Last December scientists at the Lawrence Livermore National Laboratory achieved the world's first fusion ignition, creating more energy than they used, in a pivotal step toward commercial nuclear fusion: a potentially limitless, radioactivity-free clean energy.
Now, they’ve repeated what U.S. energy secretary Jennifer Granholm described as “one of the most impressive science feats of the 21st century” less than 8 months later.
According to people with knowledge of the results via a Financial Times report, this timeline shows that the pace of progress is increasing. The lab will publish a formal analysis of the results soon.
In the race toward nuclear fusion against the ticking clock of the climate crisis, milestones like this show it may be closer than we think, with private ventures like FootPrint Coalition-backed MIT spin-out Commonwealth Energy Systems scheduled to reach a commercialization stage by 2025, and Jeff Bezos-backed General Fusion by the 2030s.
Last December, the biggest science story of 2022 ended the year with a bang… or rather, an ignition.
Every day scientists at the federal Lawrence Livermore National Laboratory (LLNL) in California fire the world’s largest laser into a tiny capsule with the goal of achieving fusion, the process that occurs in the sun and the stars of heating two hydrogen isotopes to unimaginable temperatures until atomic nuclei fuse together, releasing swaths of helium and thus, what could eventually be boundless energy in the form of neutrons.
However, the first step to boundless energy is net energy gain or ignition. Ignition is the process of producing more energy than the giant laser uses, and in December 2022, Lawrence Livermore scientists achieved this monumental step, in what U.S. energy secretary Jennifer Granholm described as “one of the most impressive science feats of the 21st century.”
Nevertheless, any scientist knows that the name of the game is repetition. Nothing is really proven until it can be accomplished over and over again, proving it's not a fluke, or in fusion’s case, a shooting star.
Now, the Livermore scientists have done just that, repeating their impressive feat, and according to three people with knowledge of the preliminary results via a Financial Times report, the second ignition, which was achieved on July 30, produced an even higher energy output than the December experiment.
“Ignition is a first step, a truly monumental one that sets the stage for a transformational decade in high energy density science and fusion research,” said LLNL Director Kim Budil in a February post from the lab.
“The pursuit of fusion ignition in the laboratory is one of the most significant scientific challenges ever tackled by humanity, and achieving it is a triumph of science, engineering, and most of all, people,” she added, speaking of the December achievement.
Soon, the scientists plan to publish an analysis of the results.
“Since demonstrating fusion ignition for the first time at the National Ignition Facility in December 2022, we have continued to perform experiments to study this exciting new scientific regime. In an experiment conducted on July 30, we repeated ignition at NIF,” the laboratory confirmed in a statement. “As is our standard practice, we plan on reporting those results at upcoming scientific conferences and in peer-reviewed publications.”
Nuclear fusion has been the dream of physicists since the 1950s, and while many scientists still believe achieving commercial fusion is decades away, the back-to-back once-in-a-decade achievements show that the pace is picking up.
The National Ignition Facility at LLNL is a public venture backed by the Department of Energy. Working at the nexus of defense, intelligence, energy, and environmental security, NIF operates the world’s largest and most energetic laser system — the size of a sports stadium. Here, NIF takes a maximum of one laser shot a day. However, to create nuclear fusion to the scale of a power plant, several shots would need to be taken per second.
While NIF does not give an estimated year for when it believes it will be able to achieve commercial fusion to this scale, already, a handful of private nuclear fusion ventures have. One is FootPrint Coalition-backed Commonwealth Fusion Systems (CFS), a spin-off from the Massachusetts Institute of Technology (MIT), which believes that its ARC (Affordable, Robust, and Compact) system will reach a commercialization stage by 2025.
That’s two years away, and so far, the company has raised $2 billion to get there.
Another private venture, General Fusion based out of Canada and backed by Jeff Bezos through his VC arm Bezos Expeditions, has a demonstration plant in the United Kingdom which it aims to have operating by 2025, selling reactors by the early 2030s.
Like CFS, General Fusion’s prototype plant is small, unlike the stadium-sized system at NIF, as many startups try to move away from the gargantuan size that has been indicative of fusion systems for decades, as exemplified by ITER, a multi-country collaboration in France expects viability by 2025 and will begin starting experiments for what’s known as hydrogen fusion by 2035.
Still, NIF has a long way to go.
In December, the reaction produced about 3.15 megajoules, which was about 150% of the 2.05MJ in the lasers. The July experiment produced 3.5 megajoules. For comparison, in the previous record, set by British scientists at the Joint European Torus (JET) facility near Oxford, the team generated 59 megajoules of sustained energy for five seconds. More than doubling a 1997 record, and it would have been enough energy to power 35,000 homes during the five seconds.
These ventures, along with many others, have key similarities and differences when it comes to their approaches, from those which use magnetics like CFS to those that use plasma like NIF, but as they all make progress on their ambitious timelines, NIFs repeat breakthroughs further underscores the possibilities of fusion.
Known as the universe’s choice for an energy system, nuclear fusion is the process that occurs in the sun and the stars, and mimicking it on Earth, whether via magnets or lasers, would mean, as many scientists put it, limitless, clean energy, with no radioactive waste, and most important in the fight against the climate crisis: no carbon emissions… ever.
The race for nuclear fusion is one, and as the climate crisis sets the timer, clearing milestones such as ignition inches us closer to the finish line.
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