
Pacific Fusion's 2030 target for net facility gain is the clearest near-term milestone in the sector. Even if reached, a commercial plant generating power to the grid involves a further round of engineering, regulatory and financing work that no fusion company has yet cleared.1