A prototype high field spherical tokamak constructed with high-temperature superconducting (HTS) magnets is in the planning stages by U.K.-based Tokamak Energy. The ST80-HTS is expected to demonstrate multiple technologies required to achieve commercial fusion energy when completed in 2026.

The ST80-HTS will be engineered to inform the design of its successor, the ST-E1 fusion pilot plant that could deliver electricity into the grid in the early 2030s and produce up to 200 MWe. The company’s ST40 spherical tokamak recently 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.

ST80-HTS will be the world’s first high field spherical tokamak to demonstrate the full potential of high temperature superconducting magnets. Source: Tokamak Energy

The ST80-HTS could set a new record for the triple product metric by achieving long-pulse, 15-minute control of the plasma and approach the pulse durations essential for sustained high power output in commercially competitive fusion power plants.