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Power Shark United States Science

Laser Fusion Put On a Slow Burn By US Government 143

gbrumfiel writes "Those hoping to laser their way out of the energy crisis will have to wait a little longer. The U.S. government has unveiled its new plan for laser fusion, and it's not going to happen anytime soon. It all comes down to problems at the National Ignition Facility (NIF), the world's most powerful laser at Lawrence Livermore Lab in California. For the past six years researchers at NIF have been trying to use the laser to spark a fusion reaction in a tiny pellet of hydrogen fuel. Like all fusion, it's tougher than it looks, and their campaign came up short. That left Congress a little bit miffed, so they asked for a new plan. The new plan calls for a more methodical study of fusion, along with a broader approach to achieving it with the NIF. In three years or so, they should know whether the NIF will ever work."
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Laser Fusion Put On a Slow Burn By US Government

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  • by rubycodez ( 864176 ) on Tuesday December 11, 2012 @06:29PM (#42254811)

    only Sandia's z-pinch machine and the polywell are looking even remotely promising anyway. ITER is a toilet for flushing down money

  • Pointless anyway (Score:2, Interesting)

    by Maury Markowitz ( 452832 ) on Tuesday December 11, 2012 @07:10PM (#42255107) Homepage

    Fusion is not going to happen. Ever.

    In this case I can get more specific:

    The NIF is physically limited to shots up to about 50 MJ. To put that in more familiar terms, that's about 14 kWh.

    At current baseload prices here in Ontario, about 3.5 cents/kWh, that shot is worth about 50 cents. That's assuming that we convert it entire to electricity, which is of course impossible. A more realistic conversion with 25% thermal efficiency gets us 15 cents of power.

    The fuel target costs tens of thousands of dollars.

    $10,000 >> 15 cents

    Anyone see a problem here? And don't wave this away, we literally have absolutely no idea how to make the fuel cost less than the power is worth. None whatsoever.

    And that's not the only one, of course. The beamlines feed about 1.8 MJ of UV laser light into the chamber. That is generated from 4 MJ of IR in the main beamlines. That's fed from 350 MJ of electrical power. To get 50 MJ out.

    350 MJ >> 50 MJ >> 15 MJ of electricity after conversion

    So there's that too. At current efficiencies, you're better off burning money.

    We have some febrile ideas about how to get this improved by a factor of 10, or maybe even 100. But that's still *below* energy break even. And we don't need break even for this to be practical, we need 10 to 100x.

    This is never going to happen. It's a weapons program, always was. Testing we don't need for a weapon we don't want.

  • by Maury Markowitz ( 452832 ) on Tuesday December 11, 2012 @07:17PM (#42255167) Homepage

    "This is about creating a clean, reliable, cost effective energy solution."

    We already have those, and they actually work and generate profits.

    This doesn't work, possibly won't ever work, and can't possibly be profitable.

    John Nuckolls, the guy that pretty much single-handedly drove ICF research through LLNL, was presented with this problem when the concept was first seriously presented in the early 1960s. At the time he thought the fuel loads could be sprayed from an atomizer and costs fractions of a cent. The next 50 years of experimentation conclusively demonstrated this is *simply not possible*. Not "it's an engineering problem", but "not possible". Curing the Rayleigh instabilities requires target perfection that costs thousands of dollars a shot. And those shots can only ever return pennies worth of power.

    Do the math yourself. And when you do, compare it to current wind prices at 5 to 6 cents/kWh, solar around 10 to 15, or hydro at 1 to 2. There's more than enough of those three to produce every erg used on the planet, and they actually work, right now.

  • Re:Wait, what? (Score:4, Interesting)

    by Dr. Eggman ( 932300 ) on Tuesday December 11, 2012 @07:45PM (#42255393)
    Tiny compared to most things on day-to-day human scales. Here's an image [] of the pellet.

    As for the reaction itself (and I probably have this wrong, so please correct me if you discover so) it would, best-case, generate 100-150 MJ, but I read the target chamber's design only allows for 45 MJ (realistic expectations, I suppose?) That amounts to 11 kg of TNT (yes this is all paraphrased from Wikipedia.) Certainly tiny by the standards of fusion/fission, but quite huge considering the pellet above.

    This might not seem like much, but it is a demonstrative design. Going for designs that would produce a practical commercial system at appreciable outputs would have been astronomically more expensive. Better to prove the concept first. Still more, this is a dual purpose facility; it's primary objective is stockpile stewardship. The potential for fusion research for commercial purposes is just added value.

Only God can make random selections.