Pacific Fusion's new machine survived 3,000 test pulses

Fusion research usually gets headlines for temperature records or for finally getting more energy out than went in. Livermore Lab and startup Pacific Fusion just hit a less exciting milestone. Their 'Sirius' machine is a smaller version of the electrical part a real fusion plant would need. It has fired more than 3,000 test shots without breaking. That's the real gap between a lab demo and a working plant.

Sirius uses one particular way of doing fusion, called pulsed power. It dumps a huge burst of electricity into a small target for a few billionths of a second. That burst crushes the fuel until it fuses together. Sirius isn't the only approach out there. Livermore's other big fusion machine, the NIF laser, first hit fusion ignition back in 2022. That one pointed many lasers at a single target instead. Pacific Fusion is betting Sirius's design will be cheaper and simpler once it's built big enough to sell electricity to the actual power grid one day. These 3,000 test runs prove something narrower for now. Sirius delivered 95% of its input electricity to the target on each shot. It also didn't tear itself apart doing that thousands of times in a row.

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Will Sirius ever actually try to make fusion? Not yet. It's only the driver, meaning the machine that supplies the electricity. It isn't pointed at any fusion fuel. The real test comes when Pacific Fusion scales Sirius up into a full-size version that IS aimed at fuel. Until then, what Sirius does prove is reliability. That has been the specific worry with pulsed-power designs for decades. Older versions could fire a few times and then damage themselves. Sirius is the first solid evidence that a newer design might not have that problem.