Researchers in the U.K. have taken a step closer to achieving the strong magnetic fields needed to confine and control extremely hot, positively charged hydrogen fuel and create sustainable fusion energy. Tokmak Energy engineers have assembled a world-first set of high-temperature superconducting (HTS) magnets for deployment in fusion power systems.

According to Tokamak Energy, its new Demo4 facility will consist of 44 individual magnetic coils recently manufactured using 38 km of HTS tape, which carries currents with zero electrical resistance and requires five times less cooling power than traditional superconducting materials. The system will have a magnetic field strength of more than 18 Tesla, nearly 1 million times stronger than the Earth’s magnetic field.

The magnets are wound with precision from the HTS tapes, typically 12 mm wide and less than 0.1 mm thick, which are multilayered conductors made mostly of strong and conductive metals with an internal coating of rare Earth barium copper oxide superconducting material.

The HTS tape is used in the new HTS magnets. Source: Tokamak Energy

The facility will incorporate 14 toroidal field limbs and a pair of poloidal field coil stacks to form a cage-shaped structure. Tests will be conducted at an extremely low temperature of -253° C and are expected to inform designs and operational scenarios for the company’s advanced prototype, ST80-HTS, and the subsequent fusion power plant, ST-E1.