Viewing 15 posts - 16 through 30 (of 34 total)
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  • #11937
    AvatarJoeviocoe
    Member

    Tulse wrote:

    I don’t think Poylwell is considering Aneutronic seriously just yet. They want a working powerplant using D-T first.

    Frankly I think that is a very wise strategy for them — the first “alt-fusion” approach to reach breakeven will be a big winner, even if it is with more “conventional” radioactive reactions that are nonetheless far easier to produce in principle than pB11. And the Navy is used to dealing with fission reactors, so the radiation from a DT reactor would likely not be an issue.

    I think the Navy is more interested in the promised 100 MW power output. Which is about the same as standard submarine fission reactors. But for a lot cheaper and much better fueling and waste economics.

    The Navy could really benefit from Aneutronic fusion because of the lack of need for sheilding and even better fueling (no need for tritium breeding) and waste (no activation).

    #11938
    AvatarTulse
    Participant

    Joeviocoe wrote: The Navy could really benefit from Aneutronic fusion because of the lack of need for sheilding and even better fueling (no need for tritium breeding) and waste (no activation).

    That’s true, but of all the armed forces they have the least issue with heavy shielding and radiation handling. Their craft can easily deal with both, far more so than the Air Force or Army. (After all, they are the only branch which currently operates nuclear-powered vehicles.)

    I would think the Army would be even more eager for clean, easily-transportable generators (for bases), and the Air Force as well (light enough reactors could power an unmanned bomber for months, and a purely electric plane would have a negligible heat signature).

    #11939
    AvatarJoeviocoe
    Member

    Tulse wrote:

    The Navy could really benefit from Aneutronic fusion because of the lack of need for sheilding and even better fueling (no need for tritium breeding) and waste (no activation).

    That’s true, but of all the armed forces they have the least issue with heavy shielding and radiation handling. Their craft can easily deal with both, far more so than the Air Force or Army. (After all, they are the only branch which currently operates nuclear-powered vehicles.)

    I would think the Army would be even more eager for clean, easily-transportable generators (for bases), and the Air Force as well (light enough reactors could power an unmanned bomber for months, and a purely electric plane would have a negligible heat signature).

    The Army has access to large amounts of petroleum based fuel. So their efforts to have a nuclear program ended early in 1977 and was thought to be a “Solution in search of a problem”. The Navy, especially the submarine fleet, endangers itself when it needs to be resupplied. The Army is does have some recent problems getting constant supplies of fuel… but it is far cheaper and easier to secure petroleum supply and transport than it is to deal with building a Nuclear plant in someone else’s country.

    I don’t think even the lightest of fission reactors would work yet for bombers…
    In such a tight package, the shielding must be thick and heavy to protect the electronics/avionics. Going unmanned doesn’t remove the need for shielding.
    RTG’s mabye. Possibly even battery UAVs recharged from ground or space via microwave.

    #11941
    AvatarTulse
    Participant

    I think you may have misunderstood my point, which not that fission is currently practical for the Army and Air Force, but that they would benefit from a light, reasonably portable, high-density power supply (such as Polywell) more so than the Navy.

    In any case, a breakthrough in fusion on the scale of Polywell or DPF would be a huge boon for all the armed forces.

    #11942
    AvatarIvy Matt
    Participant

    Joeviocoe wrote: They want a working powerplant using D-T first.

    D-D, but I don’t think the U.S. Navy would have much of a problem obtaining tritium.

    #13310
    AvatarMatt M
    Member

    Bussard’s Polywell Fusion Passes a Major Test

    Jaeyoung Park and the team at Energy Matter Conversion Corporation (EMC2) have released a research paper (with videos) discussing the results from a scaled down version of the late Dr. Robert Bussard’s famous wiffleball method of seeking a viable net energy fusion reactor.

    The earlier wiffleballs leaked so much that the reactor couldn’t ever get to producing more power out than went in. But Dr. Bussard’s results encouraged many to offer that with enough energy and pressure against the magnetic field a sharp boundary would form between the magnetic fields and the plasma – so cutting the losses. What the paper reports is validation of the boundary forming, which shows critical progress toward a polywell fusion reactor.

    – See more at: http://newenergyandfuel.com/http:/newenergyandfuel/com/2014/06/10/bussards-polywell-fusion-passes-a-major-test/#sthash.7ju8eqbw.dpuf

    #13311
    AvatarIvy Matt
    Participant

    It’s been a long time coming, but this is very good news. I would compare it to LPP demonstrating plasmoid formation in the DPF and that most of the fusion occurs within the plasmoid. There are some other unsettled questions about the Polywell, but it’s possible many of them have already been answered and will be the subject of further papers. I’m interested to see if EMC2 exercised the option to experiment with hydrogen-boron fuel. I suspect they haven’t got around to it yet, but who knows? Note that the present set of experiments was not intended to produce net gain from fusion. EMC2 estimates that a 100 MW Polywell fusion reactor will require $200 million to design, build, and test. Whether they will obtain that funding through the US Navy or use their published paper(s) to seek investor funding (or both) remains to be seen.

    Jaeyoung Park is giving a seminar at the UC Irvine Department of Physics & Astronomy at 10:45 AM on June 12th.

    #13312
    AvatarIvy Matt
    Participant

    It looks like EMC2 is opening up more now that the Navy contract is concluded. Dr. Park will be speaking at the University of Wisconsin-Madison on Monday, June 16, at 2:30 PM.

    #13313
    AvatarJoeviocoe
    Member

    Ivy Matt wrote: It looks like EMC2 is opening up more now that the Navy contract is concluded. Dr. Park will be speaking at the University of Wisconsin-Madison on Monday, June 16, at 2:30 PM.

    Any video from those talks?

    #13314
    AvatarIvy Matt
    Participant

    I don’t know of anyone who attended the UC Irvine talk. Someone from Talk-Polywell is going to the the UW-Madison talk, but I don’t know whether video recording will be allowed.

    #13318
    AvatarIvy Matt
    Participant

    NBC News has an article on the latest EMC2 results:

    For years, EMC2 Fusion Development Corp. has had to conduct its research into what’s known as Polywell fusion outside public view because the Navy wanted it that way. Now the Navy is phasing out its funding, and EMC2 Fusion is planning a three-year, $30 million commercial research program to see if its unorthodox approach can provide a fast track to cheap nuclear fusion power.

    EMC2 is looking for private investment now. The way I read the article, if they get the funding they need, they’ll attempt to achieve net gain around 2017. They don’t rule out aneutronic fusion, but if their investors want them to go for DD or even DT first, that’s what they’ll go for.

    #13328
    AvatarIvy Matt
    Participant

    A few notes from Dr. Park’s talk at UW-Madison can be found here.

    #13526
    AvatarIvy Matt
    Participant

    News from the Talk Polywell forums: Dr. Park will be giving a talk titled “Polywell Fusion – Electric Fusion in a Magnetic Cusp” at UCLA on Friday, December 5th. See here for details.

    #13554
    AvatarIvy Matt
    Participant

    On January 22, Dr. Park delivered a Microsoft Research talk, titled Polywell Fusion: Electrostatic Fusion in a Magnetic Cusp. It’s an hour and half long, but well worth watching in my opinion.

    The upshot: the Polywell appears to be a viable and attractive fusion reactor. However, it will take time and money to produce a power-generating fusion reactor, but not nearly as much as will be required for a tokamak DEMO reactor. Dr. Park envisions a three-year proof-of-principle research effort to see how the device scales, followed by a $300 million net-power reactor to demonstrate scientific feasibility within a few years. Right now Dr. Park envisions using D-T fuel for the net-power device, but the actual fuel used will be affected by results obtained on the proof-of-principle device. If ion heating efficiency is sufficient (~90%), then he will strongly consider using p-B11 fuel in the net-power device.

    Phase +1: Proof-of-Principle Reactor
    ~3 years
    ~5 ms high-beta operation
    >10-kV ion heating by electron beam injection
    ~$35 million (?)
    Success defined by 1) high-energy electron confinement within a factor of 10 of Harold Grad’s conjecture and 2) minimum (for D-T fuel) 30% ion-heating efficiency via electron beam.

    Phase +2: Net Power Reactor
    a few years
    2m coil radius
    5T magnetic field
    80-kV electron beam
    185 MW plasma heating power
    1.1 GW fusion power (D-T fuel)
    ~$300 million
    Success defined by net fusion power output.

    The presentation slides can be downloaded here. The video of the talk can also be downloaded.

    A thought that occurred to me while watching Dr. Park’s talk is that the Polywell is almost the opposite of the DPF in that it tries to achieve maximum plasma stability (using convex magnetic fields and high-beta cusp confinement) whereas the DPF uses plasma [em]instability[/em] to achieve fusion conditions.

    #13555
    Avatardelt0r
    Member

    These numbers seem very hinky. 1.1GW thermal output can’t be that cheap. Even the switching equipment will cost a lot more. Just a shielding building is going to set you back all of that to be even remotely compliant. And with that much neutron flux you want them to be compliant.

    A 1GW gas power station cost south of 1B. 300M is just not much money. For something of that scale. And no amount of magic can change 1GW no matter how much faith you have.

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