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Science Technology

Mr. Fusion Comes Closer 49

doktoromni writes "The first experimental, sonofusion-based, table-top fusion reactors are now being commercially sold. Although those reactors are not breakeven (yet, would say an optimist), they are by far much cheaper than other fusion approaches, like magnetic and inertial confinement. Also, they open the possibility of portable fusion reactors, along the lines of 'Back to the Future'..."
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Mr. Fusion Comes Closer

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  • by captnitro ( 160231 ) on Tuesday December 14, 2004 @02:56PM (#11084350)
    Hey, I'm going to lunch; anybody spot me $250,000?
  • by Saeed al-Sahaf ( 665390 ) on Tuesday December 14, 2004 @02:56PM (#11084355) Homepage
    table-top

    If you have one Hell of a table. Have a look at the picture in the story.

  • by RobertB-DC ( 622190 ) * on Tuesday December 14, 2004 @02:57PM (#11084369) Homepage Journal
    Using proprietary technology, the IDI reactor is a stainless steel sphere filled with heavy water and, at its center, a small bubble of deuterium (heavy hydrogen). Sound waves cause the bubble, first to expand greatly, followed by its collapse to a fraction of its original size, all at the rate of thousands of times a second.

    How, exactly, is this "proprietary technology" supposed to help with research into new fusion methods? I know they have to make money, but does the $250k price tag include a license that if the researcher finds an improvement that builds on the proprietary part, the improvement belongs to Impulse Devices?

    Well, it's not as bad as some bozo patenting my DNA, I guess...
    • They're not clear about it, but I suspect that "proprietary technology" means that they own a bunch of patents that are realized in this device. Which means that if you make a major step, they don't own it, but if you include their device in your setup you're going to have to buy it from them or license their technology.

      That's actually roughly the way the patent system is supposed to work: you invent something, then you make it public in return for a guarantee that nobody else will make the same thing. T
      • But in this case they are making it public so they can make money. The patent system is supposed to encourage people to expose things that they would otherwise maintain as trade secrets. By selling it for cash they are being rewarded for their invention, and at the same time making thier invention public. So why should they be getting a patent? What are they giving up for it beyond what they are giving up by selling it?

        One could argue that without patents people like this would not sell their invention
        • They're getting a patent to ensure that nobody buys one machine, builds a duplicate, and then sells it cheaper. Market forces would drive the price down. You have two producers competing, but only one of whom has extensive R&D invested.

          It's not that they wouldn't sell their inventions; it's that they'd go into a different line of work entirely. R&D is expensive, and if they had no patent protection on it, they might simply go out of business.

          The pro-patent people claim that without patents, R
  • by parvenu74 ( 310712 ) on Tuesday December 14, 2004 @02:57PM (#11084370)
    What a day on /. -- first an article on the hydrogen economy, now fusion... I'm on the edge of my seat anticipating the personal hovercraft story that CowboyNeal is probably proofing as I type this...
  • I can have a car that will last on my commute (assuming a steam engine that is at least as efficient as my Escort's 4-cylinder gas engine, and my current driving habits) 961 years? Something tells me that this simply won't be that efficient- or that the car will be wrecked LONG before the Mr. Fusion runs out of power.
    • Re:So for $250,200 (Score:3, Interesting)

      by Ayaress ( 662020 )
      Well,actually, it doesn't break even, according to the article. So I suppose that even though you can get a thousand years worth of energy out of that gallon of heavy water, you'll actually have to put MORE energy into the system. It would be more efficient just to use the gas right now. However, maybe this will lead to more people researching fusion and possibly help bring about a simmilar system that will produce more energy than you need to trigger the reaction.
  • How is this thing supposed to work?
    If I read the text, I get the impression that is by means of sound wave. This reminds me of cold fusion, which seems impossible as far as I know.
    If however, I read the caption under the photo, I get the impression that it uses lasers, as in inertial confinement fusion. I can't imagine a table top version of something like that. Pictures or schematics I saw from something like that suggested a huge (size-wise) setup for lasers or condensor banks.
    So what is it?
    • Re:sound or laser? (Score:4, Informative)

      by pragma_x ( 644215 ) on Tuesday December 14, 2004 @03:51PM (#11085105) Journal
      If details seem to be a bit light, that's because it's still theoretical... and not in the way that your typical Tokamak or the ITER project is. We're talking something that isn't even proven (yet) to be fusion at all.

      And you're right: it is primarily accoustic in nature and can operate on a *much* smaller scale than your typical plasma-type reactor.

      From http://news.uns.purdue.edu/html4ever/2004/0400302. Taleyarkhan.fusion.html [purdue.edu]:

      The device is a clear glass canister about the height of two coffee mugs stacked on top of one another. Inside the canister is a liquid called deuterated acetone.

      [...]

      The researchers expose the clear canister of liquid to pulses of neutrons every five milliseconds, or thousandths of a second, causing tiny cavities to form. At the same time, the liquid is bombarded with a specific frequency of ultrasound, which causes the cavities to form into bubbles that are about 60 nanometers - or billionths of a meter - in diameter. The bubbles then expand to a much larger size, about 6,000 microns, or millionths of a meter - large enough to be seen with the unaided eye.

      [...]

      Within nanoseconds these large bubbles contract with tremendous force, returning to roughly their original size, and release flashes of light in a well-known phenomenon known as sonoluminescence.

      [...]

      At that point, deuterium atoms fuse together, the same way hydrogen atoms fuse in stars, releasing neutrons and energy in the process. The process also releases a type of radiation called gamma rays and a radioactive material called tritium, all of which have been recorded and measured by the team.


      Some suggested reading to help bridge the gap between reality and "Mr. Fusion" here:

      http://en.wikipedia.org/wiki/Bubble_fusion [wikipedia.org]
      http://en.wikipedia.org/wiki/Sonoluminescence [wikipedia.org]

      Also, googling for the above topics yields a plethora of results.
      • Re:sound or laser? (Score:3, Informative)

        by david.given ( 6740 )
        Don't forget electostatically contained fusion, as well:

        http://en.wikipedia.org/wiki/Farnsworth-Hirsch_Fu s or [wikipedia.org]

        These genuinely are small, portable, and genuinely fuse hydrogen atoms in an entirely unkooky way. (They're produced industrially as neutron sources.)

        Alas, it seems doubtful that they'll ever be useful as power sources, due to the design, but hot damn, with a bit of knowledge and some TV repair equipment you can build one yourself.

        (You know, I suspect sometimes that the big fusion research

        • Farnsworth fusors [kronjaeger.com] are fascinating devices. They are simple to design, simple to build, and they work - not as energy sources yet, though, but some people are working on it. Like you said, they made themselves a niche as neutron generators - which is a byproduct of fusion, and one of the prime indicators of it taking place.

          And yes, it's the same Farnsworth that invented the TV. He was one bright and unappreciated guy.
          • And yes, it's the same Farnsworth that invented the TV

            As opposed to the Farnsworth that is ON TV... [tvtome.com]

            Personally, I think the Finglonger [20six.co.uk] is a slightly more likely commercial product in the near term (or at least the "next 5 years" near term that desktop fusion researchers always seem fond of, but are incapable of meeting).

            Russ %-)
        • the neat thing about farnsworth fusors is that you can generate high-energy neutrons using D-T fusion
          at 14MeV which will penetrate nuclei and create new
          isotopes. For example, with the DU counterweight
          from a junked 747 as a neutron target, you can
          produce plutonium 239 in your basement. If you have
          enough capacity and energy input, you can produce
          a plutonium bomb core with no nasty difficult
          isotopic isolation phase required, such as might
          attract the attention of the IAEA or the US DoD.
      • Just what the world needs. A table top neutron source.
        I wonder how many neutrons they get out it and and what energey. It might be best to play with this from a distance.
      • For those who would like to make their own...

        Garage Sonoluminescence [physik3.gwdg.de]
    • The photo accompanying the article is not the acoustic fusion reactor they're selling.
  • by i_should_be_working ( 720372 ) on Tuesday December 14, 2004 @03:09PM (#11084534)
    sonoluminescence [llnl.gov]has not been proven to actually be fusion. It's just a lot of light and some heat in water that's been compressed by sound. much more interesting than that though.

    And they claim that this process that isn't fully understood yet will get break even fusion in 5 years? Doubt it seriously.
  • does this mean we can pull the plug on this monstrosity [llnl.gov].

    Seriously. Look at the pictures, does anyone else get the idea that this thing is WAY more powerful than any nuclear power plant..... (sans radiation of course..)
    • Do you even have a girlfriend? Do you have any idea how much power just one shower / makeup session can consume?

      Oh! The Humanity!

      I've got a GF and two girls!

      I need 5 of these!

    • Uhm, this thing consumes a lot of energy but does not produce any. NIF is build for basic research and is not a prototype of a fusion reactor. And if you shoot with this laser on a target you will get quite a lot of radiation, fast neutrons, etc.
    • Re:so.... (Score:3, Insightful)

      by deglr6328 ( 150198 )
      Yes it is way more powerful than a nuclear power plant. The lasers will produce over 500 terawatts of power, far more than the entire electrical generating capacity of the world. Though only for 5ns or so. And I dont think it's a monstrosity, a debacle maybe but not a monstrosity :o). It's actually quite a beautiful machine I think; it will compress and heat its tiny hydrogen fuel capsule to temperatures and densities greater than those in the core of the sun, igniting the plasma in a self sustaining reacti
  • The picture that accompanies the article does not appear to have anything to do with IDI or their alleged new product.

    It appears to be a device used for general ICF research at LLNL.

    This has already caused confusion in a few posters.
  • Bubble fusion (Score:4, Informative)

    by francium de neobie ( 590783 ) on Tuesday December 14, 2004 @04:31PM (#11085739)
    This could be the best thing since sliced bread if it's not a fraud. But a little searching in Google and Wikipedia gave me a bad feeling that this can be another cold fusion fiasco.

    Bubble Fusion [wikipedia.org]

    For the lazy who don't read links, here's my digest:

    This kind of fusion is, according to what the researchers claimed, a side effect of another not well-understood phenonmenon called sonoluminescence [wikipedia.org]. By passing ultrasonic sound waves into a water body with tiny gas bubbles, researchers observed the bubbles emit EM waves of frequencies well beyond the UV range, which, according to black body radiation theory, indicate a very high temperature (>10,000K) inside the bubble.

    The picture gets interesting when you can get the temperature inside the bubble to well beyond the million, or tens of million degrees range, and when you fill the tiny bubble with fusable material (like deuterium). If you succeed in doing that, you get a fusion reactor without all those monster lasers and magnets - a tabletop fusion reactor.

    All the daydreaming apart, there are only a handful of researchers buying this idea. There's one researcher Rusi P. Taleyarkhan claiming to have achieved bubble fusion, a similar experiment at Oak Ridge National Laboratory had failed to confirm his resutls.

    • oh, someone has already posted that before me, sorry for the dupe.

    • There is considerable evidence that sonoluminescence is a non-thermal phenomenon, at least in water. The conditions in the bubble are very far from thermodynamic equilibrium, so the very notion of temperature is suspect, but the indications are that the light is not blackbody radiation but rather some kind of fluorescent emission.

      This is not to say that some particles could not be accelerated sufficiently to fuse, but it's a long way from the simple "UV light -> heat -> temperature" arguement that i
  • "The technology could produce energy on a break-even basis in five years and enough net energy for electricity production in 10 years."

    Yeah, that must be the day when hell freezes over. Seriously, these 'predictions' never become true so why do people always put them in articles like this? I find it really annoying. Think about it: the only time you can say something will be finished or ready in so many years is when all the necessary technology exists and has proven its usability and reliability already.
  • Ok, now as I understand it the sonofusion only fuses the deuterium at the center. So this $200 gallon of heavy water having the equivelant of 40,000 barrals of oil's worth of energy, what does that have anything to do with what they are doing?
  • with about the same possibilities of getting your investment back,

    What you've got here is a basic piece of research gear, which keeps a team from wasting time building up equipment and backtracking through technology where others have already gone. Depending on exactly you get for your quarter-click, this might be a screaming deal for some university research department.

    Not sure I would call it "commercial".
  • That's heavy!
  • Well, it doesnt look like my brother has posted but i just thought you might want to know that he built a fusion reactor in our garage. If you read http://henryhallam.cjb.net/~henry/fusor/ [cjb.net] it it shows how he made it, and shows some pictures. It does seem to be about table-size.

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