Multibillion-dollar projects are slowly moving ahead on the nuclear fusion frontier, but less traditional efforts to harness the power that fuels the sun say they're making progress as well.
In the most basic fusion reaction, molecules of hydrogen isotopes are smashed together under high temperature and pressure to create helium — with part of the hydrogen mass converted into energy, in accordance with E=mc² from Albert Einstein's special theory of relativity. The energy payoff can be immense, as demonstrated by the sun's glare or the blast of an H-bomb. But can the reaction be controlled on Earth?
If the answer is yes, experts say that could lead to a kind of nuclear energy nirvana: plentiful, always-on, relatively clean, relatively low-cost power, fueled by elements extracted from sea water or moon dust. That's part of what's driving the $3.5 billion National Ignition Facility and the $20 billion ITER experimental fusion project — as well as less richly funded commercial ventures.
One venture, California-based Tri Alpha Energy, usually keeps mum about its research. Its support comes from a wide assortment of backers, ranging from Hollywood actor Harry Hamlin to Nobel-winning physicist Arno Penzias to software billionaire Paul Allen to a venture firm created by the Russian government.
Tri Alpha's researchers recently published papers in Physics of Plasmas and Nature Communications that claimed the company's colliding-beam fusion reactor was able to produce high-temperature plasma rings that lasted for 5 milliseconds.
That performance is a tenfold improvement over the containment capability of past research reactors, notes Science's Daniel Clery, author of "A Piece of the Sun," a book about the fusion quest. Clery quotes John Santarius, a plasma physicist at the University of Wisconsin at Madison, as saying Tri Alpha is "moving in a direction that is quite promising."
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Another commercial venture, Canada-based General Fusion, completed a $21.6 million ($27 million Canadian) financing round last month — with Malaysia's sovereign wealth fund as the leading contributor. The investors also include Bezos Expeditions, which is Amazon.com founder Jeff Bezos' personal investment company. General Fusion is working on a concept called magnetized target fusion.
"We expect in the next couple of years to prove out our approach," Canadian Business quoted General Fusion CEO Nathan Gilliland as saying.
$30 million in federal funding
Meanwhile, the U.S. Department of Energy's ARPA-E program is making up to $30 million available for nine projects aimed at finding low-cost pathways to fusion power, as part of a program called ALPHA (Accelerating Low-Cost Plasma Heating and Assembly).
Among the recipients (to the tune of $4 million) is Helion Energy, which is working on an approach similar to Tri Alpha's — that is, field-reversed configuration plasmas. Helion's CEO, David Kirtley, has been quoted as saying that his company could get to the fusion break-even point, where energy output equals energy input, in three years.
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The University of Washington says its researchers have teamed up with colleagues at Lawrence Livermore National Laboratory to win a $5.3 million ALPHA grant for a compact fusion device. The plan calls for scaling up the university's sheared-flow stabilized Z-pinch experiment — a device that could be built up into a commercial fusion reactor.
The big question is whether the geometrically simple Z-pinch configuration can operate at fusion-level temperatures of around 20 million degrees Fahrenheit (11 million degrees Celsius). To find out, the research team will have to boost the system's current and energy by a factor of 10.
Will there be a giant leap?
All this news serves as a "good indicator that the fusion technology community is on the verge of making a major leap forward," Jaeyoung Park, president and chief scientist of EMC2 Fusion Development, told NBC News.
EMC2 Fusion is working on an approach known as Polywell fusion, which combines elements of inertial electrostatic confinement — a technology that comes into play in basement-lab science projects — and magnetic confinement. Park and his colleagues have been receiving funding from the U.S. Navy, but they're working on securing private investment as well.
"The biggest problem we had last year is that people had a lot of doubt about fusion as a viable approach," Park said. As far as he's concerned, a rising tide of interest in small-scale fusion lifts all boats. It also helps that Park and his colleagues are on the verge of having a research paper published in Physical Review X.
Related: Low-Cost Fusion Project Steps Out of the Shadows
Who will sail past the break-even point and onward to commercialization first? As you'd expect, Park thinks it could be EMC2 Fusion. "It's not unrealistic to expect to have a working prototype and get ready for practical fusion in the next 10 years or so," he said.
Other companies — which include Lockheed Martin and LPPFusion as well as Tri Alpha, Helion Energy and General Fusion — no doubt have different assessments of the fusion race. And then there are those multibillion-dollar projects, the National Ignition Facility and ITER, and their potential commercial spin-offs.
Will any of these ventures usher in nuclear nirvana? Or will cheap solar power and next-generation storage batteries make the fusion quest irrelevant? Let's check back in a year ... or maybe five, 10 or 20 years.