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Comment by ratdragon | Hacker News Reader

What does HN crowd think of companies like hb11 or lppfusion which try to construct much smaller but still powerful (lpp plans for 5MW, relatively small, reactor. They also want to use a different fuel that produces very little neutrons, thus very low radiocativity. And moreover they do not need thermal part as electricity is generated by directly collecting alpha particles (and some Xrays IIRC). It _feels_ to me like ITER is inheritance from old times - trying to build the reactor the way we always did (i.e. thermal; and also using the "easiest" to ignite fuel - but that produces a lot of radiocativity compared to hB11 fuel). As someone pointed out here in comments, there are already better magnets than those used in ITER even now. Don't get me wrong, it would be sooo cool if ITER succeeded and started fusion energy generation, but it is just taking too long.

  https://www.hb11.energy/our-story https://lppfusion.com/technology/fusion-energy-generator/

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I worked on Gene - a gyrokinetics app used to study fusion reactors - and I fondly recall helping a colleague debug one of their simulations in which they set a boundary condition incorrectly; that simulation ran for two weeks before the mistake was found. We estimated this mistake to have costed the tax-payer multiple millions of dollars _in electricity costs_ (just from the core's that were used, their wattage, and the time duration; which is a fraction of the cost of acquiring and operating a super-computer).

All our fusion models that correctly predict all the results produced by all the fusion reactors that have been built to date predict that ITER will work.

I have no idea whether these models predict that these other reactor designs will also work. What I do know is that one needs _many_ simulations to study that, and the costs of doing that feels absurdly out-of-reach for any startup. One does not only need to "verify" a design, but come up with it, optimize it, etc. as well as gaining access to the supercomputing resources or buying and maintaining their own supercomputer. That puts the initial investment already in the millions.

OTOH, a startup that checks a design that has been created, optimized, and verified in academia and whose goal is "only" to build it, would require a smaller investment, but no idea how big this investment ought to be.

Someone below mentioned the following link, in which they do a sharp comparison of fusion technologies. I am by no means an expert, but after watching that link, it appears to me that such solutions are probably unproven science: it took over 50 years to get anywhere near a Q-factor of 1 (energy in = energy out), with hundreds of technologies screened, tested and scrapped.

    https://www.youtube.com/watch?v=L0KuAx1COEk

Fusion scientist here. Hydrogen-boron is 500x harder than deuterium-tritium to ignite, roughly speaking. NIF couldn't even do that. I don't believe that these two groups have hit on the solution. Yes, it would be nice to have aneutronic fusion, but right now we're struggling to get deuterium-tritium to work. One step at a time.

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