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Buried among today’s ghastly news stories was an interesting micro-nugget of potentially good news: the National Ignition Facility at Lawrence Livermore Lab in California managed to trigger a 1.35 Megajoule reaction by firing an ultraviolet laser array into a tiny target of nuclear fuel. Now Doc-Brown-style engineers/mad scientists might scoff at that number since 1.35 Megajoules is about the same amount of kinetic energy as in a Con Edison Truck rolling down a gentle hill. However the National Ignition Facility is meant to test colossal forces in tiny, manageable packages (it is putatively designed to model the extreme temperatures and conditions of nuclear weapons without requiring actual nuclear testing).

The real purpose of the National Ignition Facility is to try to leapfrog the moribund engineering quest for usable fusion energy. I wrote an overly optimistic piece about the place over a decade ago and have barely heard anything about it since then aside from a story about how they finally got their laser array to work right back in 2012. To briefly recap the methodology of this process, here is a simplified description. Scientists fire a burst of extremely intense energy through the futuristic laser array for 20 billionths of a second. This energy is theoretically meant to vaporize a small gold capsule containing deuterium and tritium. If lasers strike the gold correctly, the disintegrating gold releases a high-energy burst of x-rays which compact the capsule and force the hydrogen isotopes to fuse. On August 8th, for the first time, this process mostly worked and the reaction actually yielded 70% of the energy used to fire the lasers (an enormous improvement from the previous 3% maximum which had been the benchmark for years).

Apparently the breakthrough involved improving the size, shape, and microscopic surface preparation of the capsule (classic engineering stuff!). Nuclear engineers are quick to point out that the result still leaves us a long way from figuring out how to produce the clean abundant energy which humankind desperately needs to solve our (rapidly growing) problems and needs. Yet they also have a long-absent glint in their eyes and a new spring in their step. This is real progress in the search for a goal which has proven maddeningly elusive. Let’s keep an eye on the National Ignition Facility, and, maybe, just maybe this would be a worthy place to spend some more of our national budget.

Ye Olde Ferrebeekeeper Archives

August 2021