The US government wants to send a small fusion reactor into space and is working with a private company to get a prototype operational by 2027.
Nuclear fusion is a field of physics that scientists have been studying for years because it promises to provide one of the cleanest and most efficient forms of energy possible. Nuclear fusion is when two atomic nuclei fuse into a single heavier nucleus, converting some of the mass into energy.
It’s the same process that powers the sun, compressing hydrogen atoms under tremendous heat and pressure to form helium.
Artificially mimicking this process has proven to be an immensely difficult task. Several elaborate machines have been built that attempt to mimic the conditions at the heart of our sun, from donut shaped tokamaks that use huge magnets to contain the reaction, to giant cannon firing projectiles together† Despite decades of work, nothing has proven to be advanced enough to be built into a power grid.

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Avalanche Energy believes it has the answer with a relatively small reactor called the Orbitron. It works by trapping fast ions in a small orbit around a negatively charged electrode. By creating a small space for this ion plasma — called an ion trap — the engineers behind the Orbitron hope it will provide ample opportunities for paths to cross and merge.
“The smaller it is, the higher the frequency of those orbits, so the more collisions you get,” Avalanche CEO Robin Langtry told me. news week† “So for us it almost wants to be small.”
The tensions required will be enormous, and that is one of the many technical challenges the Avalanche team will have to overcome. If they can, the potential uses for a small reactor could be a game-changer.
“That gives you the idea of a cell, a fusion cell, if you will,” Langtry said. Ultimately, the team thinks these cells could be combined to form a larger fusion battery capable of delivering a megawatt of energy.
This suggests a whole range of possible applications. “As we lower the price, more and more markets will open up for something like this,” Langtry said. “We’re starting at a million dollars per kilowatt, I think because that’s where commercial solar seems to be. Once we get below $100,000 per kilowatt, there’s probably more applications that open up there; aviation is an interesting one, drones “Whatever. And then if you get $10,000 or $3,000 per kilowatt, you start to get competitive with other forms of terrestrial energy, like fuel cells and batteries and stuff.”
One application could be to power spacecraft. In May of this year, the US ArmyThe Defense Innovation Unit (DIU) announced it had awarded contracts to nuclear technology companies in the quest for “next-generation nuclear propulsion and power”. Avalanche was one such company.
The aim of the contracts is to have a successful prototype demonstration in orbit by 2027. The nuclear power sources on board the spacecraft will provide it with the electricity it needs to function and to power an electric thruster.
“Basically, chemical and solar-based systems will not provide the power needed for future DoD missions,” Maj Weed, program manager for the Nuclear Advanced Propulsion and Power (NAPP) program at DIU, said in a press release.
Path to the 2027 launch date
Avalanche Energy’s prototype is still a long way off and currently operates at about 100 kilovolts, slightly less than the record 190 kilovolts achieved in the past with similar technology. Soon they hope to triple this to 300 by using a similar development approach to SpaceX: test, fail, fix.
“We’re trying to do that for fusion, basically trying to build a minimal viable thing, push it to the limit, figure out what’s stopping you from going further, fix it, put it back on the test bench and just a little repeat every day, every week as we go,” Langtry said.
“It’s early times, but there’s certainly a credible path to a 2027 launch date. It won’t be easy, it’s going to be very difficult.
“We have three things we want to do with Avalanche. One is 100 percent carbon-free energy dependency for every country on Earth; we want to accelerate the arrival of a space airline; and we want to make science fiction real. to do it.”