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Can World's Largest Laser Zap Earth's Energy Woes?

Posted by samzenpus on from the what-could-go-wrong dept.

newviewmedia.com writes "Scientists at the Lawrence Livermore National Laboratory plan on using a laser the size of three football fields to set off a nuclear reaction so intense that it will make a star bloom on the surface of the Earth. If they're successful, the scientists hope to solve the global energy crisis by harnessing the energy generated by the mini-star."

18 of 372 comments (clear)

  1. And nothing could possibly go wrong... by ShadowRangerRIT · · Score: 5, Interesting

    Okay, no, nothing will likely go wrong (at least, nothing dangerous to anyone more than a few hundred yards from the event in the worst case scenario). But damn if this doesn't sound like the opening to the plot of a disaster movie.

    --
    $_ = "wftedskaebjgdpjgidbsmnjgcdwatb"; tr/a-z/oh, turtleneck Phrase Jar!/; print
    1. Re:And nothing could possibly go wrong... by germ!nation · · Score: 5, Funny

      <spoiler>
          everyone dies apart from Bruce Willis
      </spoiler>

    2. Re:And nothing could possibly go wrong... by Anonymous Coward · · Score: 5, Funny

      Well, if the star turns out to be a problem, you can get rid of it with a black hole from the LHC...

    3. Re:And nothing could possibly go wrong... by Walterk · · Score: 4, Funny

      At the very least this is one laser you don't want to look into with your remaining eye.

      --

      "If anyone needs me, I'm in the angry dome."
    4. Re:And nothing could possibly go wrong... by Anonymous Coward · · Score: 5, Funny

      My question is "Can we find a shark big enough?"

    5. Re:And nothing could possibly go wrong... by j_166 · · Score: 4, Insightful

      How about how the one guy was bitten by a radioactive spider and gained spider powers?

  2. bad journalism by QuantumG · · Score: 5, Informative

    The National Ignition Facility is not doing research into energy production. The research they're doing will not have applications in energy production. The hope is that by understanding ignition other nuclear fusion projects will be able to make better progress.. it is completely pure research, as you would expect from a national laboratory.

    --
    How we know is more important than what we know.
    1. Re:bad journalism by dintech · · Score: 5, Funny

      And from the article

      you'll have to suspend all previous notions about what a laser looks like. This one is basically a giant factory full of tubes.

      Ted Stevens, is that you?

    2. Re:bad journalism by pedestrian+crossing · · Score: 5, Informative

      I remember a physicist saying "The Sun ? Pfah ! Too cold and too inefficient ! If we were to reproduce the conditionss in the sun, we would never get anything that would interest industries !"

      Indeed. From Wikipedia:

      The energy production per unit time (power) produced by fusion in the core varies with distance from the solar center. At the center of the sun, fusion power is estimated by model to be about 276.5 watts/m3, a power production density which more nearly approximates reptile metabolism than a thermonuclear bomb. Peak power production in the Sun has been compared to the volumetric heats generated in an active compost heap. The tremendous power output of the Sun is not due to its high power per volume, but instead due to its large size.

      --
      A house divided against itself cannot stand.
    3. Re:bad journalism by pz · · Score: 5, Interesting

      The National Ignition Facility is not doing research into energy production. The research they're doing will not have applications in energy production. The hope is that by understanding ignition other nuclear fusion projects will be able to make better progress.. it is completely pure research, as you would expect from a national laboratory.

      My understanding from friends who work at LLNL is that it's an open secret that at the NIF they are not working on energy production, but, rather, thermonuclear ignition for weapons research. It's still pure research, in that they're working to produce controlled thermonuclear fusion rather than designing bombs outright, but the purpose of understanding fusion per se is so that we can better understand the current state of our present arsenal as it gets older. At least that's what they tell me.

      So, we have a tiered layer of secrecy about NIF:

      1. for the public: we're doing energy research for a petroleum-free tomorrow
      2. for people who probe: we're doing fusion research to model our ageing weapons stockpile
      3. [ guess the real reason here ]

      I'm betting the third line is only marginally related to the first two, given the history of activity at LLNL.

      --

      Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
    4. Re:bad journalism by Anonymous Coward · · Score: 5, Informative

      If by "pure research" you mean "nuclear weapons research," then you are absolutely correct. I am a nuclear physicist who has done some work for the NIF project. This is a big make-work project for otherwise the otherwise unemployed nuclear weapons establishment. We don't explode nuclear weapons at the Nevada Test Site anymore, but DOE wants to make sure that we can be confident that our aging stockpile of warheads will continue to operate.

      Part of the project's justification is its potential use as a scientific user facility. A big pulse of 14 MeV neutrons could be valuable for all kinds of nuclear science experiments. But that's a sideshow. Another part of the project's justification is the potential of inertia driven fusion as an energy source. To get a 600 MWe power plant out of NIF, you'd have to implode a capsule something like 10 times per second. That would involve dropping a stream of target pellets into the chamber and having the lasers target them, and hit a falling object simultaneously. Right now, the targets are individually placed at the precise center of the chamber and the lasers are fixed to aim at that point. NIF will fire perhaps twice per day once they get the bugs shaked out, and the laser people convince themselves that the lasers won't destroy themselves each time they are activated.

      Assuming we can overcome those hurdles, then we have the problem of converting a burst of 14 MeV neutrons into usable energy. In a fission reactor, the (charged) fission products carry most of the energy. Being charged, they interact strongly with the fuel. Collisions transfer the energy to the fuel, the fuel heats up, and the flowing water removes the heat from the fuel to make steam and turn a generator. How do you get those uncharged neutrons to deposit their energy in a small volume of material (diffuse heat is useless heat)? Several solution have been proposed, but there are potential problems with each of them.

      Assuming those problems can be fixed, where are you planning to get enough tritium to fuel the thing? NIF's Ignition Campaign is centered around D+T fusion. Tritium is a byproduct of fission reactor operations, but if you need a multi-billion-dollar fission reactor (1,110 MWe) to supply a multi-billion-dollar fusion reactor (600 MWe) with fuel... why not just build two fission reactors and devote the savings to reprocessing or disposing of the spent nuclear fuel?

      In short, Fusion is the power of the Future! (And always will be.)

      To say we're a long way from a viable power plant

    5. Re:bad journalism by Maury+Markowitz · · Score: 4, Interesting

      > I recall reading that the NIF is the first stage of a prototype
      > for an actual method of producing steady thermal power
      > from fusion, i.e. a viable electricity source.

      LLNL has been saying this for years, but it's never been true.

      The primary purpose of the NIF is to give the bomb-making establishment something to do so all the physicists won't find real jobs. I am not making this up, it's well recorded and easy to verify.

      The justification they release into the defence establishment is that NIF will be used to tune the hydrodynamics code they use to design h-bombs. Everyone outside LLNL dismisses the need for such a project, and the other weapons labs (like LANL and Sandia) have been particularly scathing.

      To the public, LLNL releases a stream of reports about "unlimited power" and such, but calculations made over 30 years ago demonstrated there is no hope for this. At best, with completely new solid-state drivers, you might be able to get 1/10th the power out that you put in, BEFORE conversion from thermal to electrical. ... with the current designs. Look up HiPER.

      Maury

  3. Funding... Anyone? by digitalchinky · · Score: 5, Insightful

    Quote: We have a very high confidence that we will be able to ignite the target within the next two years...

    So basically it'll never happen. Haven't they been saying this for the last 20 years?

  4. Wanted... by Heed00 · · Score: 4, Funny

    One frickin' huge shark.

    --
    Thought thinks itself.
  5. Re:When will we quit generating steam for power? by Dr_Barnowl · · Score: 4, Informative

    Despite it's earlier mention in the thread, I have to take the opportunity to point out that Focus Fusion involves a reactor design that extracts power from the reaction via 2 routes ;

    • Direct induction of current by a stream of helium ions
    • Gamma-voltaic collector

    Both of which are very much more direct than steam generation. I believe the reaction has plenty of waste heat which could be used industrially as well.

  6. Re:The BBC did this much better, back in January by Mindcontrolled · · Score: 4, Funny

    Hey, don't complain - usually we just link to a blog, which links to another blog linking a twitter feed with a tinurl-obfuscated link to another blog finally linking to a tabloid article. When you worked yourself through that link chain, you have all the information you need to google for the original source, which, of course, is behind a paywall.

    --
    Ubi solitudinem faciunt, pacem appellant.
  7. I wonder by xednieht · · Score: 4, Funny

    If the laser is the size of 3 football fields how big does the shark have to be?

    --

    Hope is the currency of fools
  8. Re:Fusion power dream by Dr_Barnowl · · Score: 5, Informative

    This article concentrates on Deuterium-Tritium fusion, and I agree with it in that context.

    Most of the concerns are addressed by the design of a DPF reactor.

    withstand temperatures of millions of degrees for years on end

    That's just FUD, I'm afraid. Even in tokamak reactors, the plasma is kept separate from the reactor vessel. The plasma is at millions of degrees ; the reactor vessel is not. In a DPF reactor, the plasma is a teensy little 12 microns across - even if the contents are running at about a billion Kelvin, they won't heat the reactor vessel to millions of degrees. The reactor is also designed to emit most of it's energy through non-thermal vectors.

    constantly bombarded by high-energy nuclear particles

    True, in a DT reactor. Not so true in a pB reactor - the reaction produces helium and electrons, not neutrons.

    has to make its own nuclear fuel

    This one is the big winner. As they rightly noted, tritium is one of the rarest elements on Earth. A pB reaction uses no tritium, it uses common or garden "normal" hydrogen, and boron, an element that's abundant enough to sell as eyewash.

    no outages, interruptions or mishaps—for decades on end

    When a 1 GW reactor goes offline, yes, you have a shortfall problem. When the proposed 5MW output DPF reactor goes offline for it's routine maintenance (for about 12 hours), you just lean on the others you have running. Lots of small, local, redundant reactors the size of shipping containers make for more reliability than a few whacking great behemoths the size of aircraft carriers. When they cost $300,000 instead of $10,000,000,000, you can afford to pile them high, and sell them cheap.

    must also convert energy from the neutrons into heat that drives a turbine

    The design is intended to use 2 methods of direct energy collection that are not heat engines, a more elegant and efficient solution that places it closer to "power plant" break-even.

    At least they report the purpose of NIF correctly, albeit couched in soft language - it's about "National Security", not energy generation.