Brit boffins boast of beating barriers to building fusion power
By Dan Robinson
UK researchers at the UK Atomic Energy Authority (UKAEA) report a major stride toward practical fusion power. During the fifth wave of MAST (Mega Amp Spherical Tokamak) Upgrade experiments (2025–26) at Culham, they produced over 1,100 fusion plasmas and achieved their highest stable pressure yet without destabilizing the hot core. They demonstrated effective suppression of Edge Localized Modes (ELMs) using QCE-mode and Resonant Magnetic Perturbations (RMP), along with stable operating regimes QH-mode and I-mode that boost confinement while limiting ELMs. A real-time, light-based plasma-position sensing method from the divertors points toward automated control for future reactors. The team also explored negative triangularity shapes and plans further upgrades—two new neutral beam injectors and an Electron Bernstein Wave system—ahead of a sixth experimental series in 2028. These advances, plus UK targets to reach commercial fusion by the end of the decade, push fusion closer to reality.