Tokamak Energy is an Oxfordshire fusion and superconducting-technology company founded in 2009. It operates the ST40 spherical tokamak, develops HTS systems through TE Magnetics, and became the STEP programme’s magnet systems partner in 2026.
Reviewed 17 October 2026. Design targets, experimental reports and issuer statements are distinguished below.
History and technology
Tokamak Energy was established in 2009 by David Kingham, Mikhail Gryaznevich and Alan Sykes. UKI2S provided a £25,000 initial investment in 2010.[1] The company combines spherical-tokamak research with HTS development.[2][3] ST40 is a plasma experiment; Demo4 is a magnet-system test platform.[4][5]
Experimental results
A 2023 Nuclear Fusion paper reported ST40 ion temperatures above 100 million K and a corresponding triple product of approximately (6±2)×10¹⁸ m⁻³ keV s.[4] These results do not demonstrate net electricity. A five-year $52 million ST40 upgrade announced in December 2024 is equally funded by DOE, DESNZ and the company, with lithium-wall and pellet-fuelling research.[6]
Magnet business and partnerships
The September 2026 Demo4 announcement reported a 13.7 T peak field and roughly 10,000 hours across different energisation states, not continuous operation at peak field.[5] STEP awarded a £70 million magnet systems contract through March 2029.[7] This is a contract, not equity financing. The November 2024 total of $335 million comprised $275 million private investment and $60 million public support.[8]
Financing and funding records
These are traceable public records, not an exhaustive account of undisclosed financing. Investor lists are non-exhaustive. Early auxiliary records have weaker evidence.
| Announcement / disclosure | Type or round | Amount (original currency) | Disclosed investors | Basis and references (Chinese notes) |
|---|---|---|---|---|
| 2010 | 探索性投资 / Pathfinder investment | GBP 25,000 | UKI2S（现由Future Planet Capital管理） | 投资方披露的初始支持，并非当时所有资金总额。[1] |
| 2016年底（辅助记录） | 早期融资 / Early financing | GBP 10 million | 本次未据一手文件确认完整名单 | Beauhurst回顾记录；未与股权申报逐笔核对。[9] |
| 截至2018-03 | 投资关系披露 / Investor relationship | 未披露 / Not disclosed | Legal & General Capital | 投资方公告确认持有相关投资；并非可量化的独立新一轮。[10] |
| 2020-01 | 股权融资 / Equity funding | GBP 67 million | 投资方回顾未列完整当轮名单 | Future Planet Capital称该次后累计超过1.2亿英镑。[1] |
| 2024-11-20 | 股权融资 / Equity funding | USD 125 million | East X Ventures、Lingotto共同领投；Furukawa Electric、British Patient Capital、BW Group、Sabanci Climate Ventures等 | 公告累计私人资本2.75亿美元，另有政府支持6000万美元。[8] |
| 2024-12-05 | 合作研究项目（非股权） / Joint R&D programme | USD 52 million programme budget | DOE、DESNZ、Tokamak Energy各承担三分之一 | 五年项目预算；不能全部作为公司取得的外部补助，更不是融资轮次。[6] |
| 2026-04-14 | STEP合同（非融资） / STEP contract | GBP 70 million contract value | UK Fusion Energy | 执行期为2026-03至2029-03，不纳入股权融资累计。[7] |
Some early rounds lack independently traceable amounts and closing dates. Equity, investor relationships, jointly funded project budgets and procurement contracts are different categories. Historical GBP and USD amounts are not recomputed using present-day exchange rates.
References
- Future Planet Capital. Tokamak Energy. 动态网页（2020年融资回顾）. [投资方资料] Accessed: 2026-10-17.
- Tokamak Energy. About us. 动态网页. [机构或企业一手公告] Accessed: 2026-10-17.
- UK Parliament. CGE0004: Written evidence submitted by Tokamak Energy. 2018. [议会存档；企业提交材料] Accessed: 2026-10-17.
- S. A. M. McNamara et al., Nuclear Fusion 63, 054002. Achievement of ion temperatures in excess of 100 million degrees Kelvin in the compact high-field spherical tokamak ST40. 2023. [同行评议论文；实验结果] Accessed: 2026-10-17.
- Tokamak Energy. Tokamak Energy completes … fusion magnet campaign. 2026-09-09. [机构或企业一手公告] Accessed: 2026-10-17.
- U.S. Department of Energy. DOE Partners with UK’s DESNZ and Tokamak Energy … $52M Upgrade … ST40. 2024-12-05. [政府项目公告] Accessed: 2026-10-17.
- UK Fusion Energy / STEP. Tokamak Energy Named as Magnet Systems Partner for STEP Fusion Programme. 2026-04-14. [合同授予方公告] Accessed: 2026-10-17.
- Tokamak Energy. Tokamak Energy raises $125m to commercialise transformative fusion and magnet technologies. 2024-11-20. [机构或企业一手公告] Accessed: 2026-10-17.
- Beauhurst. Starling Bank and Tokamak Energy secure unreported deals. 2017. [融资数据库；辅助来源] Accessed: 2026-10-17.
- Legal & General. Legal & General hires John Cummins as MD of Urban Regeneration and Clean Energy. 2018-03-09. [投资方资料] Accessed: 2026-10-17.