Boost for fusion as ST40 achieves first plasma following upgrade

Tokamak Energy’s quest to demonstrate grid-ready fusion power by the early 2030s has received a boost after its upgraded ST40 compact spherical tokamak achieved first plasma following an upgrade.

In March, 2022 the company demonstrated a world-first by reaching a plasma temperature of 100 million degrees Celsius in the ST40 tokamak, which is the threshold required for commercial fusion energy and the highest temperature achieved in a privately funded spherical tokamak.

Tokamak Energy’s ST40 returned to service after an upgrade programme that included installing a new Thomson scattering high-powered laser system to give greater insights into plasma behaviour by measuring temperature and density at several points in the plasma.

The new experiments, which Tokamak Energy said can reach plasma temperatures over six times hotter than the core of the sun, relate to future features that will be incorporated in the company’s recently announced ST80-HTS, the world’s first high field spherical tokamak using high temperature superconducting (HTS) magnets, and the fusion pilot plant, ST-E1.

In a statement, Chris Kelsall, Tokamak Energy CEO, said: “We’re in a race against time to phase out fossil fuels and make fusion energy a globally available solution for the world’s energy needs.

“Our upgraded ST40 with its new high-powered laser measurement system will help us move forward on our mission to achieve clean, secure, low cost and globally deployable commercial fusion energy. These tests will also develop critical know-how on operating future fusion power plants.”

Tokamak Energy, a commercial fusion energy company based near Oxford, is pursuing the global deployment of commercial fusion through the combined development of spherical tokamaks with high temperature superconducting (HTS) magnets.

A fusion milestone was reached in the US on December 5, 2022, with the achievement of fusion ignition at the US Department of Energy’s Lawrence Livermore National Laboratory (LLNL). LLNL’s experiment surpassed the fusion threshold by delivering 2.05MJ of energy to the target, resulting in 3.15MJ of fusion energy output.