To create fusion ignition, the National Ignition Facility’s laser energy is converted into X-rays inside the hohlraum, which then compress a fuel capsule until it implodes, creating a high-temperature, high-pressure plasma. (John Jett and Jake Long/Lawrence Livermore National Laboratory)
Last December, in the early hours of a Monday morning, scientists blasted a diamond-shaped fuel capsule the size of a peppercorn with 192 lasers, producing a controlled fusion ignition that generated more energy than the lasers put into the initial reaction.
The team of more than 100 scientists working with the Lawrence Livermore National Lab had achieved a net energy gain.
The nuclear fusion energy breakthrough six decades in the making could pave the way for incredible advancements in the future of clean power.
“Fusion offers the promise of affordable, abundant, reliable, clean energy. It is the holy grail. We now know that commercializing fusion is less a matter of whether than of when,” said U.S. Secretary of Energy Jennifer Granholm, who toured the lab on Monday.
But the practical application of this — generating power for your home — is likely still decades off.
Kimberly Budil, director of the lab, said that ignition is “truly a game-changing technology,” but its discovery is not the “end of the journey. It marks the beginning of what will be an incredible era of discovery and innovation.”
Here are a few new things we learned about the nuclear fusion breakthrough from the lab’s big press celebration.
Scientists have yet to replicate the reaction
The lab has fired up its lasers five times since its successful experiment, but have not yet had a repeat.
“The little diamond capsules that are the heart of this experiment are extremely difficult to fabricate,” Budil said. “And so we have been using the best capsules available, but we haven’t had the kind of perfect capsule that we had in December.”
Researchers had long struggled to achieve fusion because it requires very high temperature and pressure. It’s comparable to the nuclear reaction that makes stars shine and the sun generate heat and could provide nearly pollution-free, limitless energy if humans can harness it.
The fusion process mashes together two types of hydrogen in water molecules and unleashes a torrent of very clean energy free of any radioactive waste.
The lab has also had to limit the number of very high-energy laser shots they can do in their facility to just eight per year because it can damage the equipment.
They’re experimenting with slightly lower laser energy, but those tests so far haven’t been successful. The lab is working to make the process more predictable and to perfect the targets.
“We have another experiment coming up in about a week that will more closely replicate all of the conditions we had in December,” Budil said. “And we have a number planned for the rest of the year.”
The feds will shell out big money to seed fusion energy start-ups
Granholm said that public-private partnerships will be key to propelling fusion to the next level, and announced a new $45 million grant series from the Energy Department’s Office of Science over the next four years, $9 million of which will be available this year.
Lawrence Livermore’s nuclear fusion achievement is a fantastic proof of concept — they demonstrated it was possible — and can help guide those working to bring this science to practical application.
Granholm said that “this funding opportunity is going to support the creation of inertial fusion innovation hubs, which will draw on the expertise and the abilities, obviously from our national labs, and academia and industry to advance fusion research.”
The US military could be the immediate beneficiary of the fusion breakthrough
The U.S. stopped detonating its nuclear bombs underground three decades ago as a means of testing the weapons. With the fusion breakthrough, the U.S. now has a much safer and less destructive way to evaluate its nuclear weapons stockpile: in a lab. The data from the tests will allow scientists to model what would happen during an explosion.
Avoiding underground testing also supports the U.S.’s nonproliferation efforts, she said.
Lawrence Livermore’s National Ignition Facility made the ignition breakthrough; the feds developed that lab to run experiments on U.S. nuclear weapons without having to detonate them.
NIF’s ignition discovery simulates the uncontrolled fusion of a nuclear bomb explosion, and researchers hope doing this in a controlled lab setting can corroborate their computer models, which they use instead of the live test explosions. It’s a much safer way for them to determine whether their nuclear weapons still work and could prevent them from needlessly replacing them.
“Clearly, as tensions rise abroad, we cannot afford to let our great deterrent lose an edge,” Granholm said. “An ignition gives us a new tool for instilling confidence in our nuclear capabilities.”
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