First Light fusion Using Hypervelocity Projectiles for Pulsed Fusion

Startup First Light Fusion (FLF) claims it is on target to achieve fusion gain (more energy out than goes in) by 2024. They are not using lasers or intense magnetic fields which can prove to be very complicated and costly to build. Pulsed power is their main technology. They hope to have reduced the cost and complexity with pulsed power.

Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.

Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.

A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts.  He is open to public speaking and advising engagements.

21 thoughts on “First Light fusion Using Hypervelocity Projectiles for Pulsed Fusion”

  1. Yes, I’ve said before that fusion is a solved problem, they just don’t like the solution.

    The problem is, every other solution looks to be even worse from a cost effectiveness standpoint.

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  2. Sure. You should be able to make that with paraboloid explosives lenses. For two and one point initiation (you don’t want this!) I’m not sure the ratio of speeds between the explosives is where it needs to be for this to be possible. It’s just incredibly impractical.

    In Fatman it was composition B (8050 m/s) and baratol (4900 m/s). The ratio of detonation speeds is ~1.6. The part of the detonation wave going straight from the inititiator towards the pit must can at most be 1/1.6 times as long as the path that goes to the corners of the explosives lens, which goes only through high explosives. So if you had two lenses covering a hemisphere each, the front has to arrive at the “equator” at the same time it arrives at the poles. And that’s not the little dinky plutonium pit; that’s a booster high explosive that envelopes the entire pit.

    In an air lens the steel plate is subsonic; so 8000 m/s vs 300 m/s. The high explosive could run laps around the metal plate before it hits the shell of high explosive around the pit; so you could then trivial make an egg shaped device with the pit closer to the big end that would snap into a sphere as it is launched across the air gap. They went to great lengths to ensure that two points of initiations were required and accidental initiation at only one point would squeeze the PU pit like peanut and avoid criticality (one point safety tests); because one point inititation of a nuclear device should not be a feature, it’s a bug.

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  3. The explosion was triggered from both ends of the Swan device, but the hollow pit air-lens was designed for simultaneous detonation of a HE shell right around the plutonium. I don’t think these guys are putting high explosive in their reactor – though if they put some high-assay uranium in, it would be more likely to reach fusion conditions.

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  4. A version of this has been put into practical use.

    1. Dig underground cavern
    2. Light up a multi-kilotonne nuke
    3. Promise to really think hard and not do it quite so often providing the USA and South Korea give you lots of free food and energy
    4. Profit!
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  5. Fat man, IMO, could have done it with less than six spots, if they’d had a larger volume and weight budget; They used shaped charges and ‘lenses’ to distribute the exterior explosions into a spherically symmetric shock wave, and the less space you have to do that in, the more charges and lenses needed. In Fat Man’s case, they couldn’t get it under 32.

    In principle you could do it with 4, you just need the number of charges to correspond to reasonably regular tiling of a spherical surface, ideally a Platonic solid. But the lens becomes more difficult as the number of charges drops.

    I don’t suppose First Light would want to use 32 rail guns, but six does correspond to a Platonic solid…

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  6. Fat man needed more than six spots to compress.

    On a lighter note I think that a growth industry is definitely capacitor banks.

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    1. Dig big underground cavern
    2. Light Megaton nuke
    3. Harvest energy
    4. Realize that Gen IV fission would have been cheaper

    I’m being cynical but i’d like to think that unicorn powered AI would be able to work out some of the basics of economic cost-benefit calculations.

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  7. I may be wrong on that point, I deduced it from their stating that they had built 1 of six “branches” of the power supply, and the fact that it’s darned hard to compress anything from just one side.

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  8. Only if they don’t due their due diligence. Sales pitch is intended to attract interest. But anyone considering an investment should check into it further. If I didn’t already have a physics degree (which I do), I’d be looking for someone who was an expert to talk to their people and vet the technical details. Typically that would involve signing an NDA, but that’s standard practice for this kind of thing.

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  9. There’s another name for investors that don’t care about the technical details of the fusion projects they’re considering. We call them “marks”.

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  10. OK, so they’re using a high power pulsed power supply to accelerate tiny projectiles, (6, apparently.) to simultaneously strike the outside of a gas filled capsule, compressing it to achieve fusion.

    It’s inertial confinement using high speed pellets rather than lasers or particle beams. The power supply drives the pellets through a rail gun, to achieve 20km/s.

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  11. They are in raising money mode, so presenting at the level of general investors. You notice in the first video he talks about “our machine will need 1000 times less equipment, and we designed it to last longer”, and also talks about their business plan: “we will sell fuel, which is a continuing revenue stream”. These are things investors care about.

    Here on NBF we care more about technical details, and the chances this will actually work, so we are not the audience for these presentations. My takeaway is now I know these guys exist. I can look for news on experimental results.

    In principle the idea should work. It is what is used in H-bombs – collapsing a fission liner with chemical explosives, and the fission reaction collapses the D-T core of the bomb. The trick is doing this in a way that doesn’t destroy your equipment.

    An obvious improvement would be to hit the target from more than one side. That requires more guns, but might reduce the gun velocity to reach fusion levels.

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  12. I am looking forward to when AI using a super universal quantum computer, using self programed simulations, will be able to show us the safest, fastest, cheapest way to Fusion.
    It might even show that a type of process for cold fusion is possible, just not like it is being tried now.

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  13. Their website is worse. The whole thing is written at the level of a bright, but not a science nerd, 12 year old.

    Note: This is no reflection on their actual tech. I’m assuming that the “media relations officer” is someone who is good at photoshop but who knows NOTHING about physics and doesn’t understand what the nerds are talking about. I’m talking about someone who thinks that “fusion is different from fission” is actually something that someone visiting a website about a fusion startup would need to have explained.

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  14. Aarrrghhh…. what a frustrating set of videos.

    They skim along at the junior high school textbook level of explanation. As soon as the tech starts to get detailed they skip to the next section.

    Sounds interesting, but it’s got no meat to the details.

    And skip the first 5-6 minutes of the second video all together. That’s just a primary school level introduction to the high school level explanation. 4 minutes of CO2 is bad mmmkay, with a couple of “what is fusion” minutes after that before he starts with anything that you couldn’t have written yourself from general knowledge.

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