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Power Science

How To Line a Thermonuclear Reactor 184

Posted by Soulskill
from the very-carefully dept.
sciencehabit writes "One of the biggest question marks hanging over the ITER fusion reactor project — a giant international collaboration currently under construction in France — is over what material to use for coating its interior wall. After all, the reactor has to withstand temperatures of 100,000C and an intense particle bombardment. Researchers have now answered that question by refitting the current world's largest fusion device, the Joint European Torus (JET) near Oxford, U.K., with a lining akin to the one planned for ITER. JET's new 'ITER-like wall,' a combination of tungsten and beryllium, is eroding more slowly (PDF) and retaining less of the fuel than the lining used on earlier fusion reactors, the team reports."
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How To Line a Thermonuclear Reactor

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  • Is composed of the bodies of energy ministers and power-generating companies.

    • by flyneye (84093)

      Or Ducky and Bunny wallpaper. I think an eastern exposure picture window would be nice too.

  • A better first wall (Score:5, Informative)

    by Animats (122034) on Saturday August 18, 2012 @12:51PM (#41037161) Homepage

    This is known as the "first wall" problem in fusion reactors. It's good to hear there's been progress.

    It's discouraging to hear how slow progress is on ITER.

    • Solar (Score:5, Insightful)

      by Bananatree3 (872975) on Saturday August 18, 2012 @12:55PM (#41037189)
      Solar is orders of magnitude simpler in technological complexity, but economic return on solar is just starting to happen. Not because of the technology, simply because population is growing and the cheaper black shit is running out.

      Same thing with Fusion. Technologically, we have enough engineers and scientists in the world to make it a world-scale Apollo type endeavour and get Fusion to market by 2020-2030.... if we wanted to. But honestly, the economy doesn't want to. Not until it runs out of whatever is cheaper.
      • by Anonymous Coward

        You do realize most oil producing countries are on track to produce more oil then any previous year with greater known dril-lable reserves in the ground then at any other point in time???? So it's going to run out really fucking soon... like when we stop finding oil everywhere???? I am not saying burning oil doesn't have problems but the cost of the resource is not going to be one of them for a long time. Oh, I do will have my money where my mouth is am pretty close to shorting oil futures but it wouldn't s

        • Re:Solar (Score:5, Insightful)

          by doublebackslash (702979) <doublebackslash@gmail.com> on Saturday August 18, 2012 @01:17PM (#41037375)

          Bananatree3 likely wasn't being ignorant, but rather stating the situation simply. The economics are driven by... economics. Just because they know where more is and are getting at it faster does not mean that it is the cheap stuff that used to spring out of the ground and soak the plains of Texas and Texans alike. This oil is deeper, dirtier, and more spread out.

          We are really good at getting at oil, because we need it for every piece of modern life, or at least it is the only feasible way to do it. So we get the oil, however we can.

          It would have been more accurate to say, "the CHEAP shit is running out". Other than that I think it is a fine comment.

        • Re:Solar (Score:5, Insightful)

          by Bananatree3 (872975) on Saturday August 18, 2012 @01:21PM (#41037403)
          You're missing the point. I was really pointing at all Fossil Fuels too.

          We'll switch over to alternative fuels long before we run out of Fossil Fuels, simply because they'll be cheaper to produce. A gallon of bio-diesel be cheaper per gallon than petrol diesel at some point, Solar will be cheaper per KWh than burning coal at some point. When that happens, the entire economy will flock over to these alternatives because of price benefits. There will probably be some economic swings as oil/gas/coal producers try to keep competitive, but they're prices will eventually be too high to compete against alternatives.

          It's classic supply and demand. When exponential demand meets a finite resource, prices go up. All the alternative fuels are also finite (only so much KWh of sun can be extracted, for example) but they are also renewable. Fossil fuels don't.

          • BTW, my grammar in my above comment sucks I know lol
          • A gallon of bio-diesel be cheaper per gallon than petrol diesel at some point, Solar will be cheaper per KWh than burning coal at some point.

            That's not such a simple certainty. It's very likely that solar will get cheaper than coal at some point, but the judge is still out on biodiesel.

            There is a feedback loop hidden there, dumped by the EROEI of those sources.

            • Had to google, that and learned something! It appears biodiesel is at the very bottom of the EROEI list: per this Wikipedia chart. [wikipedia.org] How it's produced will have to change dramatically for it to become economically viable to meet current demand. The only emerging technology that seems to have that potential is algae, in some form or another. Of course it will be another decade at least before those technologies can scale to even begin to meet some demand, so it's still unproven at this point.
              • Keep in mind that there is a huge noise on EROEI measures. Basicaly, no two studies find the same values.
                Thus, while those values are a nice overview (enough to get gidelines, like "bio-sources have low EROEI", "hydro can be great" or "few things compete with coal"), don't take them too literaly.

          • by ultranova (717540)

            We'll switch over to alternative fuels long before we run out of Fossil Fuels, simply because they'll be cheaper to produce. A gallon of bio-diesel be cheaper per gallon than petrol diesel at some point, Solar will be cheaper per KWh than burning coal at some point. When that happens, the entire economy will flock over to these alternatives because of price benefits.

            Unfortunately, no. Such a switch requires massive amounts of energy to build the necessary infrastructure. With the economy already being limi

            • We either switch long before we reach the point where it's the physical supply limit that's driving up the price, or our civilization collapses.

              With coal, that point is well past the point where AGW famines and migrations have significantly reduced the population and returned us to the dark ages. So yeah, "make hay while the sun shines" is good advice.

      • THORIUM (Score:4, Insightful)

        by sanman2 (928866) on Saturday August 18, 2012 @01:45PM (#41037595)

        Thorium is better, it's clearly doable, much safer, and it's incredibly abundant.

      • by Panaflex (13191)

        AKAIK - nowhere at any time has ANY scientist shown ANY meaningful energy return on hot fusion research. ITER is the biggest failure of ideas I've ever seen.

        Seriously, that money could be spent on beer and pizza.

        Oil will be gone far sooner than expected - the strategic national stockpile or beer and pizza is not enough to sustain an energy-free economy. Beer and pizza won't just be for Sunday football No, we're going to need all those calories once the economy swings back to human power!

        • by ThePeices (635180)

          Key word here...AFAIK.

          Luckily the world is not limited by what *you* know.

          • by Panaflex (13191)

            Really? Citations? The only similar large-scale experiment I know of was the Oxford JET which only produced 65% of it's input power.

      • Technologically, we have enough engineers and scientists in the world to make it a world-scale Apollo type endeavour and get Fusion to market by 2020-2030

        Bullshit. They've been at it for 30-40 years and still haven't broken Q 1, where Q is the ratio between power inputted and power generated. You need a ratio of 5:1 just to sustain the plasma. 10:1 is needed for power production. The best verifiable results have been Q=.75.

        You can't claim a problem is solvable just by throwing enough money at it.

        • Research on tokamacks started in the 50's. They've been at it for 62 years, and they still can't solve a number of problems, including the fact that the high energy electrons generated tear the machine apart. Nevermind the fact that large parts of the machine become (effectively) permanently radioactive.
          • ...so try and embrace it instead.

            The probability of getting it to work in the near future demands we don't throw everything at it, the same probability combined with the potential payoff demands we keep tinkering and finding solutions to sub-problems or trying completely different designs. Some of those solutions will inevitably be useful in unrelated fields, most won't. We may never get a working fusion reactor but big science (such as the LHC and Fusion) is not just about the questions it was designed
      • Fusion. Technologically, we have enough engineers and scientists in the world to make it a world-scale Apollo type endeavour and get Fusion to market by 2020-2030.... if we wanted to. But honestly, the economy doesn't want to. Not until it runs out of whatever is cheaper.

        If the market does not want it, the states can do it. The market is unable to cope with most of potential economic growth because it is not priced. You noticed Apollo was not drived by the market, did you?

    • by DragonTHC (208439)

      best stuff to use is unobtanium.

  • by AbrasiveCat (999190) on Saturday August 18, 2012 @01:05PM (#41037277)
    With the heath issues around using beryllium, that will be inconvenience. Preparing alloys of W and Be are likely to be expensive for the quantities need too. Melting W takes a lot of heat, fabricating it is hard, if you are machining it with Be you have the heath issue from the finds. Doing it all by PM leads back to the heath issue.Well maybe we can get it fabricated in China or India.
    • I'm told that children just can't resist the sweet taste of beryllium salts. They seem like logical candidates, if we can train them sufficiently in the necessary machining techniques.

    • by zrbyte (1666979)

      It's probably done by robots.

      • Fuck, don't let them hear you call the remote handling equipment 'robots'. I made that mistake, and the scientist showing me around got fair up me for it. It's 'remote handling', not 'robotics', apparently.

        • > It's 'remote handling', not 'robotics', apparently.

          Actually it's waldos. But it certainly isn't robotics.

    • I've seen the facilities they use at CCFE Culham to make and refurbish beryllium components. It's all remotely operated.

    • by fa2k (881632)

      It's not inconcievable to use beryllium. The detectors at LHC have beam pipes made of beryllium. These are the vessels which separate the vacuum in which the particles travel from the detectors. ITER is a scientific institution of similar magnitude.

    • by stevelinton (4044)

      Quantities needed are tiny. It's a surface coating on a few square meters of first wall per gigawatt scale power plant. Not a problem.

  • by catmistake (814204) on Saturday August 18, 2012 @01:07PM (#41037293) Journal

    The Space Shuttles TPS tiles are some amazing material... though even they are only spec'ed to maybe 1500C, but what is facinating about them, to me, is that they don't hold heat. They can be seared to 1200C and seconds later will be cool. So maybe a system that uses this technology combined with an extra liquid-based fast heat-removal system?

    What material can withstand 100,000C ??? How do we test that?

    • by Anonymous Coward

      It's not just the temperature. They need a wall material that does erode impurities in to the plasma. Any impurities will radiate the heat away and cool down the plasma.

    • by Anonymous Coward

      The tiles weren't cool in seconds. They were such amazing insulators that you could pick them up by the corners and not get burned because they wouldn't transfer any significant amount of heat, thus calling them insulators.

    • by mrbester (200927) on Saturday August 18, 2012 @01:46PM (#41037607) Homepage

      What material can withstand 100,000C ???

      The pastry wrapping a McDonalds Apple Pie.

    • by mako1138 (837520) on Saturday August 18, 2012 @02:09PM (#41037807)

      Space-age materials are pretty amazing, but Fusion-age materials are at a whole different level. I think the community hasn't expressed to the public just how daunting the challenges are. Controlling the plasma is one thing, but engineering the plasma-facing components (PFCs) is a whole 'nother kettle of fish.

      The so-called "first wall" is the interior layer of the fusion reactor. It has to stand up to neutron bombardment, but it also has to avoid shedding particles into the plasma. For example high-Z materials such as tungsten, molybdenum, and vanadium are interesting for their neutron tolerance, but if atoms scrape off into the fusion plasma they will radiate like crazy (proportional to Z^2) and drain a lot of energy out of the plasma. That's why they are testing a Be coating (Z=4).

      On the other hand, you have divertors, which sit in direct contact with the plasma and basically hold it in place so it doesn't randomly hit the wall. These have to withstand a high heat load. I admittedly don't know much about divertors so I will stop there.

      There's also the superconducting material in the coils of the tokamak to consider. Of course there's a whole bunch of neutrons flying around. But also but it turns out that a lot of the issues with superconducting magnets are mechanical in nature. The HEP community has figured out how to build SC magnets consistently, but I think the magnets needed for a tokamak are quite different.

      There is supposed to be a International Fusion Material Irradiation Facility, part of the ITER project (and basically a consolation prize to Japan), that will provide intense neutron beams for materials studies. But I am not really sure what the situation/timeline is for that given the funding problems ITER has faced.

    • by elfprince13 (1521333) on Saturday August 18, 2012 @02:15PM (#41037859) Homepage
      The problem isn't the temperature alone, it's also that heavy atoms will pollute the plasma if they come loose at all. The Princeton Plasma Physics Laboratory is working on a liquid-lithium walled reactor to try and handle several of these problems. Check out LTX (Lithium Tokamak Experiment) [pppl.gov].
    • Yeah, carbon fibre composites.

      They were using carbon tiles in JET until fairly recently too. They have some big advantages (tough as hell), but serious disadvantages too (retails fuel and contaminants).

    • > What material can withstand 100,000C ?

      None. Fortunately, nothing has to. That's the temperature of the interior of the plasma, not the temperature of the wall.

  • Interesting (Score:4, Interesting)

    by interval1066 (668936) on Saturday August 18, 2012 @01:13PM (#41037329) Homepage Journal
    Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.
    • by flonker (526111)

      A beaker made out of frozen acid!

    • Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

      I always wondered about that too. I remember being taught about the scientific search for the 'Universal Solvent'. Why didn't these people realized that they were dealing with an impossible subject? As far as I can determine fire is the closest thing to the Universal Solvent.

      • Fire doesn't dissolve anything, it's the energy released from oxidization. As others have said, water is the universal solvent and was when I went to HS in the 70's, I'm sure (like me) you remember what you learnt, but I'm less certain that it matches what we were were taught. ;)
    • Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

      Microgravity and surface tension?

    • This problem also adds the additional problem:

      "What do you use to hold an acid that can eat anything? And said container when dissolved must not neutralize the acid or reduce its potency."

      Tough enough to build a container. Doubly difficult to find something tough enough that won't contaminate the solvent.

  • by PPH (736903) on Saturday August 18, 2012 @01:14PM (#41037339)

    ... insurgents in West Africa take control of tungsten and beryllium mines pillaging and burning villages in their path. It is expected that their profits related to the fusion reactor market will sustain inter-tribal conflicts for generations to come.

    If this [youtube.com] is the alternative, I say we start developing rare earth mining in this country ASAP.

  • by Joe_Dragon (2206452) on Saturday August 18, 2012 @01:17PM (#41037369)

    how long will it last with homer at the controls?

  • by elfprince13 (1521333) on Saturday August 18, 2012 @02:16PM (#41037869) Homepage
    I've been working at PPPL this summer, and that's the latest idea [pppl.gov]
  • I find the weirdest shit every time I go there.

  • Twenty years ago I was a program officer at the Office of Fusion Energy, US Department of Energy. The ITER planning had started. My take -- there is no way on Earth that a tokamak can be cost competitive. Even if it works, even if the first wall problem is solved as may be indicated above, the engineering costs are so prohibitive as to price the whole concept out of consideration.

    I earlier worked on Trisops [wikipedia.org], a simpler fusion concept that might be economically feasible, but I even doubt that. In the official fusion community, which is fixated on the the tokamak, it suffered from the NIH ( Not Invented Here ) syndrome and was defunded.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      I earlier worked on Trisops, a simpler fusion concept that might be economically feasible, but I even doubt that. In the official fusion community, which is fixated on the the tokamak, it suffered from the NIH ( Not Invented Here ) syndrome and was defunded.

      Don't forget Dr. Bussard's Polywell [wikipedia.org] concept.

      It's under a publishing blackout because it's a project currently being funded by the Navy, but the fact that it's still being funded is encouraging.

    • by Goldsmith (561202)

      So why are we still funding fusion research at a billion dollar level? Why can't program officers get the message up the chain that funding should go elsewhere? There are similar fields ticking along with $100M/year funding.

      I'm just getting started reviewing programs, but I can't wrap my head around this concept that wasting money is what you have to do as part of government scientific oversight. There are way too many good projects that go unfunded to spend money on things serious scientists agree will

      • by InterGuru (50986)

        One aspect is that we are part of an international consortium, and to pull back would initiate an diplomatic scuffle. In a more rational world we would't be building this.

        To put things into perspective it is not more money than we use to bail out one sleazy banker so he can get his bonus, or run a few days of a stupid war.

    • by careysub (976506)

      Twenty years ago I was a program officer at the Office of Fusion Energy, US Department of Energy. The ITER planning had started. My take -- there is no way on Earth that a tokamak can be cost competitive. Even if it works, even if the first wall problem is solved as may be indicated above, the engineering costs are so prohibitive as to price the whole concept out of consideration.

      ...

      Right you are, and the economics are even worse than what you suggest. Consider the breeding blanket problem. Putting aside the immense difficulty of creating a blanket that meets its stringent neutron economy and heat transfer issues (it may be as hard as the break-even problem, and may not even be possible), the capital cost for such a blanket - just price din term of the raw materials - makes fusion power more expensive than conventional nuclear power, and nuclear power's high capital cost is already the

  • This sounds like it would be worth a try:
    http://www.telegraph.co.uk/technology/5158972/Starlite-the-nuclear-blast-defying-plastic-that-could-change-the-world.html [telegraph.co.uk]
    The inventor sounds a little eccentric, but if it does the job I'm sure someone can deal with that
    • by PPH (736903)
      I think this is what they make those disposable grocery bags out of.
    • The main problem is that most extreme heat resistant materials contaminate the plasma. The impacts are so high energy that they boil some of the material (even Starlite doesn't promise 100,000 K). That boiled away lining material messes with the plasma. Thus one of the demands of the lining is that contaminations of it should not mess with the reaction.
      Beside that, if that article is true then that is an awesome material. To bad the stuff hasn't gotten in common use due to massive distrust (on all sides).
  • Where's the horse?
  • Nothing melts it.
  • Incredible! Instead of rubbing woad into their belly buttons and praying to Jesus, these filthy scientists have gone away and performed EXPERIMENTS - real, disgusting physical EXPERIMENTS, I tell you !!! to try to evaluate a complicated technical question.

    We must band together to stop this erosion of the power of prayer to the All-Mighty YHWH. If these disgusting, sub-religious people and their filthy, filthy heresies were to gain a foothold, then you never know but the altars of Zeus will one day not be p

One man's "magic" is another man's engineering. "Supernatural" is a null word. -- Robert Heinlein

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