Super-X exhaust with long 'legs' could reduce nuclear reactor heat

An international research team at the UK’s MAST Upgrade facility has successfully demonstrated the Super-X divertor, an innovative exhaust system for fusion reactors that can reduce heat loads on reactor walls by more than tenfold compared to previous designs. The Super-X divertor features longer “legs” that provide the superheated plasma—reaching temperatures over 10,000°C—more space and time to cool before contacting any solid surface. This design significantly lowers the thermal and particle stress on the reactor’s divertor, a critical component responsible for handling the extreme conditions at the plasma edge, thereby addressing a major engineering challenge for commercial fusion power plants. The breakthrough proves that plasma conditions in the divertor can be independently controlled without affecting the core plasma where fusion energy is produced, a key factor for stable and continuous reactor operation. Additionally, the Super-X design is easier to manage than conventional short-legged divertors and offers flexibility for future reactor designs by balancing performance with engineering complexity. These findings mark a world-first in divert