France has taken a major leap forward in the race for nuclear fusion energy, achieving a new world record for plasma duration. On February 12, 2025, scientists at the French Alternative Energies and Atomic Energy Commission (CEA) successfully sustained a plasma reaction for 1,337 seconds—over 22 minutes—inside the WEST tokamak reactor.
This breakthrough surpasses the previous record of 1,066 seconds, set by China’s EAST tokamak in January 2025, marking a 25% improvement. More importantly, it demonstrates the growing ability to control fusion reactions for extended periods, a crucial step toward making fusion energy a practical power source.
What Makes This Record-Breaking Plasma Special?
Located at the CEA Cadarache site in southern France, WEST (W Environment in Steady-state Tokamak) is a cutting-edge research facility designed to explore the conditions necessary for sustainable fusion power.
During this experiment, the plasma inside WEST reached temperatures of 50 million degrees Celsius—hot enough to sustain nuclear fusion. The team also confirmed that the reactor’s plasma-facing components remained stable, proving that materials can withstand prolonged exposure to extreme heat and radiation.
According to Anne-Isabelle Etienvre, Director of Fundamental Research at the CEA, this milestone is a major technological step forward.
“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. Experiments will continue with increased power. This excellent result allows both WEST and the French community to lead the way for the future use of ITER.”, comment Anne-Isabelle Etienvre, Director of Fundamental Research at the CEA.
Why Nuclear Fusion Is the Future of Clean Energy
Nuclear fusion is often described as the “holy grail” of clean energy. Unlike nuclear fission, which powers today’s reactors by splitting atoms, fusion generates energy by fusing hydrogen isotopes, producing helium and enormous amounts of heat.
The potential benefits of fusion are immense. Fusion power offers virtually limitless energy, as its fuel, derived from hydrogen, is abundant and widely available. Unlike fossil fuels, fusion does not produce greenhouse gas emissions, making it an environmentally friendly solution for large-scale energy production. Furthermore, unlike traditional nuclear fission, fusion creates minimal radioactive waste, as it does not generate long-lived radioactive byproducts.
However, the main challenge has always been maintaining plasma long enough for energy generation to be viable. Plasma, the superheated gas where fusion reactions occur, must be confined within a strong magnetic field inside a tokamak reactor. If the plasma becomes unstable, the reaction stops.
The recent achievement at WEST brings scientists closer to solving this challenge, offering new hope that fusion can become a practical energy source in the near future.
How Does West Compare to Other Fusion Projects?
WEST is part of an international effort to develop nuclear fusion, alongside major projects like ITER, EAST, JT-60SA, and KSTAR. ITER, located in France, is the world’s largest fusion experiment and is set to begin operations in the 2030s. EAST, China’s Experimental Advanced Superconducting Tokamak, previously held the record for plasma duration, but WEST’s latest breakthrough has now surpassed it.
In Japan, JT-60SA is testing new reactor designs that could eventually be used in commercial fusion power plants. South Korea’s KSTAR project is also making strides in sustaining high-temperature plasmas for extended periods.
These projects are working together to develop the technologies needed for commercial fusion reactors, with WEST’s latest findings providing valuable data for ITER’s future operations. By proving that long-duration plasma reactions are achievable, WEST is helping to refine the engineering and materials that will be required for full-scale fusion power plants in the future.
What’s next for fusion energy?
While WEST itself will never become a commercial power plant, its success lays the foundation for future reactors that could power entire cities with fusion energy. The next phase of research will focus on extending plasma durations even further, eventually aiming for multi-hour sustained reactions.
Increasing the heating power to achieve even higher temperatures, closer to 100 million degrees Celsius, will also be a priority. Additionally, scientists will continue testing new materials to ensure reactor components can withstand prolonged fusion conditions without degrading.
Despite these advances, fusion power is still years away from large-scale deployment. Scientists must overcome key challenges, including achieving net energy gain, meaning the reactor must produce more energy than it consumes. Currently, no fusion reactor has successfully reached this milestone, but WEST’s latest experiment brings that goal one step closer.
