Tokamak Energy on October 26 announced plans to construct a high field spherical tokamak using high-temperature superconducting (HTS) magnets. Dubbed the ST80-HTS, the machine would demonstrate multiple technologies required to achieve commercial fusion energy, the company says. Tokamak Energy plans to complete the ST80-HTS in 2026 to demonstrate spherical tokamak operations and inform the design of its successor, a fusion pilot plant called ST-E1 that the company says could deliver electricity into the grid in the early 2030s and produce up to 200 MWe.
Temperature milestone: Earlier this year, the company’s ST40 spherical tokamak reached the commercial fusion energy plasma temperature threshold of 100 million °C with what was reported as the highest triple product (an industry measure of plasma density, temperature, and confinement) of any private fusion energy company. The ST40 achieved those results with a plasma volume of less than one cubic meter, which is 15 times less volume than any other tokamak that has achieved the same threshold.
“High performance in smaller spherical tokamaks is the key to commercial fusion power,” said Chris Kelsall, chief executive officer of Tokamak Energy said. “We are proud to have achieved this result in collaboration with the Princeton and Oak Ridge National Laboratories.”
New goals: The ST80-HTS could set a new record for sustained triple product, the company says, and achieve long pulse (about 15 minutes) control of the plasma. Triple product results typically diminish as pulse duration increases, but the ST80-HTS would target significantly longer pulse durations that are needed for sustained high power output in commercially competitive fusion power plants.
“Our next high field spherical tokamak, the ST80-HTS, has the goal of demonstrating the engineering solutions needed to make commercial fusion energy a reality, providing the foundation for the global deployment of fusion power plants in the mid-2030s,” said Kelsall.
U.K. base for international collaboration: Tokamak Energy was founded in 2009 as a spin-off from the U.K. Atomic Energy Authority’s (UKAEA) Culham Centre for Fusion Energy (CCFE), and it currently employs a team of over 220 people based near Oxford, U.K., less than five miles from the CCFE. On October 10, Tokamak Energy and the UKAEA announced that they had signed a framework agreement to collaborate on developing spherical tokamaks for power production.
Tokamak Energy has received six INFUSE grants from the U.S. Department of Energy and has worked with ORNL and PPPL. Earlier this year, Tokamak Energy and the University of Illinois–Urbana-Champaign received a $500,000 INFUSE grant to study lithium plasma-facing technologies.