The world’s only net-positive fusion experiment has been steadily ramping up the amount of power it produces, TechCrunch has learned.

In recent attempts, the team at the U.S. Department of Energy’s National Ignition Facility (NIF) increased the yield of the experiment, first to 5.2 megajoules and then to 8.6 megajoules, according to a source with knowledge of the experiment.

The new results are significant improvements over the historic experiment in 2022, which was the first controlled fusion reaction to generate more energy than it consumed.