Researchers at the Joint European Torus (JET) facility have achieved a new world record for fusion energy output, generating 59 megajoules from a sustained reaction. Announced by the EUROfusion consortium, the result was produced during the facility's recent DTE2 experimental campaign using a deuterium-tritium (D-T) fuel mix. This output surpasses the previous 21.7 MJ record, also set at JET in 1997, by more than a factor of two. The experiment demonstrates the ability to generate and sustain fusion reactions in a tokamak configuration over commercially relevant timescales, providing critical operational data for future power plants and the next-generation ITER device. Source: EUROfusion

The record-setting pulse sustained an average fusion power of approximately 11 MW over a five-second period. This achievement is not a measure of net energy gain, or Q_plasma, but rather a demonstration of sustained, high-power plasma stability in a machine with actively cooled, non-superconducting copper magnets. The experiments were designed specifically to test integrated scenarios and control schemes under conditions that approximate those expected in ITER. Validating the physics models at this scale is a primary objective for the JET program, as it reduces operational risks and informs the commissioning strategy for the larger, more powerful international experiment currently under construction. Source: EUROfusion

The record-setting pulse sustained an average fusion power of approximately 11 MW over a five-second period.

Operating with a D-T fuel mixture presents significant materials science and engineering challenges, particularly regarding neutron activation of machine components and the handling of tritium. The JET team's ability to successfully manage these factors during the DTE2 campaign provides invaluable experience. The machine's carbon wall was previously replaced with an ITER-like beryllium and tungsten wall to study plasma-wall interactions with materials that will be used in future reactors. The data gathered on material performance, fuel retention, and dust production under high neutron flux are essential for finalizing ITER's operational plans and for the design of DEMO-class fusion power plants. This work represents a key part of the public-sector fusion effort. Source: EUROfusion

This result from JET concludes a series of experiments intended to be the facility's final D-T campaign before its scheduled decommissioning. For over four decades, JET has been a central hub for European fusion research and a critical testbed for plasma physics, heating systems, and control technologies. Its contributions have been foundational to the design and scientific mission of ITER. The successful completion of this final experimental phase provides a capstone achievement, transferring a robust dataset and operational legacy to the next generation of fusion devices. The performance validates key scientific assumptions and boosts confidence in the projected performance of ITER, which aims to produce 500 MW of fusion power from 50 MW of input heating power. Source: EUROfusion