Breakthrough came after experiment with 192 high-energy lasers, say US energy officials

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The energy department’s press conference on the breakthrough in its fusion experiment has wrapped up, but before it concluded, a top official said it could be a long time before the technology becomes commonly used.

“There are very significant hurdles, not just in the science but in technology,” said Kim Budil, director of the Lawrence Livermore National Laboratory, where the experiment was conducted. “This is one igniting capsule one time, and to realize commercial fusion energy, you have to do many things. You have to be able to produce many, many fusion ignition events per minute, and you have to have a robust system of drivers to enable that.”

Inside that was a small, spherical capsule about half the diameter of a BB. One hundred and ninety two laser beams entered from the two ends of the cylinder and struck the inner wall. They didn’t strike the capsule, they struck the inner wall of this cylinder and deposited energy, and that happened in less time than it takes light to move 10 feet, so it’s kind of fast.

X-rays from the wall impinged on the spherical capsule. Fusion fuel in the capsule got squeezed. Fusion reaction started.