Tokamak Energy achieves crucial plasma temperature

10 March 2022

Tokamak Energy of the UK announced it has demonstrated a world-first with its privately-funded ST40 spherical tokamak, achieving a plasma temperature of 100 million degrees Celsius, the threshold required for commercial fusion energy.

The ST40 spherical tokamak (Image: Tokamak Energy)

Oxford, England-based Tokamak Energy said this is "by far the highest temperature ever achieved in a spherical tokamak and by any privately funded tokamak". It noted that while several government laboratories have reported plasma temperatures above 100 million degrees Celsius in conventional tokamaks, this milestone has been achieved in just five years, for a cost of less than GBP50 million (USD66 million), in a much more compact fusion device.

The company added that the milestone of achieving 100 million degrees Celsius plasma has been verified by an independent advisory board consisting of international experts.

"This achievement further substantiates spherical tokamaks as the optimal route to the delivery of clean, secure, low-cost, scalable and globally deployable commercial fusion energy," Tokamak Energy said.

The ST40 device will now undergo an upgrade and be used to develop technologies for future devices. The ST-HTS, which will be the world's first spherical tokamak to demonstrate the full potential of high-temperature superconducting (HTS) magnets, is due to be commissioned in the mid-2020s. This device will demonstrate multiple advanced technologies required for fusion energy and inform the design of a world first fusion pilot plant, to be commissioned in the early 2030s.

Tokamak fusion reactors use magnets to contain and isolate a plasma so that it can reach the high temperatures at which fusion occurs. High magnetic fields are necessary for tokamaks to contain the superheated fuel, and higher magnetic fields enable a smaller tokamak. High-temperature superconductors can create these much stronger magnetic fields and so are important for commercial fusion power.

Tokamak Energy - which grew out of the Culham Centre for Fusion Energy, also based in Oxfordshire - is also manufacturing a complete HTS magnet system, which will be the first validation of strong magnetic fields with HTS coils in a spherical tokamak.

"We are proud to have achieved this breakthrough which puts us one step closer to providing the world with a new, secure and carbon-free energy source," said Tokamak Energy CEO Chris Kelsall.

"When combined with HTS magnets, spherical tokamaks represent the optimal route to achieving clean and low-cost commercial fusion energy. Our next device will combine these two world leading technologies for the first time and is central to our mission to deliver low-cost energy with compact fusion modules."

Researched and written by World Nuclear News