MIT Achieves Sustained Net-Positive Fusion Energy for First Time
MIT's fusion experiment has achieved sustained net-positive energy output for the first time in history. The breakthrough demonstrates that fusion power plants are scientifically feasible, accelerating the path to commercial deployment.
By Emily Watson - Education & Social Issues Correspondent
Last Updated: December 17, 2025
MIT fusion breakthrough
Historic Achievement
MIT's SPARC tokamak achieved Q>2, meaning the fusion reaction produced twice as much energy as was used to heat the plasma. The reaction was sustained for 30 seconds.
Technical Breakthrough
High-temperature superconducting magnets enabled a compact design with magnetic fields four times stronger than previous experiments. The innovation dramatically reduced cost and complexity.
Path Forward
Commonwealth Fusion Systems, MIT's spin-off, is building a demonstration power plant targeting 2030 operation. Fusion could provide unlimited clean energy within a generation.