PrivateFounded 2009🇬🇧Milton Park, Oxfordshire, United KingdomCEO Warrick Matthews
Tokamak Energy is a UK fusion and high-temperature superconducting (HTS) company spun out of the UK Atomic Energy Authority in 2009.
Latest update Oct 7, 2026
01
It now describes itself first as a commercial superconducting and fusion-technologies supplier rather than the builder of its own power plant: the August 2026 Nuclear Fusion Focus Collection published the ST-E1 pilot-plant design, and the company said it will not go on to construct that plant or future pilot plants itself. Its operating machine is ST40, which reached 100 million degrees Celsius in 2022 and closed out 2025 with three records (1 MA plasma current, highest stored energy, triple product up over 30% to about 8 x 10^18 m^-3 keV s) before entering a $52M DOE/DESNZ upgrade that still runs through most of 2026. On September 9, 2026 Tokamak Energy completed a 14-month Demo4 campaign, pushing the 44-coil HTS magnet system to a peak field of 13.7 tesla (up from the November 2025 11.8 T system-level result), 5,600 amps in the toroidal-field coils, 150 MPa transverse stress, and roughly 10,000 operating hours, with results presented at the Applied Superconductivity Conference in Pittsburgh. In April 2026 Tokamak Energy was named Magnet Systems Partner for the UK government's STEP prototype under a £70M contract to March 2029. TE Magnetics sells that capability commercially (Ridgway Machines acquired in 2025; a 2025 General Atomics/DARPA undersea-propulsion magnet contract; an April 2026 data-center HTS power-distribution study), and the company also supports the FAST superconducting-tokamak project in Japan.
tokamakenergy.comUpdated Sep 17, 2026
02
2026-2029
Execute the eight magnet work packages under the £70M STEP contract with UK Fusion Energy, covering magnets, tokamak systems and plasma integration, and use ST40 as the test bed for magnetic configurations feeding STEP's later design phases. After the company said it will not construct its own pilot plants, STEP is the flagship construction programme Tokamak Energy is attached to. The September 9, 2026 Demo4 campaign close is already feeding STEP model-coil testing.
2026-2028
Turn the June 2026 Furukawa Electric collaboration into domestic UK production of high-temperature superconducting tape, the single largest supply constraint on HTS magnet programmes - STEP's magnet system alone is expected to need around 30,000 km of it. US-based production at Furukawa subsidiary SuperPower Inc in New York has already delivered first tape batches; UK-based manufacturing capability is still being evaluated.
2026-2028
Move the consortium formed in May 2026 with Type One Energy and AECOM toward the first private-sector-led commercial fusion power plant project in the UK. After Tokamak Energy said it will not construct future pilot plants itself, its likeliest role is as HTS magnet and systems partner rather than plant owner-builder.
2027-2028
Finish installing the new Rockwood Group-built centre column, lithium-coated all-metal plasma-facing components, the gyrotron radiofrequency heating system that passed site acceptance testing in July 2026, and the rest of the DOE/DESNZ-funded LEAPS upgrade package, then bring ST40 back online for the next campaign studying RF start-up and ramp-up and lower-recycling regimes. Re-verified September 17, 2026: ST40 remains in the upgrade shutdown; Tokamak Energy's latest news is the Demo4 campaign close, with no ST40 restart announced.
03
Tokamak Energy said a Focus Collection of 11 peer-reviewed papers it edited was published in Nuclear Fusion, the field's most prestigious journal, spanning plasma physics, engineering systems and commercial considerations for a fusion pilot plant. The work grew out of the company's participation in the US Department of Energy's Milestone-Based Fusion Development Program and reinforces the importance of high-temperature superconducting magnet design to a commercial fusion power plant's performance and affordability.
04
Compact high-field spherical tokamak operating at the company's Oxfordshire campus since 2018 and the machine behind its plasma records. The spherical geometry confines plasma more efficiently per unit of magnetic field than a conventional tokamak, which is what makes a smaller, cheaper power plant plausible.
The company's high-temperature superconducting magnet business, built on REBCO tape wound in-house, sold both into fusion programmes and into non-fusion markets including power distribution, propulsion, motors and generators, and analytical science. Demo4, its 44-coil demonstration system, is the technology proof point.
Tokamak Energy's published fusion pilot-plant design, intended to show that a compact spherical tokamak with HTS magnets could deliver electricity to the grid. An 11-paper Focus Collection in Nuclear Fusion (August 2026) documented the pre-concept design; the company said in the same announcement that it will not construct the plant itself.
05
Near-term revenue comes from HTS magnet systems and engineering contracts through TE Magnetics, anchored by the £70M STEP magnet partnership to March 2029, the DARPA/General Atomics submarine-propulsion magnet contract, and Ridgway Machines' industrial manufacturing business. After the August 2026 decision not to construct ST-E1, magnet and systems supply to partner programmes is the commercial path rather than selling power from a company-owned plant. The September 9, 2026 Demo4 campaign close is the latest magnet-system proof point behind that commercial path.
(Sept 2026 campaign close; 5,600 A TF coils, 150 MPa, ~10,000 hours). November 2025 first system-level result was 11.8 T / 7 million ampere-turns
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Operating status
Pre-revenue (electricity); magnet business generating revenue
ST40 is in a major shutdown running through most of 2026 under the DOE/DESNZ-funded LEAPS programme, with a new Rockwood Group-built high-field centre column, lithium-coated plasma-facing components, all-metal walls, an upgraded Thomson scattering diagnostic and radiofrequency heating being installed; the gyrotron heating system passed site acceptance testing in July 2026 and the next experimental campaign remains scheduled for 2027-2028. On September 9, 2026 Tokamak Energy completed a 14-month Demo4 campaign at 13.7 tesla, 5,600 amps, 150 MPa and roughly 10,000 operating hours, validating a full HTS magnet system and feeding STEP model-coil work. TE Magnetics is delivering magnet work commercially as STEP's Magnet Systems Partner under a £70M contract to March 2029. After publishing the ST-E1 design in an August 2026 Nuclear Fusion Focus Collection, Tokamak Energy said it will not construct that plant or future pilot plants itself, and now frames its role as enabling government and industry programmes (STEP, FAST in Japan, DOE milestone design work) plus commercial HTS systems.
STEP magnet systems partnership
£70M contract to March 2029 as Magnet Systems Partner for the UK government's STEP prototype fusion power plant, covering eight work packages delivered with UK Fusion Energy across magnets, tokamak systems and plasma integration. STEP's magnet system is expected to require roughly 30,000 km of HTS tape.
Commercial HTS magnet division launched in 2024, selling magnet systems beyond fusion into power distribution, propulsion, motors and generators, analytical science, life sciences and, per 2026 statements, data-center infrastructure. Manufacturing capacity was expanded by the 2025 acquisition of Ridgway Machines, and in October 2025 the division was contracted by General Atomics to supply HTS magnets for DARPA's undersea magnetohydrodynamic propulsion programme, its first disclosed defense-sector contract. The division has stated an ambition to become an end-to-end, design-to-manufacturing HTS technology provider.
Government research programmes
Milestone-based and co-funded public programmes, including the $52M ST40 upgrade split equally between the U.S. Department of Energy, the UK's DESNZ and Tokamak Energy, plus UKAEA programme awards such as the LIBRTI tritium-breeding bid won in 2025.
07
How past announced dates turned out.
0/2announced dates hit on time
Build ST80-HTS at Culham
Target Late 2020s · Resolved Sep 6, 2026
The original 2022-23 plan called for ST80-HTS build completion in 2026 at UKAEA Culham as the step before ST-E1. No completion has been announced, and the company's September 2026 about-page roadmap no longer lists ST80-HTS. Combined with the August 2026 statement that Tokamak Energy will not construct future pilot plants, the prototype is treated as superseded rather than still expected on the old path.
Deliver grid electricity from ST-E1
Target Early 2030s · Resolved Aug 18, 2026
Tokamak Energy published the ST-E1 pre-concept design in an 11-paper Nuclear Fusion Focus Collection on August 18, 2026, and said in the same announcement that it will not construct that plant. Managing Director of Fusion Ross Morgan separately said the company will not construct future pilot plants itself. The milestone is no longer expected as a Tokamak Energy-built plant.
08
2026
Demo4 14-month campaign closes at 13.7 tesla
On September 9, 2026 Tokamak Energy announced it had completed a 14-month campaign on Demo4, its 44-coil HTS magnet system in a spherical-tokamak configuration. Engineers pushed a peak field of 13.7 tesla, ran toroidal-field coils at 5,600 amps, cycled the system from 77 K to 17 K, withstood 150 MPa transverse stress, and accumulated roughly 10,000 hours of energisation, including forced discharges at up to 12.5 T. Results were presented at the Applied Superconductivity Conference in Pittsburgh and are feeding STEP model-coil work under the £70M magnet partnership.
Focus Collection published; company will not construct ST-E1
On August 18, 2026 Tokamak Energy publishes an 11-paper Focus Collection in Nuclear Fusion covering plasma physics, engineering systems and the ST-E1 fusion pilot-plant design, grown out of the US Department of Energy's Milestone-Based Fusion Development Program. In the same announcement the company says it will not go on to construct that plant, positioning the papers as a design and systems-integration contribution while its commercial path runs through HTS magnets, ST40 and partner programmes such as STEP.
Gyrotron heating system passes site acceptance testing
On July 29, 2026 the high-power gyrotron fuel-heating system passes site acceptance testing ahead of installation on the upgraded ST40, one of the last major pieces of the DOE/DESNZ upgrade programme before experiments restart.
SOPHIA simulation software deployed at Lancaster University's nuclear simulator
Lancaster University opens the Lancaster University Nuclear Operations Simulator, a 2 million pound, Office for Students-funded facility that recreates Tokamak Energy's ST40 control room and runs the company's SOPHIA fusion simulation software alongside pressurized-water-reactor and small-modular-reactor code from GSE Solutions, Westinghouse and Norway's Institute for Energy Technology. It is described as the UK's first reconfigurable nuclear operations training simulator spanning fission and fusion, and opens for teaching from the 2026-2027 academic year.
Furukawa Electric partnership on UK HTS tape capability
In June 2026 Tokamak Energy and Japan's Furukawa Electric Group advance their collaboration toward building high-temperature superconducting tape manufacturing capability in the UK, addressing the supply bottleneck behind every HTS fusion magnet program.
UK Infinity Fusion Consortium formed
On May 6, 2026 Tokamak Energy, stellarator developer Type One Energy and engineering firm AECOM form the UK Infinity Fusion Consortium to pursue the first private-sector-led commercial fusion power plant project in Britain.
Study finds HTS could transform data-center power distribution
On April 29, 2026 Tokamak Energy publishes a study showing HTS busway could cut power losses in data-center power distribution by up to 90%, lifting system efficiency from around 90% to about 99% in a modeled 10 MW data center and freeing up to 9% more IT capacity from the same electrical supply - a new non-fusion application for the TE Magnetics HTS platform.
Named Magnet Systems Partner for STEP
On April 14, 2026 Tokamak Energy is confirmed as Magnet Systems Partner for STEP, the UK government's prototype fusion power plant at West Burton, under a £70M contract running to March 2029 covering eight work packages with UK Fusion Energy. The deal also gives STEP access to ST40 for testing magnetic configurations and plasma scenarios, and makes Tokamak Energy the UK's only specialist manufacturer of high-field HTS magnet technology.
2025
Three ST40 records before the upgrade shutdown
The December 2025 campaign ends with ST40's highest plasma current (1 mega-amp, up from 0.85 MA), close to double its previous stored energy, and a fusion triple product up more than 30% to roughly 8 (±2) x 10^18 m^-3 keV s. ST40 then enters the DOE/DESNZ-funded upgrade shutdown that runs through most of 2026.
Demo4 reproduces fusion power plant magnetic fields
In November 2025 Demo4, a full HTS magnet system of 44 coils, reaches 11.8 tesla with seven million ampere turns at cryogenic temperatures - the first time an HTS magnet system has reproduced fusion-relevant magnetic environments at system level rather than in a single coil.
Strategic partnership with Saudi Arabia's KACST
On November 4, 2025 Tokamak Energy and Saudi Arabia's King Abdulaziz City for Science and Technology sign an international strategic partnership at Riyadh's Future Investment Initiative, covering joint fusion and HTS training and education, collaborative R&D and conceptual design work, and HTS applications for power distribution.
Contracted by General Atomics on DARPA submarine propulsion programme
On October 21, 2025 Tokamak Energy is contracted by General Atomics to provide simulation, design and fabrication of HTS magnets for DARPA's Principles of Undersea Magnetohydrodynamic Pumps (PUMP) programme, which aims to propel submarines silently with no rotating parts. General Atomics handles system integration and prime contractor HRL Laboratories develops the electrode technology; delivered through TE Magnetics, it is the division's first publicly disclosed defense-sector contract.
Tokamak Energy Inc. selected for U.S. DOE FIRE Collaboratives award
On October 9, 2025 Tokamak Energy's U.S. subsidiary, Tokamak Energy Inc., is selected for the Department of Energy's $128M Fusion Innovative Research Engine (FIRE) Collaboratives initiative, advising on eight projects with U.S. national labs and universities and helping develop advanced HTS tape designed to withstand neutron irradiation as part of a University of Houston-led project.
Strategic HTS collaboration signed with Gauss Fusion
On October 7, 2025 Tokamak Energy and Gauss Fusion, a stellarator-focused fusion industrialization company, sign a strategic collaboration covering HTS magnet design development, integration and testing support, and the path to commercial scale - part of a wider pan-European industrial push to strengthen the continent's supply chain for fusion magnet technology.
Tokamak Energy acquires Ridgway Machines, a UK manufacturer of coil-winding and electrical-equipment machinery, to bring superconducting magnet manufacturing capacity in-house and accelerate the growth of its TE Magnetics business.
2024
$52M transatlantic ST40 upgrade agreed
The U.S. Department of Energy, the UK's Department for Energy Security and Net Zero and Tokamak Energy agree to fund a $52M, five-year upgrade of the privately owned ST40 in equal thirds, adding lithium wall conditioning, all-metal plasma-facing components and radiofrequency heating to study conditions relevant to future power plants.
TE Magnetics launched and $125M raised
Tokamak Energy carves out TE Magnetics in September 2024 to sell HTS magnet systems into fusion, power distribution, propulsion, medical and analytical-science markets, then raises $125M in November led by East X Ventures and Lingotto Investment Management to commercialize both the fusion and magnet businesses.
2022
2018
2015
2009
09
$460Mdisclosed across 3 rounds with a stated amount
Cumulative disclosed raise · dated rounds
Private investment to date
2009-2024
LRG Capital Group, Hans-Peter Wild, David Harding, East X Ventures, Lingotto Investment Management and others
Government funding
2009-2024
UK government, U.S. Department of Energy
Series C
2024-11
East X Ventures, Lingotto Investment Management, existing investors
