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Laser Fusion Passes Major Hurdle

chill writes "The National Ignition Facility at Lawrence Livermore National Laboratory has performed their first controlled fusion experiments using all 192 lasers. While still not ramped up to full power, the first experiments proved very fruitful. The lasers create a lot of plasma in the target container and researchers worried that the plasma would interfere with the ability of the target to absorb enough energy to ignite. These experiments show that not only does enough energy make it through, the plasma can be manipulated to increase the uniformity of compression. Ramping up of power is due to start in May." The project lead, Dr. Sigfried Glenzer, is "confident that with everything in place, ignition is on the horizon. He added, quite simply, 'It's going to happen this year.'"

10 of 354 comments (clear)

  1. Re:So... by Lord+Byron+Eee+PC · · Score: 5, Insightful

    Clean, safe, American-made, no foreign oil, low level of pollutants, and a reasonable amount of entropy (heat) released. Sounds like a winner to me.

  2. Re:So... by CRCulver · · Score: 5, Insightful

    However, just as with fission, it's likely nothing will be built without massive amounts of subsidy, and it will pay off only in a span of decades. Unless the public and officials are willing to think longterm, fusion is going to be delayed regardless of whether the technical hurdles are overcome.

  3. fusion has radioactive waste by circletimessquare · · Score: 4, Insightful

    but its low powered and has quick half-lives. additionally, there are no geopolitical overtones concerning fuel sources: you just need sea water. no climate changing pollution/ city-choking smog for that matter. no peak oil this or that, no bubbles and spikes in supply or pricing

    additionally, if everyone had electric cars, there would be no petrodollars funding saudi arabia, a backwards fundamentalist regime that funds wahhabi madrassas in places like pakistan, that give rise to all of these well-funded (from saudi "charities") militant assholes in the muslim world

    no funding of gas bag chavez in venezuela, no funding of neoimperial russia and putin, no funding for nigerian graft and corruption...

    it will take a long time, but if we can remove the reason for the world to have any vested interests in backwards regimes, propping them up and preserving them unnaturally, and we instead let these regimes instead rise and fall on their own intrinsic value in governing fair societies, then we will have taken a mighty step forward in terms of progress in this world

    of course, it will be decades before we're all driving electric cars powered by fusion plants. but one can dream, cant' they?

    --
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  4. Re:So... by ElSupreme · · Score: 5, Insightful

    What is wrong with a pay off in decades. This "profit now" attitude is going to kill America. You think the interstate system paid off sooner than decades? You think the interstate system was a failure?

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  5. Re:So... by delinear · · Score: 4, Insightful

    What's really scary, being a kid at the time the movies came out, is that pretty soon the "future" they visit in the second movie will be our past (we're only five years away)...

  6. Re:So... by amplt1337 · · Score: 4, Insightful

    You think the interstate system was a failure?
    Well... given that the existence of the interstate infrastructure created the incentives that destroyed the locomotive as the main means of in-land shipping in America, and in other ways promoted the reliance on the automobile that's ended public transit in most areas and greatly exacerbated global warming... possibly yes. : p

    But I think the parent's point was actually the same as yours -- cynicism about Everybody Else's willingness to do something that'll have a profit after the next quarterly earnings report.

    --
    Freedom isn't free; its price is the well-being of others.
  7. Re:Yes, but is it REALLY working? by Dr_Barnowl · · Score: 4, Insightful

    And can it sustain power generation?

    You're talking about zapping a very small, supercooled, gold-uranium alloy target with a beryllium sphere containing about 1mg of DT fuel, about 10 times a second.

    Have a thought experiment about the engineering involved

    • Producing the "ammunition" - bear in mind that tritium is one of the rarest and most expensive substances on earth[1]
    • Positioning it and aligning it - ten times a second
    • Charging and firing the most powerful laser array on earth - ten times a second
    • Somehow removing the heat from the reactor vessel without impeding the laser paths

    what quantity of nuclear waste will such a machine produce?

    DT fusion produces fast neutrons, so some. You're looking at much shorter half-lives ; the reactor core will have the same activity as coal ash after about 300 years.

    And will ITER be quickly refactored to take this into account?

    ITER is a totally different design, so no. I think ITER is a far more credible design than laser-fusion, given that the engineering challenges seem some orders of magnitude easier.

    NIF is just a testbed for nuclear fusion, without the inconveniently illegal use of real nuclear weapons.

    [1]

    If you're firing at 1mg of fuel, by mass, 3/5 of it is Tritium or 0.6mg so (60 * 60 * 24) seconds in day * 10 per second * 0.0006 g = 518.4 g of tritium per day.

    The total production in the USA between 1955 and 1996 was 225kg ; the stockpile in 1996 stood at 75kg

  8. Re:Ignition = net positive energy by pauljlucas · · Score: 4, Insightful

    By definition, when they achieve ignition - there will be a self sustained, fusion reaction - the fusion reaction will sustain itself until its fuel is exhausted.

    AFAIK, this method of fusion is not nor will ever be self-sustained -- it simply doesn't work that way. You have to repeatedly fire the laser, once per fuel pellet. Once the pellet ignites, energy is released. After it's released, the pellet is exhausted. To release more energy, you have to insert a new pellet and repeat. It's not like there's a lot of fuel at the focus of the lasers that just needs one firing to ignite the fuel and it will chain-react. The only way to have a chain-reaction sustain itself with no input of energy would be to have the fuel at the high pressure and high temperature that's found at the core of a star. The laser temporarily creates a tiny spot of such pressure and temperature, but there's no way the reaction can sustain itself without repeated firing of the lasers.

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  9. Re:So... by HeckRuler · · Score: 5, Insightful

    Don't worry, as soon as anything explodes, someone dies, or they find a "scientist" who can worry and fret, Foxnews will point out how Obama's DOE is funding crazy apocalypse engines.

  10. Re:So... by rhsanborn · · Score: 4, Insightful

    Unfortunately, we need a populace that is capable of looking to the future as well. Without that, we'll never get the political structure you're describing. People don't vote for politicians who spend money on long term projects.