Uploaded April 2025 | Updated September 2026, 2 weeks ago
High temperature superconducting (HTS) magnets are a game changer for fusion. As we gear up for operations with our flagship Demo4 fusion magnet system, Chief Engineer, Graham Dunbar provides a progress update and explains the importance of building and testing in a full tokamak configuration. The knowledge we're gaining puts us at the forefront of designing and building large scale HTS magnet systems, which are essential for achieving commercial fusion energy.
Demo4 is a world-first complete set of high-field HTS magnets in a tokamak configuration. It comprises 44 individual coils assembled into 14 toroidal field (TF) limbs and two poloidal field (PF) coils. Operating in a vacuum at 20 Kelvin (-250°C), it will generate a magnetic field nearly a million times stronger than the Earth’s.
High temperature superconducting (HTS) magnets are a game changer for fusion. As we gear up for operations with our flagship Demo4 fusion magnet system, Chief Engineer, Graham Dunbar provides a progress update and explains the importance of building and testing in a full tokamak configuration. The knowledge we're gaining puts us at the forefront of designing and building large scale HTS magnet systems, which are essential for achieving commercial fusion energy.
Demo4 is a world-first complete set of high-field HTS magnets in a tokamak configuration. It comprises 44 individual coils assembled into 14 toroidal field (TF) limbs and two poloidal field (PF) coils. Operating in a vacuum at 20 Kelvin (-250°C), it will generate a magnetic field nearly a million times stronger than the Earth’s.
