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China Claims Successful Fusion Power Test 247

Posted by kdawson from the bang-'em-together-hard dept.
SeaDour writes, "China claims to have carried out a successful test of its experimental thermonuclear fusion reactor. But what exactly made this test 'successful' is not clear. From the article: 'Xinhua cited the scientists as saying that deuterium and tritium atoms had been fused together at a temperature of 100 million degrees Celsius for nearly three seconds. The report did not specify whether the device... had succeeded at producing more energy than it consumed, the main obstacle to making fusion commercially viable.'" China is a participant in the 10-nation ITER project to build a fusion reactor in the south of France by 2015. The article quotes the research head of ITER as saying, "It was important for China to show that it is part of the club. Here are English language versions of the Chinese news release: announcement, background.
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China Claims Successful Fusion Power Test More

China Claims Successful Fusion Power Test

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  • China's definition of success (Score:5, Funny)

    by davidwr ( 791652 ) on Thursday September 28, 2006 @03:11PM (#16234727) Homepage Journal
    "We're pleased to announce we are still here to report the results."

  • Oh... (Score:4, Funny)

    by ackthpt ( 218170 ) * on Thursday September 28, 2006 @03:12PM (#16234729) Homepage Journal

    100 million degrees Celsius for nearly three seconds.

    I think someone needs a CoolerMaster for that one!

    bad news, the coolermaster consumed all the net energy

    • Re:Oh... (Score:5, Informative)

      by RsG ( 809189 ) on Thursday September 28, 2006 @03:17PM (#16234853)
      Nah, you want it to get as hot as possible. Higher temperature leads to more reactions in the fuel, which in turn leads to greater effeciency. Part of the problem is getting the fuel that hot in the first place, and keeping it together long enough to fuse.

      Side note: while 100 million degrees sounds awfully hot, we're talking about a tiny amount of fuel here. The usual figure quoted for a hypothetical commercial reactor is about two grams of fuel in the core at any given time. The reactor itself doesn't get anywhere near that hot, even in the event of a full loss of containment.
  • Will be tied to their ability to get away from fossil fuels and develop alternative sources. They, not the United States will be the leader in developing the "big thing" that moves us beyond our oil based economy.

  • I'm pretty sure it didn't hit Q=1 (Score:4, Informative)

    by spike hay ( 534165 ) <{blu_ice} {at} {violate.me.uk}> on Thursday September 28, 2006 @03:18PM (#16234867) Homepage
    It was successful in that it fused deuterium and tritium. Of course, the break even point doesn't matter. To be economical, the reactor realistically has to hit ignition, which only the ITER could hope to do.
    • It was successful in that it fused deuterium and tritium. Of course, the break even point doesn't matter. To be economical, the reactor realistically has to hit ignition, which only the ITER could hope to do.
      Exactly. It's an experimental reactor, not an experimental power plant. It was successful in reacting, not necessarily in generating net power.

    • Re: (Score:3, Informative)

      by kidtexas ( 525194 )
      Actually, it was successful in getting plasma, usually called "first plasma" in the field. I had heard it was 200kA for 1.2 seconds. I'm would be shocked if they actually were using tritium in the system at this early stage, but I could be wrong. I'm betting that was the result of the scientist media interface.

      ITER, which is designed for a Q of 5-10 I think and most definitely for DT plasmas, is supposed to reach first plasma in 2016. I think the first DT plasmas for ITER are scheduled for 2019. The o
      • I concur about the tritium thing. There's NO WAY they've gone DT yet, that would be nuts. Am I correct in thinking that HT-7U (also (was) in china) is the only other superconducting tokamak ever built? That can't be right. KSTAR the Korean superconducting reactor is still in the planing stages and I am unaware of any others (perhaps with the exception of the hightemp superconductor in the levitated dipole experiment but that's not a tokamak really). It seems so obvious, if you want high B fields....why are
      • According to various chinese news media, the significant of EAST experimental reactor is two fold: first it is all super conducting, second, it adopts a toroid with a non-circular cross section. So far, EAST's reactor design is most similar to ITER. Yes, its role is kind of supportive and serves as training ground/ testbed for ITER.
    • To be economical, the reactor realistically has to hit ignition

      Ignition isn't Q=1. Breakeven is Q=1. To be economical, a D-T reactor's going to have to hit Q ~= 20; that is, 20 times as much energy coming out as you're putting in.

      Ignition is what you get when the reaction sustains itself with no input energy at all; Q = infinity, basically.
      • Ignition isn't Q=1. Breakeven is Q=1. To be economical, a D-T reactor's going to have to hit Q ~= 20; that is, 20 times as much energy coming out as you're putting in.

        Ignition is what you get when the reaction sustains itself with no input energy at all; Q = infinity, basically.

        That's basically what I was getting at.

  • Net gain not the obstacle! (Score:5, Informative)

    by The_Wilschon ( 782534 ) on Thursday September 28, 2006 @03:19PM (#16234889) Homepage
    Achieving a net energy gain is not the main obstacle to making fusion commercially viable. That has been done quite successfully. There is no problem passing break-even. It is ignition we are trying to achieve now. That is, a fusion reaction which produces enough heat to cause more fusion, provided enough fuel. If you're going to write an article about fusion, at least know something about the state of the field. Journalists should all be required to read the relevant wikipedia [wikipedia.org] articles before publishing something about science.
    • although complex, if there IS a net gain, couldn't that be used to keep the reaction going, even without ignition?
      • although complex, if there IS a net gain, couldn't that be used to keep the reaction going, even without ignition?

        That's pretty much the definition of ignition. It turns out you need a lot of net energy to keep everything at the proper temperature. So Q=1 is not nearly sufficient.
        • net gain: more energy comes out than went in -> with a net gain, you could restart the process from scratch, repeatedly and get more energy each time, even without a self-renewing reaction.

          • Re: (Score:2)

            by RsG ( 809189 )
            I'm pretty sure the problem with that is commercial viability, not any physical limitation. Remember that the reaction only needs to excede it's energy input by a tiny amount in order to break even, so it's not a simple jump from a net energy positive reator to a power generator.

            I'm pretty sure that if we improved the tech to the point where producing useful levels of energy was possible, then we'd have already passed the threshold for ignition; ie making the reaction self-renewing is an intermediate step
      • I think part of the problem is even though there is a net gain the energy being released needs to be contained within the fuel instead of escaping.

    • Re:Net gain not the obstacle! (Score:5, Funny)

      by Howserx ( 955320 ) on Thursday September 28, 2006 @03:39PM (#16235257)
      Journalists should all be required to read the relevant wikipedia articles before publishing something about science Or they should at least edit the relevant wiki articles to make sure it matches their article.

    • Re: (Score:3, Insightful)

      by DerekLyons ( 302214 )

      Achieving a net energy gain is not the main obstacle to making fusion commercially viable. That has been done quite successfully. There is no problem passing break-even.

      No, actually niether has been demonstrated - ITER is intended to do so. (Among other things.)

      It is ignition we are trying to achieve now. That is, a fusion reaction which produces enough heat to cause more fusion, provided enough fuel.

      No - ignition means achieving fusion. What you call ignition is called a self sustaining

      • Re:Net gain not the obstacle! (Score:5, Informative)

        by The_Wilschon ( 782534 ) on Thursday September 28, 2006 @04:42PM (#16236499) Homepage
        Go out and get yourself a copy of An Introduction to The Physics of Nuclei and Particles by Richard A. Dunlap, first edition, published in 2004. This is one of the standard texts for an undergraduate physics course in nuclear and particle physics. See pages 192 and 193, esp. Figures 13.12 and 13.13. Then read the text on page 192. I will reproduce it here for your benefit:

        In Figure 13.12 the broken line represents unthermalized breakeven. This refers to the situation where the energy output of the reactor is equal to the energy input but the plasma conditions have been augmented by neutral beam injection. The solid line represents thermalized breakeven where the plasma conditions themselves are sufficient for net energy production. The shaded region represents ignition where the energy output is not only sufficient to yield a net energy gain but is also sufficient to maintain the plasma conditions. This is a self-sustained fusion reaction. These operating conditions refer to d-t fusion; conditions for d-d fusion would follow curves with values of n\tau about two orders of magnitude larger. The data points in the figure represent the operating conditions of a number of experimental magnetic confinement reactors. The general trend of the points from the lower left to the upper right of the figure represents the chronological development of fusion reactors from the late 1960s to the late 1990s. This line also represents an increase in reactor power from the mW range to several MW. Present results are in the breakeven region and future developments can hope to achieve ignition. The time scale for such developments is presumably in the order of several decades.
        The figure shows 2 points inside the solid line, and 15 points between the solid line and the broken line. Figure 13.13 on the facing page is a similar plot, showing inertial confinement experiments rather than magnetic confinement. However, 13.13 lacks the lines showing the two breakeven points.

        Allow me to repeat the particularly relevant phrases (emphasis mine):

        The shaded region represents ignition where the energy output is not only sufficient to yield a net energy gain but is also sufficient to maintain plasma conditions. This is a self-sustained fusion reaction.
        Present results are in the breakeven region and future developments can hope to achieve ignition.
        Direct from a credible source. Now, perhaps Dunlap is wrong. Credible sources have been quite wrong in the past and will be in the future. However, you'd best have a stronger argument than "no you're a poopyhead" if you expect anyone to believe you.

        • Re: (Score:2)

          by Hays ( 409837 )
          I think you're simply reading it wrong.

          "The shaded region represents ignition where the energy output is not only sufficient to yield a net energy gain but is also sufficient to maintain plasma conditions."

          That does not imply that "ignition" = "where the energy output is not only sufficient to yield a net energy gain but is also sufficient to maintain plasma conditions"

          replace the word ignition with "trial" or "test" or "experiment" or "burn" or "fusion event"

          you wouldn't now say that "trial" = "where the e
          • In that case, how do we explain the final sentence?

            future developments can hope to achieve ignition.

            Certainly this is not as the GGP said, that ignition is fusing any two nuclei. We most certainly have done this, so why should we "hope to achieve" it?

            Furthermore, the first sentence of the next paragraph reads

            In Figure 13.13 the solid region again represents ignition for a d-t reactor.

            This again seems to support my interpretation. Unfortunately, I can't quote exactly what my professor said in cla

        • Re: (Score:3, Informative)

          by deglr6328 ( 150198 )
          I believe the GP is right. No one has actually achieved breakeven (except for Dr. Edward Teller in the 50's but those weren't exactly practical power producing devices since they tended to obliterate everything in a 20 mile radius!!). The JET in Culham UK came closest a few years back at ~70% breakeven with a 50/50 DT plasma. Those dots you are seeing on that plot are almost certainly extrapolated breakeven points. meaning they represent the DD reactions done on the Japanese JT-60 device which WOULD, if don
          • That would certainly be an adequate explanation for those dots, however it does not agree with what Dunlap says in the text. Perhaps Dunlap is himself mistaken, but since he does not cite a source for the figure, one can presume that he (or possibly a grad student of his) made it for the text, and thus he ought to understand it and know what those points actually represent. Your explanation does not, I suppose, directly contradict "Present results are in the breakeven region", but it certainly contradicts
          • Ok, I have sent an email to Dr. Dunlap. I took the liberty of quoting the following from your comment: "the DD reactions done on the Japanese JT-60 device which WOULD, if done with a DT plasma, have achieved breakeven at 125% gain. But since they have never gone to DT plasmas on that device, because they don't have the facilities to handle T, they have not strictly broken even.". I hope that you do not mind. Hopefully he will respond soon.

  • Everyone will be doing it soon... (Score:4, Interesting)

    by jbeaupre ( 752124 ) on Thursday September 28, 2006 @03:20PM (#16234905)
    Pretty soon even high school students will be making fusion reactors. Oh wait, they already are. http://en.wikipedia.org/wiki/Farnsworth-Hirsch_fus or [wikipedia.org]
  • Xinhua have an atrocious track record for truth verses spin, worse than tony blairs pr department. I'm not going to get excited about this one.

  • what they are not telling us (Score:3, Funny)

    by roman_mir ( 125474 ) on Thursday September 28, 2006 @03:25PM (#16234995) Homepage Journal
    Scientists at the Chinese Academy of Sciences announced they had successfully tried a domestically developed fusion device in the eastern Chinese city of Hefei, Xinhua news agency said.

    The scientists called the device "the first of its kind in operation in the world", but the report did not specify what tests it had passed. ...
    Xinhua cited the scientists as saying that deuterium and tritium atoms had been fused together at a temperature of 100 million degrees Celsius for nearly three seconds.     - what they are not telling us is that their sofistimacated gizmotron is based on a Yin Yang Dragon technology, which employs 500,000,000 manual workers, each one only having to heat up one atom by 1/5th of a degree by applying the power of the Chi.

    Since the labor for all the labor only cost about $5 total, the reactor was able to produce an energy surplus, a feat previously considered to be improbable.

  • Awsome (Score:3, Insightful)

    by susano_otter ( 123650 ) on Thursday September 28, 2006 @03:39PM (#16235237) Homepage
    Good for them.

    I hope the test was practical in nature, and will lead to useful contributions from China towards the achievement of practical fusion power.

    This is good news. I look forward to following China's future progress and contributions.

  • A Small Step (Score:4, Informative)

    by quanminoan ( 812306 ) on Thursday September 28, 2006 @03:48PM (#16235427)
    A fusion reactor has so many challenges behind it that ignition is only a small step towards something useful. Assuming you ignite a plasma you then have to maintain it, keep it stable, and fuel it fast enough to keep it burning. After that you're left with "mere" engineering problems, such as removing ~ 1 MW of heat per m^2 on the walls of the tokomak, making a gun fire a pellet of solid hydrogen into the plasma at one pellet per second, and finally creating a structure that can handle the intense neutron flux so the reactor can survive long enough to break even.

    Though ITER is being built soon, it's being designed as its going up. I'm involved with creating an H- ion beam to inject the plasma (called neutral beam injection). The idea is to fire a high energy beam of neutral hydrogen into the plasma to heat it up (neutral so the atoms can travel through the containment magnets without deflection).

    So even if the Chinese managed to build a reactor that beats previous records, it's a long while before fusion powers your home. Nevertheless I consider Fusion research to be one of the most important fields; it takes no imagination to understand what it would mean if nations could be powered on water.

  • In Communist China.. (Score:3, Funny)

    by ch-chuck ( 9622 ) on Thursday September 28, 2006 @03:50PM (#16235461) Homepage
    ... do they call it The US Syndrome [wikipedia.org]

  • I've read this [wikipedia.org] and this [wikipedia.org] and I'm still a little lost. Could someone with a science background please opine as to what significant hurdles scientists have faced in trying to implement fusion technology in the past?
  • Any mention of "Mr. Fusion" and a DeLorean in the translation?
  • But what exactly made this test 'successful' is not clear.
    Perhaps it confirmed the scientists' hypothesis by matching their latest, most sophisticated model: that the reaction should generate 12% as much energy as needed to heat the plasma. ;-)
  • Not only have the Chinese created a fusion reaction, they found a way to stamp it out of plastic for three cents a unit.
  • I am surprised that nobody else has taken issue with where the world's very first commercial fusion reactor will be built.

    I envision some ill-informed, or just plain stupid, french person getting upset that it will be built in his backyard. He might be afraid of high voltage power lines or something.

    I envision Spain folk complaining that they cannot differentiate between the sun coming up, and the ominous glow of their fusion brothers to the east.

    I envision German politicians wondering if any funny gasses

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