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Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

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Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#61

Post by malandrew »

TillE wrote: post #48
ChuckMcM wrote: post #39

Earlier quoted context omitted.

The risk of #3 is that they don't create fusion but they do develop a machine that can emit streams of hot plasma which is then turned into the Navy's weapon of choice for close weapons support on carrier battle groups. That said, I am looking forward to at least one of the fusion efforts bearing fruit. I'm something of an optimist here but I expect a durable solution to the 'energy problem' to emerge from our develo…

We've already weaponized nuclear fusion into the most destructive bomb ever created. It probably couldn't get a whole lot worse than that. I think there are other paths to sustainable energy, but certainly viable fusion power is the holy grail.

I don't understand why this was downvoted. I'm not going to discount the possibility to invent something worse then our most powerful fusion bomb, but if we talk probability here, developing processes that allow greater control is likely to result in a worst case scenario where we have a weapon that is at most as powerful as what we already have, but more focused.

IMHO focused fusion destruction is likely to be far more humane than the indiscriminate destruction caused by the weapons currently in our arsenal. i.e. a highly focused weapon is likely to to result in instant death for the victims instead of minutes to months to years of suffering for victims depending on their exposure levels.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#62

Post by fuddle »

cbr wrote: post #55
bellerocky wrote: post #36

Earlier quoted context omitted.

I don't think mobile fusion reactors are what they're going for. And if you're looking to reduce global carbon emissions try walking, biking or using public transportation. It's true electric cars don't emit carbon the way a fuel based car does, but the production and maintenance of an electric vehicle certainly does.

fusion plant -> mains electricity -> your tesla

Yes that's what I meant, I think this is the future of transport.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#63

Post by scythe »

sbierwagen wrote: post #54

Safe: With no possibility of melt-down, or hazardous nuclear waste, fusion dose not suffer the drawbacks that make fission an unattractive alternative. Eyeroll. D-He3 fusion produces less neutron flux than D-T, but it's hardly aneutronic-- otherwise they couldn't breed He3 from it. After a decade, the whole reactor will be nuclear waste. I wonder what the service interval on an installed reactor will be? Or are they…

>D-He3 fusion produces less neutron flux than D-T, but it's hardly aneutronic-- otherwise they couldn't breed 3He from it.

You can't "breed" 3He; you have to breed tritium, which decays to He3 with a half-life of 12 years. D-3He reactors do produce some neutrons, roughly 1% of the flux of D-T, and almost entirely from D-D side-reactions.

Actually, a big problem with D-3He as of today is the lack of neutrons -- since you only get one neutron per 100 (e.g.) reactions, you can't possibly breed enough tritium to break-even. You have to come up with some other neutron source, or send rockets to Jupiter.

>After a decade, the whole reactor will be nuclear waste.

Fusion reactors are generally made from boron carbide -- a material unique for the fact that it does not become very radioactive when irradiated with neutrons. 14C which is produced can be extracted by oxidation and centrifuging, and in any case is not nearly as scary as, say, 90Sr. No other concerning radioactive isotopes exist with atomic masses between 10 and 21 (cf 22Na).

>commercial helium comes natural gas fields! It's literally a fossil gas, which is why we're running out of it:

Nope, that's 4He. There's basically no 3He in natural gas (because the helium there is radiogenic), so obtaining fuel that way wouldn't work even if we wanted to.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#64

Post by malandrew »

marcell wrote: post #60

Can someone explain why this team is confident that they can build a commercially viable reactor in 3 years? Conventional wisdom is that nuclear fusion is "decades away". What does this team know that others don't?

My bet is either:

(1) They have a solid lead we don't know about; or

(2) Saying you are 3 years away generates hype and interest that keeps netting you the funding to work on something as long term as decades away.

Even if they secretly think it is exactly one decade away, it is in their interest and the interest of the current investors to say it's only a few years away since they will depend on other investors to get piling in on this investment in 1-2 years time.

My advice to anyone working on inventing something truly new instead of putting a startup together from off the shelf parts: Never under-estimate the value of optimism in your time frames and communicating that optimism and timeframe often. Every truly big idea I can think of has depended on a similar optimism since it's the only way to actually net you the amount of money needed to accomplish something truly novel.

Even Kennedy did this when he talked about putting a man on the moon by the end of the decade. It took 8 years, one month and 26 days from the date of his speech to accomplish something that was pretty far fetched in 1961. Only those willing to make bold claims are capable of taking such bold claims to fruition. That's how you raise the money you need and recruit the people you need to make that a reality. Moonshot startups require a moonshot attitude.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#65

Post by Aerospark »

rdl wrote: post #23

It's interesting that you can justify this investment in at least four separate ways, independently: 1) Even if there is a low chance of success, it would be wildly profitable if successful, and investing early gets you a good share if it's successful. 2) Fusion power would make the world a better place; investing in this way, when you already have huge returns and it's someone else's money, is actually rational even…

Well if they really "Developed complete self-supplied He3 fuel cycle" like it says on their website, that is number 3) right there.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#66

Post by sbierwagen »

scythe wrote: post #63
sbierwagen wrote: post #54

Safe: With no possibility of melt-down, or hazardous nuclear waste, fusion dose not suffer the drawbacks that make fission an unattractive alternative. Eyeroll. D-He3 fusion produces less neutron flux than D-T, but it's hardly aneutronic-- otherwise they couldn't breed He3 from it. After a decade, the whole reactor will be nuclear waste. I wonder what the service interval on an installed reactor will be? Or are they…

>D-He3 fusion produces less neutron flux than D-T, but it's hardly aneutronic-- otherwise they couldn't breed 3He from it. You can't "breed" 3He; you have to breed tritium, which decays to He3 with a half-life of 12 years. D-3He reactors do produce some neutrons, roughly 1% of the flux of D-T, and almost entirely from D-D side-reactions. Actually, a big problem with D-3He as of today is the lack of neutrons -- since…

  You can't "breed" 3He; you have to breed tritium, which 
  decays to He3 with a half-life of 12 years.
Huh, I didn't know that. Helion directly claim they've "developed [a] complete self-supplied 3He fuel cycle", though. How did they manage that? Are they just massaging the truth, by saying that warehousing the tritium exhaust for a decade, then putting the 3He back in the reactor, still counts as a closed fuel cycle?

I imagine you could produce 3He by hitting deuterium with a proton beam, (or doing something exotic with 4He, or 6Li) at incredible cost per litre of produced 3He, but that's not really a "fuel" cycle, since the power reaction isn't involved in any way...

  Fusion reactors are generally made from boron carbide
??? Source? I've never seen a vacuum chamber cast from boron carbide, and you certainly can't make magnets out of it, which have to be centimeters away from the reaction, and therefore get irradiated. Are there any running fusion experiments that use internal boron carbide cladding to shield the vacuum chamber walls?

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#67

Post by mkaziz »

malandrew wrote: post #61
TillE wrote: post #48

Earlier quoted context omitted.

We've already weaponized nuclear fusion into the most destructive bomb ever created. It probably couldn't get a whole lot worse than that. I think there are other paths to sustainable energy, but certainly viable fusion power is the holy grail.

I don't understand why this was downvoted. I'm not going to discount the possibility to invent something worse then our most powerful fusion bomb, but if we talk probability here, developing processes that allow greater control is likely to result in a worst case scenario where we have a weapon that is at most as powerful as what we already have, but more focused. IMHO focused fusion destruction is likely to be far m…

This is true, but a focused bomb is also one more likely to be used because you're not laying the countryside to waste using it.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#68

Post by cpihl »

grondilu wrote: post #58

When talking about breaking even, does that include the energy needed to make the deuterium? Or rather to collect it, considering it has to be extracted from water or something. IIRC deuterium costs quite a lot of energy to produce and as a result for a while it was only produced by countries having large amount of hydroelectricity available. Not exactly related, but this made me wonder : inside a tank full of liquid…

That's a good question. The short answer is the energy that it takes to extract D2 from water is so small compared to the fusion energy released it isn't a factor. That is reflected in the cost of D2O at about $0.70 per gram. In a fusion reactor, even with inefficiencies, that gram of D2O will create about $1000 worth of electricity.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#70

Post by malandrew »

kayhi wrote: post #28
sloughj wrote: post #11

Earlier quoted context omitted.

Right now we just buy deuterium off the shelf, it is low cost and plentiful. You can get deuterium by electrolysis of heavy water, see here: http://en.wikipedia.org/wiki/Heavy_water

Perhaps low cost (25L, ~$600) is relative, depending on the purity, but am unsure how much scale a project like this would use.

I wouldn't be surprised if that cost is still a drop in the bucket compared to salaries though. How much deuterium is a startup like this likely to go through in a month?
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