In a significant advancement for fusion energy research, scientists at the Max-Planck-Institute for Plasma Physics have successfully achieved a quasi-continuous exhaust (QCE) regime in the Joint European Torus (JET) with a metal wall. This groundbreaking development, reported by lead author M. Faitsch, marks a pivotal moment in the quest for efficient and sustainable fusion power, particularly in the context of deuterium-tritium (D-T) operations.
The QCE regime is noteworthy for its ability to operate without the large-scale edge localized modes (ELMs) that can disrupt plasma stability. Instead, it features a unique mechanism that allows for high-density plasma at the edge while maintaining energy confinement akin to the high-performance H-mode operation. “The QCE regime combines the best of both worlds—high density and effective energy confinement—making it a promising avenue for future fusion reactors,” Faitsch explained.
This achievement builds on insights gained from medium-sized tokamaks like ASDEX Upgrade and TCV, where extensive experimental and modeling efforts laid the groundwork. The process to reach the QCE regime in JET involved two critical steps: enhancing plasma shaping through increased elongation and triangularity, and ensuring sufficient fuelling to elevate density at the plasma pedestal. The introduction of neon seeding has further proven advantageous, helping to suppress type-I ELMs while optimizing the fuelling of main ions.
The implications of this research extend beyond scientific curiosity; they represent a potential leap forward for the commercial viability of fusion energy. As the energy sector grapples with the urgent need for sustainable power sources, advancements like the QCE regime could pave the way for more stable and efficient fusion reactors, ultimately contributing to a cleaner energy future. Faitsch noted, “Our findings indicate that fusion energy could soon transition from theoretical promise to practical reality, with a clear path toward commercialization.”
Published in ‘Nuclear Fusion,’ this research not only highlights the technical achievements within the JET framework but also underscores the collaborative spirit of the global fusion community. As researchers continue to refine these techniques, the dream of harnessing the power of the stars for our energy needs inches closer to reality, with the QCE regime standing as a testament to human ingenuity and perseverance in the face of energy challenges.
