In a nuclear fusion research, France’s WEST tokamak has sustained a hot plasma for 1,337 seconds, just over 22 minutes. The result, announced by Anne-Isabelle Etienvre, Director of Fundamental Research at France’s Commissariat à l’énergie atomique et aux énergies alternatives (CEA), sets a new milestone in fusion research. It surpasses China’s EAST tokamak record by about 25%, showing that researchers can sustain demanding conditions without damaging the reactor’s inner surfaces.
Etienvre emphasized the importance of the breakthrough: “WEST has achieved a new key technological milestone by maintaining hydrogen plasma for more than twenty minutes through the injection of 2 MW of heating power.”
Inside the device, strong magnetic fields confined a swirling plasma of charged particles. The plasma remained stable while heat and particle exhaust were carefully managed so that components directly facing the plasma did not fail.
A tokamak is essentially a ring-shaped “magnetic bottle.” Its magnetic fields guide plasma particles in looping paths around a torus, keeping them away from the walls. This technique, called magnetic confinement, enables scientists to heat gases until atomic nuclei fuse, releasing energy.
France is also hosting ITER, a much larger fusion device currently under construction. ITER aims to produce about 500 megawatts of fusion power from roughly 50 megawatts of input heating—ten times more output than input.
Fusion progress is measured in multiple ways. The UK’s JET facility, for example, holds the record for energy released, producing 69 megajoules in a five-second burst. WEST’s achievement highlights endurance instead: sustaining plasma for extended periods while maintaining stability. Together, these different experiments map out the requirements for a real-world fusion power plant.
A commercial fusion reactor must run for long durations without degrading its components. That means controlling exhaust, maintaining steady plasma temperatures, and ensuring materials can withstand extreme conditions. WEST uses tungsten in its divertor region, a material known for heat resistance, but one that still requires precision to prevent damage or contamination.
It’s important to note that WEST’s 22-minute plasma did not generate net electricity. The goal was to demonstrate stable confinement, not energy surplus. Achieving net energy depends on many variables: plasma density, temperature, confinement quality, and fuel control.
CEA’s team plans longer campaigns, aiming to accumulate hours of plasma time while gradually raising power levels. These lessons will feed directly into ITER operations, bridging the gap from research experiments to plant-scale applications.