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Journal 1ione1's Journal: LTD pushes Z machine forward in the fusion race 220

Sandia Labs has announced, and Energy Daily is reporting encouraging results by adding Russian-developed Linear Transformer Driver (LTD) technology to their Z Machine to solve one of the biggest obstacles to practical fusion reactors. Getting the current needed to "spark" a burst of fusion is do-able. Getting a constant series of "sparks" going to create a continuous chain of fusion bursts has never been achieved. The LTD makes it suddenly look achievable.
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Z Machine Advances Fusion Race

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  • by AvitarX ( 172628 ) <me AT brandywinehundred DOT org> on Thursday April 26, 2007 @10:04AM (#18883969) Journal
    Weren't we closer 30 years ago?
    • Re:20 years off? (Score:5, Informative)

      by aadvancedGIR ( 959466 ) on Thursday April 26, 2007 @10:13AM (#18884107)
      That's the funny thing with science or advanced engineering. Initially, everything looks easy, but the harder you work on it, the more difficulties you understand you will have to deal with. So a) We are indeed closer to a practical solution than 30 years ago and b) we have more realistic timeframes estimations.
      • by rumblin'rabbit ( 711865 ) on Thursday April 26, 2007 @10:17AM (#18884185) Journal
        You're telling this to programmers? The ones who coined the phrase "it's 90% done and always will be"? The ones who invented the software crisis?
        • Actually, I'm a programmer myself and currently working on an embeded driver that is complete and running except for a nasty bug that may cause the whole project to be canceled. And for historical examples more in programming, we can cite sentient AI, which was at hand in the 60's. Plus the space elevator, or the dream of a complete understanding of physics about a century ago.

          Good developpers never commit on dates.
          • Re: (Score:3, Informative)

            Slashdot is News for Nerds, not just programmers.

            According to Bussard [], practical fusion power is nearly as available as the money we decide to put into his system. He specifically says in the video that "the physics is done" --which means that only engineering problems remain.
            • by Gilmoure ( 18428 ) on Thursday April 26, 2007 @11:22AM (#18885239) Journal
              Grue is in the details?
            • by Rei ( 128717 )
              Yes, and his plans are also controversial. Polywell is still something of a long shot. This is really big news, although there are still countless snags that could be hit in such a long development schedule. Also, the twenty years claim is a bit vague -- what sort of milestone are they talking about there? In twenty years, are they looking at the equivalent of the Tokamak-development goals for ITER (the capability to produce more power than goes in -- ~2020-2030), DEMO (actual generation of more power t
          • by metlin ( 258108 )
            I think there is a little computer programmer in all of us - programming by itself isn't particularly hard, it's just the esoteric knowledge that is hard to master. Of course, actual CS is different (graphics, algorithms, machine learning, theory, network algorithms) but programming isn't particularly special.

            Besides, everybody in every area does some amount of programming these days - embedded programming for chips and the like, programming in electronics for FPGAs and ICs, simulation and modelling in phys
    • Re: (Score:3, Insightful)

      by inviolet ( 797804 )

      Weren't we closer 30 years ago?

      Yeah. I came here to make the same quip.

      Then I realized a possible explanation. Perhaps every time another milestone is passed, the new understanding moves us closer to fusion and thus on to the next unexpected hurdle. Sort of like being able to see the second mountain that was previously obscured by the first.

      Or maybe it's just researchers looking to grab headlines in order to obtain more funding. Either way. :)

    • I think the 30 years joke is a bit passe. In realilty, the funding for fusion has suffred some major hits in the last 30 years after the big spike in the 70's. To measure a field's achievment in years is somewhat nieve, as total funding dollars is more realistic. If 1970 funding dollars had continued for the next 40 years, I think we would be there now, but alas we will have to wait for the money to trickle in. Iter is a great step forward, but work in innovative concepts that are alternatives to the to
      • no, you're assuming that problems can be solved by throwing x dollars at it. Today we could have abundant limitless cheap energy if we didn't waste our time on needless sidetracks such as fusion for commercial power. We could have had thorium breeder reactors with sufficient reserves for centuries, and be burning our spent fuel from older reactor designs in them to boot. but no, let's waste our money on pipe dreams and continue the big oil/big corp oligarchy. we're no closer to practical commercial fusi
        • I take it you're speaking of the IFR? I still don't understand why, given the recent spike in interest in non-fossil energy, we're still not building or even talking about them. I mean, (a) fail-safe, (b) radioactive waste safe in under 200 years, (c) far, far more fuel efficient, (d) capable of reprocessing weapons-grade material... what went wrong?
          • From the WP article on the IFR:

            With the election of President Bill Clinton in 1992, and the appointment of Hazel O'Leary as the Secretary of Energy, there was pressure from the top to cancel the IFR. Sen. John Kerry (D, MA) and O'Leary led the opposition to the reactor, arguing that it would be a threat to non-proliferation efforts, and that it was a continuation of the Clinch River Breeder Reactor Project that had been cancelled by Congress. Despite support for the reactor by then-Rep. Richard Durbin (D, IL) and U.S. Senators Carol Mosley Braun (D, IL) and Paul Simon (D, IL), funding for the reactor was slashed, and it was ultimately cancelled in 1994.
            Although Republicans have a reputation for being in the pockets of the petroleum and mining industries, in truth both parties are almost equally opposed to any change in the status quo.

            Fuck "in God we Trust," we should just print "don't rock the boat" on our money.
            • by rbanffy ( 584143 )
              The oil companies have really deep pockets. Together, they can hold an almost infinite number of politicians.
    • by rs79 ( 71822 )
      Fusion is 20 years off from whenever you ask.

  • 20 years! (Score:2, Funny)

    by mdsolar ( 1045926 )
    And to think they said it would be forty years off twenty years ago!
  • 20 years off? (Score:3, Insightful)

    by Firethorn ( 177587 ) on Thursday April 26, 2007 @10:04AM (#18883991) Homepage Journal
    Wasn't it 20 years off 20 years ago?

    I think that I'll stand by my idea that even if/when we crack fusion enough to be able to build a fusion power plant it'll have to be so big to be worth it, that they won't be able to get the funding to do so.

    Basically, Containment costs go up by the square, while energy release goes up by the cube. To make it worth it, we might be looking at a 100 gigawatt reactor*, of which half goes towards sustaining the reaction.

    *1-2 gigawatts is a pretty big reactor today.
    • by tom17 ( 659054 ) on Thursday April 26, 2007 @10:09AM (#18884049) Homepage

      *1-2 gigawatts is a pretty big reactor today.
      You mean 1.21, right?

      • Re: (Score:2, Funny)

        by Firethorn ( 177587 )
        Naw, that'd be 1.21 jigawatts.
    • Fusion reactors could produce some short lived waste, but they are not prone to melt down and so don't need the heavy containment that fission reactors require in most countries. Table top fusion is also advancing so I'm not so sure things have to be big to be useful. For Tokomaks this probably is a requirement but not neccessarily for other methods.
      Mr. Fusion on your roof: s -selling-solar.html []
    • That just means the installation must be really efficient to compete with existing energy providers... or existing energy providers must become as expensive as this new energy producer. I suspect that in 20 years they will be close to meeting in the middle.

      Depends on operating costs for a Fusion reactor... if the upfront cost can be paid back in another 20 years and operating expenses do not eat up more than half the revenue.. it will do well. If operating costs/upgrades/maintenance/etc. do eat up the major
      • Re:20 years off? (Score:4, Informative)

        by Firethorn ( 177587 ) on Thursday April 26, 2007 @11:27AM (#18885337) Homepage Journal
        That just means the installation must be really efficient to compete with existing energy providers... or existing energy providers must become as expensive as this new energy producer. I suspect that in 20 years they will be close to meeting in the middle.

        From my understanding of the problems, that'd require a HUGE plant. Right now they're talking about building the largest fusion test reactor yet. One telling thing about the design: It's as large as a modern gigawatt nuke/coal plant, yet has absolutely no provisions for making power from the reactions.

        Now, I admit that my figures are estimates, based roughly on the idea that contaiment can be roughly approximated as surface area, while fusion mass is volume based. Thus, square vs. cube.

        Take the test plant*, it's as large as a gigawatt reactor. Since they aren't putting any means to generate electricity in, they're obviously not planning on it producing enough power to even offset the cost of the generating equipment. IE not enough power for it's containment costs.

        Now, lets pretend that we had many issues solved and could merely double the size of it**. 4 times the containment energy cost, 8 times the power produced. If we have a self-sustaining plant, where enough power is generated for it to continue operating with no external power, the doubling would give us 4X the original capacity available to sell.

        Still, even if the first doubling made it self-sufficient, and the second one to produce usefull amounts of power, we're talking about a plant with 16 times the footprint of a gigawatt nuclear plant, half it's power goes to maintaining the reaction systems, and we haven't even gotten to the area need for the steam systems. Call it 20 times the footprint of a gigawatt plant.

        We have a huge way to go on efficiency before it'll be practical. This may help, but I still see fusion plants as a long way away.

        *last I'd heard, they're fighting over which country to build it in.
        **I'm talking about the reaction area size itself. Due to inefficiencies, the rest of the equipment will likely more than double in size.
    • Re: (Score:2, Informative)

      by 91degrees ( 207121 )
      20 years is a lifetime in technology terms. It took less than that for practical nulear fission from the first nuclear reactor. 20 years before sputnik, rocketry was a fe hobbyists causing bangs.

      Look at it this way - pHd students who will be working on that generation are about 10 years old right now.
  • by Etherwalk ( 681268 ) on Thursday April 26, 2007 @10:06AM (#18884019)
    > says that practical fusion power could now be 20 years off.

    Twenty years off what? And are they light years or dog years?
  • by Anonymous Coward
    Cold fuses you!
  • Z-Machine? (Score:5, Funny)

    by Reverend528 ( 585549 ) on Thursday April 26, 2007 @10:12AM (#18884095) Homepage
    The horizon is lost in the glare of morning upon the Great Sea. You shield your eyes to sweep the shore below, where a village lies nestled beside a quiet cove.

    A stunted oak tree shades the inland road.

  • by i_should_be_working ( 720372 ) on Thursday April 26, 2007 @10:15AM (#18884141)
    Well, since every comment here is about that "20 years off" quote, I'll add mine.

    That twenty years (here and decades ago) assumes that governments won't pull funding for fusion research. But they did, and will again. ITER could have been built years ago. It wasn't a lack technology holding it back, it was a lack of money. So don't blame the scientists who give those 20 year estimates, blame your governments.
    • Re: (Score:3, Interesting)

      by Kjella ( 173770 )
      It wasn't a lack technology holding it back, it was a lack of money.

      So all the countries of the world that's economically hogtied to the Middle East doesn't like the idea of vast, cheap energy sources. Right... From what I've understood, getting it started is only a very tiny part of the problem, the biggest problem is "Here's the particles that'll fly out of a fusion reactor. Make electricity out of it". If there really was a clear consensus that it'd be a godsend if we just got it started, it'd have happe
      • by homer_ca ( 144738 ) on Thursday April 26, 2007 @10:52AM (#18884711)

        Here's the particles that'll fly out of a fusion reactor. Make electricity out of it

        They do have a plan for that. A blanket around the reactor containing lithium will both capture heat and breed tritium that's needed for the fusion reaction. One big problem for commercial generation though is the logistical bottleneck of producing enough tritium. Just ITER will use a significant fraction of the world's supply of tritium. The lithium blanket will breed enough tritium for itself and maybe to seed another reactor. uvertures/blk.htm []
        • Also the container will get constantly pummeled with neutrons; this won't mean long-term radioactivity like fission waste, but it does make it harder to keep a plant going for long enough.

          Basically the tokamak has more problems than tritium, though tritium supplies are yet another major problem. The DEMO reactor will be up in ~50 years, and using it to breed enough tritium will take longer, so don't expect tokamak style fusion to make a significant contribution for at least 100 years.
          It must be weird be
        • by LWATCDR ( 28044 ) on Thursday April 26, 2007 @03:04PM (#18889145) Homepage Journal
          You can breed tritium with a fission reactor.
          If you think Plutonium is a weapon proliferation problem you haven't seen nothing yet. Tritium is the key to making really powerful small nuclear weapons. Buy injecting Tritium gas into the core of a nuclear bomb you can boost the yield a lot.
      • by Kohath ( 38547 )
        ...the idea of vast, cheap energy sources...

        If it were more than an "idea" then it would be easier to find funding for it.

        It's interesting that this so-called "cheap energy" source needs 10s of billions of dollars of funding for many, many years to get started.

        I have no doubt that someday, fusion will be a vast, cheap energy source. But right now, it's a hugely expensive energy-sink with no foreseeable return on investment for anyone. Funding for something like that is a gift, not something anyone should
      • by Shakrai ( 717556 )

        So all the countries of the world that's economically hogtied to the Middle East doesn't like the idea of vast, cheap energy sources. Right...

        It's about political willpower. We had the political will to fund Apollo because we needed to beat the Reds. There's no willpower to fund Fusion research as long as fossil fuels remain cheap and available. You also underestimate the power of the oil lobby. Hell, what did Bush do before he was appointed President?

        the biggest problem is "Here's the particles th

      • So all the countries of the world that's economically hogtied to the Middle East doesn't like the idea of vast, cheap energy sources. Right...

        Ahh, naivete. So refreshing.

        The decisions are made by the people with money. The people with the money have a lot more money to make on this oil thing.

        When they can't milk the money out of the fossil fuels any longer, then you'll see the funding for all this stuff appear quickly.

  • by Nuffsaid ( 855987 ) on Thursday April 26, 2007 @10:16AM (#18884165)
    Wouldn't be more honest to say "We have no clue when fusion energy will be practical. Maybe some fundamental research breakthrough will make it doable next year, maybe we need to struggle with the current approach for another thirty years. Please fund research" ?
    • by Firethorn ( 177587 ) on Thursday April 26, 2007 @10:27AM (#18884311) Homepage Journal
      Even if we had a breakthrough and suddenly we had all the equations and knowledge to build practical fusion reactors, fusion power would still be at least a decade away.

      5 years to design it into a power plant, find and obtain a site, necessary permits, etc... Then 5 years to actually build the thing.

      I'll believe that it's twenty years away when we have a working plant sustaining a fusion reaction for testing purposes. IE operating the thing for days/weeks, not seconds/minutes.

      We had [] the first nuclear pile in 1942. The first nuclear reactor to produce electricity came online in 1951. It wasn't until 1957 when the first commercial fission plant came online. 15 years from the first pile until a commercial plant. All signs point towards fusion being bigger and more difficult, so I figure one will take even longer to build than a fission plant.
      • by Latent Heat ( 558884 ) on Thursday April 26, 2007 @11:30AM (#18885399)
        Power reactor fusion has the same problem as Edward Teller's original hydrogen bomb concept.

        The original hydrogen bomb was known as the "Super" before it was called a hydrogen bomb, and the idea is what every wide-eyed geek in elementary school imagines the H-bomb to be -- put an A-bomb next to a vat of deuterium, and the A-bomb blasts the deuterium hot enough to make it fuse.

        As the dudes as Los Alamos started building computers to do numerical models of fluids and radiation and everything, it became apparent that Teller's Super was a dud. The physics of radiation were such that simply sticking a fission bomb next to a pile of heavy hydrogen was simply not going to do anything. What if you sweetened the deuterium with tritium -- then what? As it turned out, you would need gobs of tritium, so the whole thing was a non-starter.

        As it turns out, Stanislaw Ulam came up with the idea of a staged atom bomb -- a small atom bomb would provide the shock to compress a big freepin pile of plutonium to make a big honkin atom bomb, and Teller got ahold of that idea to make the staged H-bomb. The staged H-bomb used to be a very dark secret, but the combination of Richard Rhodes "Dark Sun" and that Progressive Magazine article kind of let out at least the general H-bomb concept. Teller's stamp on the staged bomb was that prompt x-rays from the atom bomb would be the way of getting compression instead of Ulam's original idea of the shock wave, but that the radiation would act first is obvious once anyone with physics knowledge starts working on a staged design, and Teller kind of took all the credit.

        But the actual staged H-bomb not only focuses A-bomb radiation to compress a pile of deuterium, it also compresses a plutonium "spark plug" in the middle to make Ulam's staged A-bomb. The combination of heat and pressure from the radiation compression along with the flood of fast neutrons from the plutonium spark plug manage to fuse the deuterium, which produces its yield mainly in the form of yet more neutrons, which provides fission of a U-238 blanket to provide much of the explosive power of the bomb.

        Fusion is really, really hard, even with the heat and pressure from an atom bomb, and the real H-bomb is a Rube Goldberg set of multiple effects which use fission-driven neutrons to produce fusion neutrons to produce gobs of explosive power from non-critical fission of U-238. Fusion is really, really hard, even for the Sun, because while the Sun is not using deuterium but straight hydrogen, for all of the intense heat and pressure in the interior of the Sun, the reaction rates are really, really low, which is a good thing, because otherwise the Sun wouldn't have lasted 5 billion years to allow us to be here.

        So back to the fusion power reactor. All of the claims of imminent fusion power are based on using lots of tritium for D-T fusion for the same reason that Teller's Classical Super would have needed gobs of tritium and for the same reason that the actual H-bomb that burns D-D needs three stages of fission to get its explosive power. Just as the need for tons of T made Teller's Super a non-starter, the need for tritium means that the current frontier of fusion power is a non-starter. Yes, you breed tritium in the lithium blanket, but you have to compare the breeding doubling time with the half life of tritium and wonder how much seed tritium will you need to get a fusion power economy going and how many decades of breeding tritium will be required to switch the economy over the fusion power before the oil runs out.

        • Very interesting post.

          But I think that it kinda points out where we're at. Fusion is VERY HARD. It gets somewhat easier if you 'spike' the mix with tritium, and larger reactions, while taking more power to initiate, generally release more power as well.

          My point is that I figure that we're going to figure out how to make it workable sooner or later. It's just that version 1 will have a practical plant pushing the size limits. Imagine a plant the size of your average military base. Large enough they buil
        • OK, so let me see if I understand your post:

          Fission is easy, but you've got a finite (and very short) amount of time to actually split atoms, because the whole reaction is busy exploding and you don't have fissionable material in contact with itself for very long. So the trick getting a bigger bang is to figure out ways to get a greater proportion of your fissile material to split.

          If you build a bomb with a chunk of Plutonium inside a shell of deuterium inside the main bomb, you can get the deuterium to fus
        • Re: (Score:3, Interesting)

          by arminw ( 717974 )
          .....Fusion is really, really hard, even with the heat and pressure from an atom bomb.........

          Why spend billions re-creating something on earth which already exists 93 million miles away -- the sun.

          It has been keeping us warm and feeding for millennia. The fossil fuels we now burn are nothing more than stored solar energy. This means that all that carbon we are now releasing must have been on the surface of the earth at one time in order to participate in photosynthesis. For that reason alone, all this glob
      • by afidel ( 530433 )
        I'm an environmentalist but I can guarantee you despite the fact that a fusion plant would be better for the environment that any current power source that the environmental wackos would cause the permitting process to take closer to 10-20 years.
  • ICF, not MCF (Score:5, Informative)

    by generic-nickname596 ( 1035978 ) on Thursday April 26, 2007 @10:28AM (#18884323) Homepage
    It is worth noting (and it is also mentioned in TFA) that this development advances the field of Inertial Confinement Fusion, which is an area that has not traditionally been considered the most likely candidate for commercial fusion power generation. ITER and all other experimental tokamak reactors are of the other variety (magnetic confinement fusion), where a magnetic field is used to keep the plasma in place during the reaction. During ICF, each fusion reaction has a duration short enough that it isn't necessary to hold the plasma back against the forces of gravity. Hence the need to produce a "spark" quickly and efficiently, as many consecutive reactions are necessary to produce any significant amount of power. fusion []
    • Re:ICF, not MCF (Score:5, Interesting)

      by nietsch ( 112711 ) on Thursday April 26, 2007 @10:49AM (#18884677) Homepage Journal
      A few nitpickings: A fusor as invented by Farnsworth et al. (and ongoing navy-funded research by Bussard et al.) does not use magnetism to hold the plasma in place, not all fusion research is done with tokamaks (although most money is spent on them).
      The plasma in a fusion reaction does not fall apart due to gravity. The effects of heat (and thus pressure) is much higher than those of gravity.

      ICF in this form may work, but do they have a method to harvest energy yet? are they close to break even? In theory one could capture emitted alpha particles (they have an energy/speed of several million electron volts, which translates to a very small current of a few million volts), but AFAIK, nobody has done such a feat yet.
      • by Gilmoure ( 18428 )
        So, for now, we're at the just get the fire lit and then we'll figure out what to do with it stage?
    • Re: (Score:2, Insightful)

      by obaloney ( 1038568 )

      During ICF, each fusion reaction has a duration short enough that it isn't necessary to hold the plasma back against the forces of gravity.

      Er, not quite. A fusion plasma must be confined against its own internal pressure, which for ICF is driven sky-high by compression, shock heating, etc., as well as the energy released by fusion reactions. The idea of ICF is simply to get a decent fraction of the target to fuse before the whole thing blows itself apart. In other words, the plasma can be in effect held together—temporarily—by its own inertia.

      Earth's gravity matters not one whit. There is, however, an effective local gravity t

  • See the Z Machine (Score:5, Interesting)

    by Ambitwistor ( 1041236 ) on Thursday April 26, 2007 @10:32AM (#18884393)
    The article lacked a photo of the Z Machine in operation []. Amazing!
  • That's a lot of reps with a lot of power. This is going to end up in missle defence for sure! I doubt funding is going to be an issue here.
    Mr. Fusion on your roof: -selling-solar.html []
  • by J.R. Random ( 801334 ) on Thursday April 26, 2007 @10:37AM (#18884481)
    Practical fusion power is always 20 years from the present. That was true 40 years ago, it is true today, and will be true 40 years from now. This is a little known consequence of general relativity.
  • After actually reading TFA:

    But fired repeatedly, the machine could well be the fusion machine that could form the basis of an electrical generating plant only two decades away.

    I understand this as "this machine could be the basis for a new power plant design within 20 years from now".

    seems like a long wait just for a theoretical power-plant draft...
  • I still think there will be some kind of radiation or gas/plasma that will act to allow quantum tunnelling of some kind.. sort of a fusion catalyst.
  • by BlueParrot ( 965239 ) on Thursday April 26, 2007 @11:04AM (#18884899)
    Contrary to the misconception people keep throwing arround, it wasn't 20 years of 20 years ago. The confusion arises because one was talking about different things. One estimate was when we would reach break-even. That eastimate was for year 2000, and at the time ( 1970) it was 30 years into the future. As it happens, the JET reactor has managed to heat a plasma to the temperatures needed for break-even, but that doesn't mean it is practical as a powerplant. I have a 30 year old book about electricity generation, which estimates the first powerplant for 2050. Furthermore, last time I heard "it was always X years ago", X was 30. Before that X was and had "always" been 50 years ( Tho my Swedish book still says 2050 and was written in the 70ies ). I bet in 2040 we will hear people saying how widescale worldwide deployment of fusion powerplants was "always" 10 more years. When in fact, the estimate of today is that the technology needed to build a practical powerplant ( not necessarily an economically competative one ) is 2027. These "that is what they said back then" quotes usually have no substance in reality. It is just like saying "well they said chernobyl was safe", which of course nobody ever claimed ( in contrast the department of energy stated that no water cooled graphite moderated reactor would be licensed in the US ). However, the claim sounds so damning that people want to believe it. It is the same thing with fusion. The scientists never claimed we would be using fusion plants today. They claimed that IF funding was continued, and IF projects were not cancelled, then we would be able to have a controlled fusion reaction by the year 2000. As it happens we have done better than that. We have managed to initiate fusion reactions that produce more energy than is needed to sustain them. This is however not the same thing as an economically competative powerplant, and it is not the same as ignition ( a fusion plasma that needs no external energy input once it is burning). If you keep changing the goal to be something more difficult, then yes, the goal will always be in the future, that doesn't mean the original estimate was wrong tho. It just mean you were talking about something else.
  • I thought all it could do was play old Infocom text adventures!
  • by brian0918 ( 638904 ) <> on Thursday April 26, 2007 @11:38AM (#18885545)
    I remember seeing a powerpoint lecture given by one of the researchers there, who calculated that to make the Z machine feasible for providing fusion power, they would need to fire one of these off every 0.1 second, so once every 10 seconds is not even close. Plus, the simple fact that there's an enormous explosion going off ten times a second, which destroys the chamber that holds the capsule, makes it seem like there's a definite engineering feat to overcome, otherwise the whole thing is liable to crumble to bits. Right now, they only fire off the Z machine a few hundred times a year... going from that to a few hundred times a minute is a big step.

    I also wouldn't want to live anywhere near there; it feels like a moderately strong earthquake in the area everytime they fire that thing; it seems like the ground beneath and around a rapid-fire facility would quickly weaken and collapse.

    So yes, the Z machine is an excellent source of x-rays, and those x-rays can definitely be used to collapse a fusion capsule, but how applicable is it for fusion power?
    • I know you were actually there, but your concerns seem a bit off. My not-an-engineer take:

      they would need to fire one of these off every 0.1 second, so once every 10 seconds is not even close.

      But for a prototype, a proof of concept? 3 orders of magnitude isn't childs play, but it sure seems like they're moving in the right direction.

      Plus, the simple fact that there's an enormous explosion going off ten times a second, which destroys the chamber that holds the capsule, makes it seem like there's a definite
      • Firing 11,000 times would last a whopping 18 minutes. This thing would have to run continuously. The 11,000 firings were with proper care/repairs/cleanup occurring in between each firing. You wouldn't get that chance when firing 10 times a second.

        You don't seem to know much about geology if you think that simply sticking something on the ground means that it won't move as long as "it's not over a cave". They have to drill down to bedrock to give structures the most stability, but I'm not sure that would
    • by khallow ( 566160 )

      I also wouldn't want to live anywhere near there; it feels like a moderately strong earthquake in the area everytime they fire that thing; it seems like the ground beneath and around a rapid-fire facility would quickly weaken and collapse.

      That probably would not be the case. For example, airplanes and cars are subject to more vibration than the ground would be and are probably structurally a lot less sound. The building is probably built into bedrock. They probably have eliminated all but a trivial amou

    • Re: (Score:2, Interesting)

      by markk ( 35828 )
      Please, this may be to late, but that "enormous explosion" has the energy of about 250 kilowatt hours. That isn't enormous, in fact there are things with similar levels of energy happening all around you. The "explosion chamber" is the size of a thimble of thread.
      If they can get the rate of firing to 1 in 10 seconds that means they have automated it, and don't have to manually rebuild the target every time which would be an advance. None of this means that fusion is just around the corner, but it does mean
      • The chamber is not the size of a thimble; that's just the wire array. I don't remember how large the chamber is that is actually destroyed, but I've seen shrapnel from it that is larger than your hand.
  • by the_olo ( 160789 ) on Thursday April 26, 2007 @12:24PM (#18886403) Homepage

    Interesting, how that relates to Rober Bussard []'s Polywell fusor [], which he claims can be made into a prototype 100 MW plant in 7 years [], provided the needed 200M USD funding []?

    You can also listen to his lecture at Google Tech Talks in 2006 [] to get an idea of what he's up to.

    BTW, you can donate to this fund via Paypal [] and sign the petition [] to renew his funding from the government.

    • Re: (Score:3, Informative)

      by Jerf ( 17166 )
      It appears he's already got some funding []. It's not the $200 million he was hoping for, but based on his Google presentation he ought to be able to do good work with what he's gotten and hopefully prove that the $200 million is justified.

      (I watched that presentation and while it was compelling, I actually think the funding decision made is the correct one. There's a couple of things he really ought to show on a smaller scale before trying the $200 million project; I don't think he's anywhere near exhausted w
  • Yes, this is nice work. Kudos to the researchers. However the biggest problem with building a commercial fusion reactor isn't sustaining the reaction but how to handle all those neutrons. Even if you magically make fusion work, we simply do not know how to capture the heat needed to generate power in any economical way because of the whomping high neutron flux. For the full explanation, see Fusion Power: Will It Ever Come? [] on page 1380 of the March 10th, 10 2006 issue of Science. Since full article
  • it's a steam engine (Score:2, Interesting)

    by Dillenger69 ( 84599 )
    One thing I don't think many people realize is that everything leading up to and including fusion are just heat sources for boilers that power steam turbines.
    Wood, Coal, Fission, Fusion ... all just big old steam engines.
    Has the efficiency of steam turbines progressed much in the last 50 years?
    After fusion would it be better to focus on Steam turbines or the removal of the steam cycle from the power generating equation?
    Thermocouple technology would probably be better in the long run than steam technology mo

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