High Temperature Superconducting (HTS) tapes are innovative high field magnet conductors that make compact fusion possible.
Superconductivity is an ability held by a select group of materials capable of carrying electrical currents with zero electrical resistance. These make for ideal electro-magnet conductors, since they can carry the magnet current without overheating.
For most practical superconductors, this amazing property only works at very low temperatures, around -269°C, with limited magnetic fields. The latest generation ‘high temperature’ superconducting (HTS) tapes exceed these limitations, operating at elevated temperatures with extremely high magnetic fields.
The fusion magnets still need to be cooled to around -250°C, but this is over five times more energy-efficient than the low temperature predecessors.
HTS tapes are multi-layered conductors made mostly of strong and conductive metals, but with a crucial internal coating of ‘rare earth barium copper oxide’ (REBCO) superconducting material. The tapes are typically 12mm wide and less than 0.1 mm thick, containing just a ‘human hair’ of REBCO deposited as a thin coating.
Manufactured commercially by worldwide suppliers in lengths up to 1 km, these incredible conductors can carry 1000s of amperes of electrical current under fusion operational conditions.
When wound into coils, HTS tapes can generate much higher magnetic fields than conventional superconducting magnets, while taking up far less space and requiring far less cooling power.