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Japan's JT-60 Tokamak Sets New Plasma Record

Posted by Zonk on Sat May 13, 2006 02:39 AM
from the road-to-the-fusion-reactor dept.
Power Science
Dipster writes "The Japan Atomic Energy Agency has announced that its JT-60 Tokamak has almost doubled the previous record for sustained plasma production, which is now sits at 28.6 seconds. It is believed that once 400 seconds can be achieved, a sustained nuclear fusion reaction will be possible. While 28.6 seconds is a long way from 400, it raises hopes for what will be possible from the ITER reactor, expected to be finished in 2016."
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  • Almost there... still (Score:5, Funny)

    by DieByWire (744043) on Saturday May 13 2006, @02:47AM (#15323885)
    While 28.6 seconds is a long way from 400...

    Let's see, 400 seconds - 28.6 seconds .... works out to about 50 years. Still.

    • "Let's see, 400 seconds - 28.6 seconds .... works out to about 50 years." Wow, I've seen some bad math before but jeez... 400 seconds - 28.6 seconds works out to 371.4 seconds
    • With only these two data points (16.5 sec in 2004 and 28.6 in 2006) we can get 400+ seconds by the year 2018. While two years behind the 2016 date, is probably ahead of schedule if I know anything about building schedules.

      Movies have let me down. I was supposed to be flying around Mars on my Mr. Fusion powered space car 15 years ago.

      • Movies have let me down. I was supposed to be flying around Mars on my Mr. Fusion powered space car 15 years ago.

        I was supposed to have a time-traveling DeLorean by now.

        Did anybody else read "400 seconds" as "88 MPH?"

    • Re:Almost there... still (Score:4, Interesting)

      by proverbialcow (177020) on Saturday May 13 2006, @03:17AM (#15323933) Journal
      Let's see, 400 seconds - 28.6 seconds .... works out to about 50 years.

      If you assume that they'll only be able to increase the time linearly, then yes, it's about fifty years.

      If you assume that they'll be able to keep refining the technology and keep doubling the time every two years, then we're only looking at 7.6118259 [2*log(400/28.6)/log(2)] years.

      It's probably somewhere in between that, though I'd guess toward the lower end. (As they keep getting closer, more attention will be given to the problem, etc.)
          • Does anyone remember a short science fiction story that basically had that as a premise? I can't remember what it was called or who it was by, but the idea was that a civilization built a generator that provided wireless power distribution throughout not only all three dimensions, but forward into the fourth as well. So basically as soon as it was turned on, you'd have power for the rest of eternity, even if you shut it down.

            The story used this as a device to show how easily people "forget the development,"
    • Let's see, 400 seconds - 28.6 seconds .... works out to about 50 years. Still.

      When Goddard demonstrated his first rockets, it was widely reported that he missed the moon by only 250,000 miles.
  • until fusion power can be put into production? I know a lot of advances have been made in the last few years, small scale fusion using pyroelectric crystals and such, but really how far are we from the goal? Can anyone in the know comment?

    I know its pretty unreasonable to ask "when is technology x coming out," but a rough order of magnitude (are we talking 10 years? 100?) has got to be doable.

    Also, if we do get large scale fusion, is it really going to be cleaner and safer than modern fission plants?
    • I know its pretty unreasonable to ask "when is technology x coming out," but a rough order of magnitude (are we talking 10 years? 100?) has got to be doable.

      It's about fifteen years away.

      Five years ago, it was about ten years away. That's progress for you.
      • It's about fifteen years away.

        Five years ago, it was about ten years away. That's progress for you.

        Perhaps, sometimes, it's best that we're ignorant to how hard it's going to be... Otherwise, we might not start at all.

    • Re:How long (Score:5, Informative)

      by RsG (809189) on Saturday May 13 2006, @03:11AM (#15323925)
      "Also, if we do get large scale fusion, is it really going to be cleaner and safer than modern fission plants?"

      No meltdown risk...

      No long-lived waste products...

      No dangerous fuels...

      Likely no immediate danger of weapon proliferation...

      And you have to ask if it's safer?

      Just so we're clear, fission power is reasonably safe already (provided the reactors are well designed and maintained, and provided that the waste is reproccessed). All of the dangers of a fission plant are outlined above, and they're not that bad when compared with the alternatives. Fusion has none of those dangers; the nuclear reaction ceases if the reactor vessel loses confinement, the major waste product is helium-4 (which is commercially useful and chemically inert), reactor irradiation is minimal, and can be limited further by careful choice of building materials, the fuels are safe to handle, and there's no way to make a bomb out of the reactor technology that we know of yet.

      That's not to say there are absolutly no problems. Even with careful material selection, the reactor vessel will become slighly radioactive over it's lifetime. But safer and cleaner than fission? Yes, and by an order of magnitude at that.
      • Normal fission doesn't have to have long lived products either if you use a integral fast reactor http://en.wikipedia.org/wiki/Integral_Fast_Reactor [wikipedia.org] Mark
        • The waste doesn't have to be especially long lived no matter what method of recycling you use. It's only when you don't recycle the waste that you run into problems.

          However, consider what we're comparing to. The waste product of a fusion reaction (using deuterium and tritium fuel) is helium-4, which is safe and useful. The only radioactivity is through neutron activation, which isn't precisely "waste", and isn't even close to a fission plant.

          Long term is relative. From a human perspective, if we have to

      • Re:How long (Score:5, Informative)

        by Tim C (15259) on Saturday May 13 2006, @04:10AM (#15324003)
        reactor irradiation is minimal

        Now I freely admit that things may have changed in the 7 or so years since I quit my Phd in plasma physics, but back then that simply wasn't true. One of the major byrpoducts of a fusion reaction is (was) a pretty steady flux of neutrons. Being neutral, the only way to contain it is to absorb it. This shielding will become radioactive, and will need to be replaced periodically. It is inevitable that eventually, the entire reactor will have been damaged to the point of having to be replaced; it will all also be radioactive.

        Now it's true that the half-life of the irradiated components is much, much shorter than that of the waste products of fission, and (imnho) fusion is absolutely the way to go long-term for nuclear power. However, I really don't think it's true to say "reactor irradiation is minimal".

        Like I said though, it's been some time since I last really looked at this, so it's possible that progress has been made. It's also not impossible that I'm mis-remembering things (or simply misinterpreting your meaning), of course.

        • Re:How long (Score:5, Informative)

          by RsG (809189) on Saturday May 13 2006, @04:53AM (#15324045)
          When comparing to a fission based reactor, perhaps my use of the word "minimal" was a tad skewed.

          Remember that the object of comparison here has the same issue with neutron irradiation (ie, even ignoring waste products, a fission reactor core will become irradiated over time, as will the coolant in the heat exchangers). In addition to the neutron problem, which applies to both fission/fusion, you've also got to consider direct radioactive contamination from the fuel/waste. At least with a fusion reactor we can eliminate (or reduce) the risk of elements like strontium-90, since we get the option of choosing what radioactives we want left over at the end of the plant's life when we build it.

          But I cede the point that, objectively, the degree of radioactivity in the core of a decomisioned plant would not be "minimal" by human standards.
            • But compared to a fission or coal burning plant? I don't see the radiative waste problem being that onerous.
    • Well, if you want to take the article at face value, probably somewhere in the 2020's. I'd guess 2025-2029 at this rate. Perhaps faster if we really have or are about to hit peak oil as some have claimed.

    • Re:How long (Score:5, Informative)

      by Eric Smith (4379) * <eric@brouhah a . com> on Saturday May 13 2006, @03:22AM (#15323938) Homepage Journal
      How long until fusion power can be put into production?
      About 50 years.

      And I'm not just being flippant, though the answer has been 50 years for the last 30 years or more.

      ITER isn't going to be operational until 2016 at the earliest, and it's an experimental reactor not expected to be a net energy producer. Based on operational experience with ITER and IFMIF (for which construction has not even started), another experimental reactor will be designed and constructed with the goal of net energy production. Perhaps that might be operational by 2035. And if it works well enough, it's *remotely* possible that a commercial reactor could be designed and constructed, and be operational by 2055.

      When all is said and done, fusion recactors are expected to produce *slightly* less expensive electricity than fission.

      The big win with fusion will require a major theoretical breakthrough rather than simply carrying the current plans to their logical conclusion.

      Also, if we do get large scale fusion, is it really going to be cleaner and safer than modern fission plants?
      In general it's reasonable to expect that they'll be cleaner and safer. There is no possibility of a runaway chain reaction; the reactor only contains enough fuel at any given time to operate for a fraction of a second, vs. months or years for a fission reactor. If the fusion reaction containment fails, the reaction quickly stops, without serious damage to the reactor and without any abnormal leakage of radioactive material. A fusion reactor can't "melt down".

      A fusion reactor will produce a greater quantity of radioactive waste (crumbling radioactive shielding and structural materials after years of exposure to high neutron flux), but fortunately the waste will have a very short half-life so it won't be dangerous for too many decades, and will thus be easier to store. No need to worry about safety over geological time scales, or about whether our descendents will be able to read warning signs printed in 21st century languages.

      • If the fusion reaction containment fails, the reaction quickly stops, without serious damage to the reactor and without any abnormal leakage of radioactive material. A fusion reactor can't "melt down".

        Unfortunately, like most reactors, it will collapse into a pile of rubble after exactly 50 years. Which is why I prefer to use hydroelectric power...

        Oh, wait, we were talking about Sim City, right?

        -:sigma.SB

    • "[How long] until fusion power can be put into production? I know a lot of advances have been made in the last few years, small scale fusion using pyroelectric crystals and such, but really how far are we from the goal? Can anyone in the know comment?"

      I know its pretty unreasonable to ask "when is technology x coming out," but a rough order of magnitude (are we talking 10 years? 100?) has got to be doable."

      Depends on how much money gets thrown at it. If ITER shows promise, and there's really no technica

    • Re:How long (Score:5, Informative)

      by deglr6328 (150198) on Saturday May 13 2006, @04:55AM (#15324049)
      It it worth noting that the progress made in fusion research has been HUGE throughout the past 3-4 decades [jaeri.go.jp] and while the next step is more difficult than the last we aew still making steady progress. JT-60 HAS attained a confinement quality in the deuterium-deuterium shots it has taken which are VERY good, so good that if they were done with deuterium-tritium mix they would firmly place JT-60 in the breakeven parameter space very near the ignition regime (they have not "gone DT" due to pain in the ass handling issues with the radioactive tritium). There is also always hope for a shocking surprise breakthrough too (but don't hold your breath). For example, 10 or so years ago, it was though there was no way you could get around having to build immensely expensive [llnl.gov] multi-hundred beam multi-MEGAjoule laser systems in order to make inertial confinement fusion [wikipedia.org] work. Then along comes a cute little trick called Chirped pulse amplification and suddenly you can start talking about petawatt lasers being used to reduce the overall cost of the machine by 10 fold (fast ignition fusion schemes [oemagazine.com]! That's why science is so great, there is always hope something better is just around the corner waiting to be discovered.
      • Also, Tore Supra has achieved discharge durations in excess of 200 seconds since 2002 and has more recently had shots in excess of 360 seconds (6 minutes). Of course Tore Supra has a significant advantage over most other tokamaks in that it has superconducting toroidal field coils, giving it a steady state toroidal magnetic field. My experience in working with these machines is that on most of them the toroidal magnetic fields seriously handicap their performance due to the massive power requirements of g
    • It isn't a question of how long. It is more a question of dollars.

      It is often said that 20 years ago, the physics community estimated that they could have reactors working in 20 years. People usually ignore that this was only the first half of the estimate -- the other half was the level of funding needed to achieve the result. Needless to say, they received a small (and still shrinking) fraction of the funding they said was necessary, and the result is unsurprising.

      Everyone laments the expense of large sca

  • fusion (Score:2, Interesting)

    by ebooborg (935299)
    as someone who worked in the energy generating business i hope fusion comes sooner rather than later!

    the price of oil and gas are going thru the roof, and these two fuels are what keeping the base load plants running here in ireland (and most of the rest of the world with notable exception of france)

    theres alot of buzz around wind power nowadays but alot of people dont realise that with average 20% availability (compared to 80-90% of base plants) wind power
    just doesnt cut it, and u need to have for
    • The greens (and other similar political groups) scaremonger against nuclear because it is (according to them), the greater of all the available evils.

      If you want nuclear to succeed, you need to find a greater evil, for example:
      "
      Scientists have released details of a discovery last month that when a tiny adorable kitten is poked with something pointy and sharp, an incredible amount of energy is released, many many orders of magnitude more energy than the kitten would consume in food during its entire life.

      The
      • Suddenly nuclear doesn't seem like such a bad option :)

        Pfft. You're talking to geeks here.

        If there was a device that minced 3 kittens an hour and gave you an extra 5 fps in quake, we'd be all over it.
    • Have you ever tried to count the neutrons that come off a fusion reaction? If you do you will see that there are so many that the _best_ use of fusion once we get it will be to operate as a breader for U239->Pu239/Pu240 production or th232->U233. These are viable fuel cycles.

      The short of it is that fusion is rather dirty - just as bad if not worse than fission and the reason is because of all of those neutrons that are released.

      Forget about OIL & GAS dropping in price for any length of time.

      Saud
        • Call me ignorant, but what's the Irish objection to nuclear power?

          I don't get it. You'd think the Greens would be all over nuclear (fission) power. It's clean, and the only problems with it are ones that can be solved: meltdown and the production of waste are both manageable, and with a little effort and ingenuity. The risk of meltdown has basically been solved by new reactor designs, as I understand it.

          The problems in coal and oil power are not solvable, namely the CO2 emission and the fact that we're goin

  • Only 10 years till FUSION! (Score:4, Funny)

    by ookabooka (731013) on Saturday May 13 2006, @03:15AM (#15323929)
    "...it raises hopes for what will be possible from the ITER reactor, expected to be finished in 2016."

    Look at that, it'll be completed in exactly 10 years. Finally, this time 10 years means 10 years.
    • But, progress is being made, maybe the rate of progress is a lot slower than anticipated. But it's clear physicists are getting closer and closer. The public needs to be patient and not cut off funding. Just because the 50 year prediction was wrong doesnt mean that this is a fundamentally impossible acheivement, as we can see, progress is being made.

      My main concern is the current environmentalist movement which doesnt want humans have a decent quality of life with cheap access to energy. They are stuck on
      • Modern commercially available solar panels, depending on type, pay off their production energy in 2-5 years, and last 20-30 years.

        Modern windmills turn at a whopping 18rpm, slow enough for birds to clearly see and avoid. Their appearance is subjective, but I kinda like 'em. Their production may not be pollution-free (after all, NOTHING is) but in terms of power produced per unit of pollution, they are the standout winner across the board right now.

        Nuclear power is a fantastic option that needs wider deplo

  • Subject? (Score:5, Funny)

    by zaguar (881743) on Saturday May 13 2006, @03:35AM (#15323956)
    Was I the only one who thought that it was for a 60-inch plasma screen?

  • The reason it's always 30 years off (Score:2, Interesting)

    by Anonymous Coward
    Fusion research is one of the only promising research fields whose funding has decreased substantially over the years. In 1970 it was predicted that ITER would be online in 1995, with a demo commercial reactor in 2005. Given that funding was cut once the oil crisis was over, is it reasonable to expect all deadlines to remain the same? In any case, now that construction has started on the ITER site, we are definitively 10 years from an net positive energy balance plasma, following ITER's research, speculated

  • fusion (Score:2, Informative)

    by wwmedia (950346)
    to all you wanting to get more info

    ITER is designed to produce approximately 500 MW (500,000,000 watts) of fusion power sustained for up to 500 seconds (compared to JET's peak of 16 MW for less than a second). It is a significant amount of power for a fusion research project; a future fusion power plant would generate about 3000-4000 MW of thermal power. Although ITER will produce net power in the form of heat, the generated heat will not be used to generate any electricity.

    http://en.wikipedia.org/w [wikipedia.org]

  • WOW! (Score:5, Interesting)

    by maddogdelta (558240) on Saturday May 13 2006, @05:19AM (#15324080)
    As a bachelor degree student in physics in the 70's and early 80's, fusion research was on of the 'hot' topics. The tokamak was the predominant fusion plant, but other fusion reactors were being investigated. In those days we measured sustained reaction times in milliseconds. Obviously I haven't been keeping up, 'cuz 28 seconds sounds like a lifetime to me now.
  • Forgive me if I'm missing something completely obvious here, but why is progress in fusion research still progressing so slowly? Sources generally cite estimates in the 2050-2060 range for when we'll be actually using fusion power.

    The actual research itself is relatively unpredictable, I understand that. But when I read that completion of the ITER (the way I see it a relatively straightforward job, I assume the blueprints are already completed) is still 10 years away, I wonder how much time could be shaved off that estimate, as well as the ~2050 estimate, if (a lot) more money were put into fusion research.

    If nuclear fusion has the potential to provide a clean, efficient, lasting energy source, and thereby eventually solve the energy crises, it would seem to me that investing a far larger amount of money than is being put into it today would be a very good investment if that could mean nuclear fusion can be used a few years earlier. I think ITER's cost is estimated at about EUR 10 billion, which is a lot of money, but in the grand scheme of things (I think the world GDP is somewhere around 50 trillion) it's tiny. And seeing the large potential for creating armed conflict there is in energy shortages even these days, I'd say getting fusion sooner rather than later may very well be a real matter of life and death.

    However, when I hear discussions on the energy crises, the efficiency of solar/wind/water power, whether more nuclear fission reactors should be built, fusion isn't even mentioned, let alone considered by politicians for larger investments. Is it simply because it's so far away, and that for the most of us, only our descendants would benefit from those investments?

    Once again this is a serious question, I'm no expert in any of this so I honestly don't know.

    • Some humour to start: " Sources generally cite estimates in the 2050-2060 range for when we'll be actually using fusion power.", SimCity 2000 is NOT a source!

      I think the slow investment in fusion, bio-diesel, eco-friendly widget X, or sciencey cool widget Z is because it is just that, INVESTMENT. Investing, even from the government, is a matter of getting something back from that investment in a reasonable time.

      I am inclined to agree with your guesstimate of 2050 for viable energy from fusion. So we would h

  • Why is Tore Supra ignored here ? (Score:3, Informative)

    by boule75 (649166) on Saturday May 13 2006, @07:09AM (#15324233) Homepage
    I always wonder why Tore Supra is ignored here or in the US Wikipedia.

    As far as I can read, it seems rather impressive. Their record for plama duration is... 390s ! More information on the fusion-dedicated French CEA (Commissariat à l'Energie Atomique) site [www-fusion...que.cea.fr] (in English).

    But the question is honest: what have achieved the Japanese? Is their plasma self-sustaining? Have they reached break-even point and maintained it during the whole 28.6 seconds?

    Anyway, just give a look to the CEA site: from pictures to videos, plenty to discover there.

  • An Easier Way (Score:2, Funny)

    by Anonymous Coward

    We could have nuclear fusion power now, we could have had it decades ago, were it not for political concerns. Consider this:

    1. Build a huge spherical chamber (possibly a mile in diameter)
    2. Cover the inside with energy collectors
    3. Drop a nuclear fusion bomb from the top, timed to detonate when it reaches the center
    4. Repeat previous step every five seconds.

    Such a setup should generate more fusion power than we'll ever need.

    But of course you'd have to manufacture fusion bombs at a rate of one every five seco

    • There are lots of reasons this wouldn't work. Off the top of my head:
      - Insufficient technology to build a spherical structure of that size.
      - Even at miles in size, the detonation of a hydrogen bomb would yield huge overpressure waves, and arch construction is good at being compressed inwards, not outwards.
      - Hydrogen bombs requires a fission reaction to detonate - it would be more efficient to fission the fissionables in breeder reactors. - What, exactly, are "energy collectors?"

      • Actually... (Score:3, Interesting)

        by cr0sh (43134)
        Actually, I think we certainly do have the technology - if you modify the parameters a bit:

        First off, the spherical chamber: Do what Operation Plowshare did, use a nuke to build the chamber by detonating it underground. I bet that if you mined ventilation shafts at the near "edge" of the explosion, you could vent off the overpressure. The heat from the explosion would sinter the rock together. All that would be left would be to send in some remote-controlled mining equipment to "smooth" it out. You aren't t

  • Will the be able to keep it open^H^H^H^H powered on for more than 38 minutes?

  • My prediction (Score:3, Insightful)

    by ceeam (39911) on Saturday May 13 2006, @10:05AM (#15324637)
    I predict that we will have fusion power not before oil reserves are exhausted - too much money/politics/everything involved. Can't be allowed. If we have fusion power production tomorrow - what would all those arabs do? Huh?

  • For God's sake!! (Score:5, Informative)

    by styryx (952942) on Saturday May 13 2006, @05:12PM (#15326646)
    Everytime I read any Fusion based posts it really allows me to see how ignorant a LOT of people are. Some seem pretty close, but get caught out as being bulls-hitters somewhere in their post

    K, I am doing a PhD in Fusion in one of the best fusion plasma groups in the world. I would be happy to answer any questions.

    Not having a go at any random posts, but just a few mistakes I didn't see get checked. 1. Yes Fusion is safe, very safe, super safe. Safe!! You can ask me why, but no-one ever seems to pay attention, or even understand.

    2. Fusion weapons have been around since at least the 1960's! Hydrogen bombs. Kinda like 50 years too late to be scared about that one.

    3. Would you like to know why fusion isn't here yet? It's very difficult! It's not an oil conspiracy!! The people in fusion are academics and believe me when I say they don't generally give a crap about money. They are smart people concerned with the environment.

    4. Why is it difficult? You can't switch JET or MAST on for too long because of Ohmic heating. It basically implies that super conducting (very $$$!) coils are needed to get around this problem. ITER will be one of the first reactors to have all superconducting coils.

    6. Anything else? Yes, actually. We are literally making it up as we go along. How many people know exactly what a plasma is? I mean what defines it? It's Debeye length? Collisionless? Quasi-neutrality? What do any of these terms mean? If you don't know you probably aren't qualified to talk on fusion. Plasma physics is relatively to the rest of science an incredibly new and young field and it is extremely varied.

    There's lots and lots going on in fusion. I apologise for the lack of links but i'm typing quickly and don't have time. Suffice to say, everyone in the fusion community is very enthusiastic about it. It is getting more and more (international) money all the time. The Chinese and Japanese are involved, not to mention India and the most of the West.

    On an interesting side note. The thing that mainly held fusion back was
    can you guess?
    AMERICA!! Constantly pulling in and out of the project. However, now that the Indians are involved the funding is about 110% of what is required. So if the yanks pull out again then they will fall behind because no-one else cares anymore and we'll have enough money to, and we will, continue.

    • Re:fusion (Score:5, Insightful)

      by Guppy06 (410832) on Saturday May 13 2006, @08:08AM (#15324315) Journal
      "There is no perpetual motion energy source."

      Perhaps, but when your fuel source is the most abundant substance in the universe, there's "close enough for engineering purposes."

      "Where is the balancing "bad" for fusion energy?"

      You seem to be confusing thermodynamics with kharma.

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