News  /  Occupier News

Tokamak Energy’s record-breaking machine advances commercial fusion mission

Published on 27 October 2023

Tokamak Energy has revealed its record-breaking fusion machine has broken new ground following a series of upgrades. A Milton Park occupier since 2013, the company hopes to become the first in the world to achieve industrial scale power from fusion energy.

Its ST40 machine is a high-field spherical tokamak with copper magnets, built and operated by Tokamak Energy.  After breaking the 100 million degrees record in 2022, the machine has been through a series of hardware upgrades to improve its capabilities, including new power suppliers and diagnostic systems.

Tokamak Energy’s advances during the recent campaign, which ended in September, focused on improving understanding and developing high-performance scenarios in a high field spherical tokamak.

Dr Steven McNamara, Tokamak Energy’s Head of Plasma Systems, alongside other members of the team, will present the full results at next week’s International Atomic Energy Agency (IAEA) Fusion Energy Conference at the Queen Elizabeth II Centre in London.

Dr McNamara said: “We’re delighted with these latest machine enhancements and results, and proud of how ST40 continues to expand our understanding, further validating future power plant designs on our path to delivering clean, secure and affordable fusion energy in the 2030s.”

Inside the Tokamak there is a diverted configuration, where the magnetically confined hot gas is separated from the wall and its exhaust is directed to a dedicated ‘divertor’ region. Heat and particles are extracted here, keeping the core plasma cleaner and therefore significantly improving overall performance.

In a fusion testing plant, the heat loads on the divertor are expected to be similar to a space shuttle during re-entry.

An infrared camera was installed in collaboration with Oak Ridge National Laboratory (U.S.) to measure the power load distribution, helping to boost confidence in future power plant designs.

Some of the hardware, including the infrared camera and endoscope, was funded through the UK Government’s Department for Energy Security and Net Zero Advanced Modular Reactor (AMR) Feasibility and Development Phase 2 programme.

To achieve its milestones, Tokamak Energy upgraded the ST40 plasma control system as diverted plasmas are vertically unstable and require precise control. This enabled the team to exceed its target by achieving a diverted plasma with higher currents, sustained for longer durations.

In addition, the team also established diverted H-mode plasmas across a range of scenarios. These scenarios will be used in future operations to further develop key understanding of the performance of high-field spherical tokamaks.

It will be back in operation in early 2024 following further upgrades and maintenance.

For more information on Tokamak Energy, please visit:

Keep up to date with latest news, events and opportunities

Subscribe to our newsletter