6 ms·

Video regarding Helion that sama just posted: https://www.youtube.com/watch?v=_bDXXWQxK38 https://www.youtube.com/watch?v=_bDXXWQxK38. Note that Helion says it

Video regarding Helion that sama just posted: https://www.youtube.com/watch?v=_bDXXWQxK38 https://www.youtube.com/watch?v=_bDXXWQxK38. 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: https://blog.samaltman.com/helion-needs-you https://blog.samaltman.com/helion-needs-you 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.

tedd4u 4y ago
Yesterday's discussion on that video (form Real Engineering) https://news.ycombinator.com/item?id=34029426 https://news.ycombinator.com/item?id=34029426
- pitaj 4y ago
  I'm really surprised this didn't get more engagement given the massive engagement with pretty much any other fusion story here.
  - tedd4u 4y ago
    Agreed! AFAIK much of that video was news.
- pfdietz 4y ago
  More comments on Reddit. https://www.reddit.com/r/fusion/comments/zo9831/the_real_engineering_channel_at_helion_showing/ https://www.reddit.com/r/fusion/comments/zo9831/the_real_eng...
- mycall 4y ago
  I wonder if future iterations of this use more than two chambers for ever more power, perhaps eventually converging into a sphere shape for the reactor (many years from now).
PartiallyTyped 4y ago
Helion's CEO is doing quite a bit of outreach; I have seen him participate in all sorts of different videos in channels hosted by educational youtuber like [1], and "Real Engineering" in the sibling comment. [1] https://www.youtube.com/watch?v=xsikwXnUcBs https://www.youtube.com/watch?v=xsikwXnUcBs
pfdietz 4y ago
For a while now I've been saying Helion is the least dubious of all the fusion efforts. Their approach cleverly avoids or strongly ameliorates some of the serious engineering/economic issues that face the DT approaches. Interestingly, I am told Helion looked at using their scheme for DT fusion and concluded it would be more expensive than going to advanced fuels, since it would require heat -> electricity conversion in turbines and rotating generators. Will this still be too expensive to compete with renewables? Quite possibly, but I think it's more than attractive enough to spend the money to find out. I'm glad Helion seems to have broken into that exponentially increasing mindshare hype phase. It's going to be interesting waiting for Polaris to come online in 2024. It's also going to be interesting see the effect on other fusion efforts. I suspect this is good news for the other FRC competitors (TAE, Princeton Fusion Systems). Possibly it will not be good news for the more staid traditional approaches, like those using tokamaks.
- moloch-hai 4y ago
  If Helion ends up powering outer solar system probes, that wouldn't be so bad.
- Retric 4y ago
  Helicon is as far as I can tell the least likely fusion effort to actually succeed because they are making serious hype without producing any data to actually back it up. As well as making some wild claims that don’t match up with reality. A single advancement is vastly more believable but when they are suggesting so many advantages such as not needing tritium or steam turbines the most likely thing is for them to just be lying. At a more practical level, any device actually producing non trivial amounts of fusion using helium 3 would quickly make the device extremely radioactive from all the high energy protons being produced. PS: DD fusion produces H3 half the time, it also produces tritium the other half which isn’t generally going to be a waste product it’s going to fuse in the reaction chamber filled with D producing very high enegry neutrons.
  - pfdietz 4y ago
    "Helicon". I hope that's an accidental mispelling, not libel. Why exactly do you think they need to provide public data? They're a company, not academics. They've provided data to their funders, who have also had external experts review the results, including the famous JASON physicists. The result of this got them $500M for Polaris and another $1.7B conditioned on the success of that machine. My impression of Helion is from when I thought their ideas didn't work. This invariably ended up being because I had some misunderstanding of what they were doing. When I thought of a concern, I would find they had already addressed it. This makes all of the things they're doing ring very true. Maybe it will end up not working, but it's not because of anything obvious. Your comment about high energy protons is wrong. The fraction of MeV-scale protons that will undergo a nuclear reaction in a target is very small and drops to essentially zero if the material has high atomic number (because the Coulomb barrier is too high). The induced radioactivity from the protons will be negligible in a properly designed system. About the tritium: the pulse in Helion's design is so short that the tritium nuclei do not have time to thermalize. At the energy they are initially produced the DT fusion cross section is about an order of magnitude smaller. So, most of the T (I'm estimating all but a few percent) will not fuse before the pulse ends. If they have a gas with a low D:3He ratio, DT fusion is suppressed even more. They appear to planning a scheme where there are DD reactors that make 3He, and then D3He reactors that consume it. The latter could be designed with a much more favorable neutron environment.
ridgeguy 4y ago
A brief look at Helion's site indicates their technology requires He3 in the fuel mix. He3 comprises only about 10e-6 of natural helium, which itself is not exactly common. Is needing He3 more or less of an issue than needing tritium?
- kemiller 4y ago
  Their process creates the He3 from deuterium. That’s the secret sauce. They’ve got an interesting model and the direct energy capture approach invalidates much of OPs point. We will see though.
- mycall 4y ago
  He3 is abundant on the Moon imho.
  - moloch-hai 4y ago
    It is not. It would take more energy to extract lunar ³He than could be got by fusing it. In principle, input energy could be intermittent solar, but it is still a losing proposition.

tedd4u 4y ago

Yesterday's discussion on that video (form Real Engineering) https://news.ycombinator.com/item?id=34029426 https://news.ycombinator.com/item?id=34029426

pitaj 4y ago
I'm really surprised this didn't get more engagement given the massive engagement with pretty much any other fusion story here.
- tedd4u 4y ago
  Agreed! AFAIK much of that video was news.
pfdietz 4y ago
More comments on Reddit. https://www.reddit.com/r/fusion/comments/zo9831/the_real_engineering_channel_at_helion_showing/ https://www.reddit.com/r/fusion/comments/zo9831/the_real_eng...
mycall 4y ago
I wonder if future iterations of this use more than two chambers for ever more power, perhaps eventually converging into a sphere shape for the reactor (many years from now).

PartiallyTyped 4y ago

Helion's CEO is doing quite a bit of outreach; I have seen him participate in all sorts of different videos in channels hosted by educational youtuber like [1], and "Real Engineering" in the sibling comment. [1] https://www.youtube.com/watch?v=xsikwXnUcBs https://www.youtube.com/watch?v=xsikwXnUcBs

pfdietz 4y ago

For a while now I've been saying Helion is the least dubious of all the fusion efforts. Their approach cleverly avoids or strongly ameliorates some of the serious engineering/economic issues that face the DT approaches. Interestingly, I am told Helion looked at using their scheme for DT fusion and concluded it would be more expensive than going to advanced fuels, since it would require heat -> electricity conversion in turbines and rotating generators. Will this still be too expensive to compete with renewables? Quite possibly, but I think it's more than attractive enough to spend the money to find out. I'm glad Helion seems to have broken into that exponentially increasing mindshare hype phase. It's going to be interesting waiting for Polaris to come online in 2024. It's also going to be interesting see the effect on other fusion efforts. I suspect this is good news for the other FRC competitors (TAE, Princeton Fusion Systems). Possibly it will not be good news for the more staid traditional approaches, like those using tokamaks.

moloch-hai 4y ago
If Helion ends up powering outer solar system probes, that wouldn't be so bad.
Retric 4y ago
Helicon is as far as I can tell the least likely fusion effort to actually succeed because they are making serious hype without producing any data to actually back it up. As well as making some wild claims that don’t match up with reality. A single advancement is vastly more believable but when they are suggesting so many advantages such as not needing tritium or steam turbines the most likely thing is for them to just be lying. At a more practical level, any device actually producing non trivial amounts of fusion using helium 3 would quickly make the device extremely radioactive from all the high energy protons being produced. PS: DD fusion produces H3 half the time, it also produces tritium the other half which isn’t generally going to be a waste product it’s going to fuse in the reaction chamber filled with D producing very high enegry neutrons.
- pfdietz 4y ago
  "Helicon". I hope that's an accidental mispelling, not libel. Why exactly do you think they need to provide public data? They're a company, not academics. They've provided data to their funders, who have also had external experts review the results, including the famous JASON physicists. The result of this got them $500M for Polaris and another $1.7B conditioned on the success of that machine. My impression of Helion is from when I thought their ideas didn't work. This invariably ended up being because I had some misunderstanding of what they were doing. When I thought of a concern, I would find they had already addressed it. This makes all of the things they're doing ring very true. Maybe it will end up not working, but it's not because of anything obvious. Your comment about high energy protons is wrong. The fraction of MeV-scale protons that will undergo a nuclear reaction in a target is very small and drops to essentially zero if the material has high atomic number (because the Coulomb barrier is too high). The induced radioactivity from the protons will be negligible in a properly designed system. About the tritium: the pulse in Helion's design is so short that the tritium nuclei do not have time to thermalize. At the energy they are initially produced the DT fusion cross section is about an order of magnitude smaller. So, most of the T (I'm estimating all but a few percent) will not fuse before the pulse ends. If they have a gas with a low D:3He ratio, DT fusion is suppressed even more. They appear to planning a scheme where there are DD reactors that make 3He, and then D3He reactors that consume it. The latter could be designed with a much more favorable neutron environment.

ridgeguy 4y ago

A brief look at Helion's site indicates their technology requires He3 in the fuel mix. He3 comprises only about 10e-6 of natural helium, which itself is not exactly common. Is needing He3 more or less of an issue than needing tritium?

kemiller 4y ago
Their process creates the He3 from deuterium. That’s the secret sauce. They’ve got an interesting model and the direct energy capture approach invalidates much of OPs point. We will see though.
mycall 4y ago
He3 is abundant on the Moon imho.
- moloch-hai 4y ago
  It is not. It would take more energy to extract lunar ³He than could be got by fusing it. In principle, input energy could be intermittent solar, but it is still a losing proposition.