5 HN users recommended this explainer4 months2022–2025score 4.5
Years with an HN recommendation, 2007–2026
It is the go-to accessible explainer whenever HN discusses Helion or alternative fusion designs.
Real Engineering's Brian McManus explains Helion's approach to nuclear fusion: colliding two plasma rings, compressing them magnetically, and capturing energy directly from the changing magnetic flux rather than boiling water. It covers why this pulsed design sidesteps problems of tokamaks and laser fusion.
“I recommend you watch this excellent video by Real Engineering” (HN, 2023)
Video regarding Helion that sama just posted: [this video] . Note that Helion says it can get D + D to work, which eliminates much of the OP's concern about tritium. The company is also hiring: [link] I do not personally have the ability or knowledge to independently evaluate claims, but the history of "it will never work" for something that does not outright violate the laws of physics as we understand them is notable too.
Explains Helion's fusion approach, including D+D operation.
I'm far more excited by the innovative Helion fusion design, which unlike the NIF is intended for commercial use, and is in an advanced stage of development. NIF seems more like a way to conduct military related nuclear physiscs research rather than intended/suitable to ever be used for power generation. [this video] Helion seems far more practical than the Tomahawk designs such as ITER, which seem they'll be too expensive to compete with solar/wind.
Presents Helion as a practical commercial fusion design.
There's a fusion startup called Helion near Seattle working on this, it'll be really exciting if it pans out at scale. This video was a fascinating watch: [this video]
Regarding fusion - have you seen Helion’s approach? [0] It seems their approach removes many of the issues with Tokamak or Laser Pulsed fusion. It also reduces most of the feedstock issues with the two part fuel breeding approach. Their approach seems easier to be optimistic about. [0] [this video]
Describes Helion's approach avoiding tokamak and laser fusion issues.
Helion and similar methods side-step the issue by using (mostly) aneutronic fusion. [this video] [link] Also, discussing solar and wind without discussing the base load/storage problem skews the discussion towards solar/wind. Steam plants don’t face those challenges in the way those two do; storage is as much a challenge for solar as steam is for nuclear.
Too late to edit, but my source on the 2 months comment comes from an interview with Helion, who I think made the front page a couple of weeks ago, but in summary they are trying to smash two plasma balls together and then directly capture the magnetic flux created by the resulting fusion, rather than using a heat engine: [this video] They talk about why ITER has no viable fuel source, and about how they (Helion) are going to have to run two configurations of fusion plants in order to source their own fuel. One that produces a 10% power surplus, undesirable neutrons and the fuel for their power plants. They didn’t say anything but I suspect they’ll end up coming up with a use for the neutrons, perhaps making fuels for other processes. Someone will likely eyeball that waste heat as well.
Interview-style source on Helion's plasma collision and direct energy capture.
Watched the Helion Learn Engineering video, too: [this video] Has that net-positive finding been reproduced yet in any other Tokamoks? How does this compare to Helion's (non-Tokamok, non-Stellerator fusion plasma confinement reactor) published stats for the Trenta and Polaris products? Could SYLOS or other CPA Chirped Pulse Amplification lasers be useful for this problem with or without the high heat of a preexisting plasma reaction to laser pulse next to? [link]
Yes they do exist, link elsewhere in this thread, Helion have a 7th generation nuclear fusion reactor fusing once every ten seconds or so. [this video] (It's not surplus of power, but it is repeatable fusion actually happening).
We have that part covered; though unclear that we could get four systems into close enough proximity without negatively impacting each other. [this video] Still, if it allowed for more complete burning and/or less power input per axis…
Helion Energy [link] : > They are developing a magneto-inertial fusion technology to produce helium-3 and fusion power via aneutronic fusion, [2][3] which could produce low-cost clean electric energy using a fuel that is derived exclusively from water. [4] Here's the part of the Real Engineering video where it is explained how 3He and 4He Helium isotopes are fusion byproducts and fuel used to generate electricity with nuclear fusion: [this video] (From "When Will Fusion Energy Light Our Homes?" (2023) [link] ) Doesn't this new nuclear fusion process also change the valuation of the Tritium in [Fukushima Daiichi,] heavy water? Why would you dump money into the ocean?
Explains how helium isotopes act as fusion fuel and byproduct.
I just realized it's THAT Helion. Their fusion experiments are not without controversy. Here's a video on explaining how it works: [this video] And here's a video explaining what's wrong with the scheme: [link] But the TLDW version is that environment required for fusing He3 with deuterium also leads to deuterium fusing with itself, a reaction that creates neutron radiation that irradiates its environment.
No, there are multiple projects and companies that are making good progress toward commercially practical fusion reactors. Helion Energy has a contract to deliver Microsoft a fusion reactor by 2028. It's only four years away so we don't need to speculate about it. Helion will either deliver or they won't: [link] [this video] [link] MIT's Commonwealth Fusion Systems has started construction of their small scale SPARC reactor. Once that has proven itself they will build a larger scale ARC reactor. They should get to first plasma in 2025: [link] [link] [link] [link]
The steam reactor I guess you might be describing is tokamak, which i agree will be a dead end technology. There are interesting small fusion reactors that skip the steam step. They compress plasma magnetically, and when the fusion happens, the expanding plasma in turn expands the magnetic field, and the energy is harvested directly from the field. No steam and turbines. Here is the video where I learned about it: [this video] Maybe any physicists in this thread could share insight on how feasible this is? Your main point stands of course: this is a moonshot project, and solar works TODAY!
Explains compressing plasma magnetically and harvesting energy directly, no steam.
They've been through a few generations of test machines. They have something called "Polaris". It was supposed to be finished around the end of 2024.[1] Their own site still talks of it as being under construction. Discussion on Reddit.[2] They previously built something called "Trenta".[3] That generates two balls of plasma and fires them at each other. There's no fusion or fusion fuel. It's a test rig for plasma generation and manipulation. That was running two years ago. "Polaris" is a scale-up of Trenta, with something to fuse, and with energy recovery. It's very unclear how far that project has progressed. If they were getting energy out, that would be big news. Helion is vague about how that's progressing. [1] [link] [2] [link] [3] [this video]
Or the fact that Microsoft believes they have cracked *fusion* power. Sun in a bottle. Microsoft is breaking ground in WA state building a new fusion reactor. [link] EDIT: Adding description to video link Video from Real Engineering showing Helion's Pulsed Compression Fusion reactor prototype (2022). The same kind of reactor Helion is building in WA state for Microsoft. [this video]
Shows Helion's pulsed compression fusion prototype from 2022.
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