Once a government-led pursuit, nuclear fusion is now a private-capital race, much of it financed by the same people building AI.

In late 2022, Lawrence Livermore National Laboratory achieved a historic nuclear fusion breakthrough by creating a fusion reaction that produced more energy than the lasers used to create it.

For most of the past 70 years, fusion energy has been shorthand for a promise that never quite arrived, a running joke about a technology that was always a few decades away. That timeline has shifted.

The massive energy demands of the artificial intelligence boom are accelerating the private-sector development of nuclear fusion, which promises a clean and limitless power source.

While not as highlight-reel worthy as the Winter Olympics and the World Cup, experts expect high-performance computing (HPC) to have an even bigger ...