Key Points
- Tokamak Energy reached 100 million degrees in its ST40 spherical tokamak in 2022, the first privately owned company to do so.
- A five-year, $52 million public-private partnership with the US Department of Energy and DESNZ is upgrading ST40 through 2026 under the name LEAPS.
- Nexeon completed a fundraise resulting in $170 million of total investment plus $50 million of related commercial investment — a combined raise the company described as over $200 million.
Oxfordshire's energy sector is anchored by two of the most closely watched private fusion and battery technology companies in the UK, both drawing significant transatlantic government and industry backing.
Tokamak Energy: a $52 million upgrade with the US and UK governments
Tokamak Energy, spun out of the UK Atomic Energy Authority's Culham Laboratories and based at Milton Park near Didcot, achieved 100 million degrees in its compact ST40 spherical tokamak in 2022 — the first time a privately owned company had reached that threshold.
In late 2024, the company entered a five-year, $52 million public-private partnership with the US Department of Energy and the UK's Department for Energy Security and Net Zero to upgrade ST40, coating its inner wall with lithium to improve plasma confinement, with technical collaboration from Princeton Plasma Physics Laboratory and Oak Ridge National Laboratory. The upgrade — running through 2026 under the name LEAPS — included the replacement of ST40's centre column, a component that had withstood over 5,000 plasma pulses.
Separately, Tokamak Energy holds a £70 million contract as Magnet Systems Partner for the UK Government's STEP fusion programme, running to 2029, and is working with Japan's Furukawa Electric Group on UK-based manufacturing of high-temperature superconducting tape.
Nexeon: silicon anode technology for the battery supply chain
Nexeon, based at Milton Park, develops silicon-based anode materials for lithium-ion batteries, supplying Tier 1 global battery manufacturers and OEMs.
In August 2022 the company completed the second close of a fundraise resulting in $170 million of total investment, plus a further $50 million of related commercial investment from strategic partners — a combined raise the company itself described as over $200 million. Nexeon operates from Oxfordshire and Yokohama, Japan.
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UK Inward Investment Guides: Oxfordshire
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