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When will fusion work?

  1. Dec 9, 2013 #1
    Hi!

    I am just asking a question a friend of mine asked me: "When will fusion work?"

    I personly think it is not a question of if as much a question of when.

    I am a little bit lazy here but I have read the ITER information a while ago and I think they said very confidently that this new Tokamak will give more energy out than is put in.

    It would be very nice if someone competent would care to comment on the above.

    Best regards, Roger
     
  2. jcsd
  3. Dec 9, 2013 #2

    mfb

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    That is expected, but ITER won't produce electricity. The planned DEMO, to be built based on ITER results, might demonstrate the viability of a power plant, including estimates of the costs.
     
  4. Dec 9, 2013 #3

    Drakkith

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    When will fusion work? Without a sudden breakthrough, probably about 50 years from now.
     
  5. Dec 10, 2013 #4
    As a fusion researcher the honest truth is that nobody knows, but unless there are major changes/breakthroughs its not going to be any time soon. There are technological issues, but there are also political and economic issues. Currently some European (Germany) and Asian (China, Korea, Japan) countries are serious about developing fusion as a power technology. They are the ones building the next generation research facilities that are needed to support ITER. IMO it is the future policies of these countries that will likely dictate when fusion will work.

    There is a lot of angst in the US fusion community with regards to ITER. Yes we expect that a tokamak with ITER's parameters to ignite. But the story isn't that simple. We know that ELM's and disruptions are going to be problematic. Both of which have potential to cause major damage. Avoiding or mitigating these events is essential to the success of ITER, and they are major thrusts of research. While there are a number of promising solutions, there are currently no guarantees! There are also serious concerns about first wall materials. The inside of a burning tokamak is an incredibly harsh environment, and there are few if any known materials that can withstand that environment for long periods of time.

    I just want to stress that there are no plans for DEMO. DEMO is just an idea, and the necessary "objectives" of DEMO differs greatly. For example you mention demonstrating economic competitiveness. I'd argue that as an experimental power plant, DEMO is likely going to have a lower duty cycle. It is also going to be a unique first of a kind facility. Both of these are going to greatly increase its cost of electricity. As a result DEMO is inherently poorly suited to demonstrate the economic feasibility of fusion.
     
  6. Dec 10, 2013 #5

    cjl

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    Fusion is 50 years away, just like it was 50 years ago...

    :tongue:
     
  7. Dec 10, 2013 #6

    PAllen

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    As someone fascinated with controlled fusion from the 1950s (thinking, circa 1960, in elementary school, that laser ignition of lithium deuteride pellets was the way to go - for some reason I was quite confident of this :redface:), my perception is that the time between now and commercial fusion has slowly increased over time. In 25 years, then 30 years, then 40, then 50 ...
     
    Last edited: Dec 10, 2013
  8. Dec 10, 2013 #7

    What would the world be without pessimists? :)
     
  9. Dec 10, 2013 #8

    PAllen

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    Of course, in the absence of being in the "Nuclear Engineering" forum, we can give many silly answers to the question "when will fusion work"?

    1) It has worked fine for nearly 14 billion years.
    2) Man made fusion has worked fine for over 60 years for some (MAD) purposes
     
  10. Dec 10, 2013 #9

    PAllen

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    Fusion is the ultimate counterexample to those who say that any technological breakthrough comes sooner than expected. This attitude is nothing but a case of selective memory - many times yes, many times no, sometimes with a vengeance.
     
  11. Dec 10, 2013 #10

    mfb

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    Let me rephrase that: it appears on timelines, andthere are estimates how some important parameters would look like.

    I said DEMO should help to do that estimate. I did not say DEMO would be such an estimate itself.

    50 years ago, scientists planned with more money.
    If you cut funding, timelines extend (or stay constant even with scientific progress). That is quite natural.
     
  12. Dec 10, 2013 #11

    PAllen

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    I don't think that is very relevant. Many other technologies came sooner than expected despite politics of funding. Further, funding for fusion only decreased after multiple predictions failed. To my mind, predicting future technology you have a range of possibilities:

    - something unforeseen makes a challenge much easier
    - development goes roughly as guessed
    - something unforeseen makes progress harder than expected

    Examples of the first are numerous and obvious. I would say rocketry is an example of the second case. Fusion is the clearest example I know of for the third case. True AI is perhaps another, but for that, there never was a consensus of expert opinion. For fusion, it really seemed less difficult 50 years ago than today.
     
  13. Dec 10, 2013 #12

    mfb

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    I don't doubt that fusion has some unforeseen problems. I just think they are problems that new fusion test reactors can solve, and that we see the same for solved issues in the past.
     
  14. Dec 12, 2013 #13

    russ_watters

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    Frankly, at this point I wish fusion (and solar and wind and clean coal to lesser extent) would just go away. Hope for these Salvation technologies steals focus, funding and political capital from fission, which is a significantly underutilized Now technology.
     
  15. Dec 12, 2013 #14

    mfb

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    I like fission, but it has some acceptance problems in many countries.
    It is not more dangerous than some other types of electricity production, but it is way easier to induce fears and bad news about it.
     
  16. Dec 12, 2013 #15
    I kind of agree with you here. But fusion would be cleaner and hydrogen is abundant.

    As the situation is right now I am actually longing for some politically incorrect power company to claim that they are only supplying fission power.

    Best regards, Roger
     
  17. Dec 12, 2013 #16
    This is the fallacy of the current enviromental movement. They've blocked construction of new fission plants, and then site 50 year old technology as examples of why we shouldn't be building fission plants. (The same goes with oil pipelines but thats off topic)

    I can't remember the chaps name, but I think its telling that one of the most ardent anti-fission activists in the 70's has done an 180 switch and now supports them whole heartly.
     
  18. Dec 12, 2013 #17
    It is a strange thing with these transmutation reactors. They seem to exist but noone talks about them. I wonder why because what they do is that they make hazardous nuclear waste less hazardous by some genious means.

    May the lack of discussion come from the fact that things are still and simply radioactive?

    Best regards, Roger
     
  19. Dec 12, 2013 #18

    mfb

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    What do you mean with "this"?
    Your post is just another argument why nuclear reactors are not as problematic as they are perceived by many.

    They do not (yet?).
    They would reduce the amount of problematic nuclear waste.
     
  20. Dec 13, 2013 #19

    Student100

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    I'm mostly surprised that the government took as long as it did here in the US to cease LENR funding.

    The Fukushima disaster hasn't helped fission one bit.

    I thought 30 years was the standard for when fusion would become viable for net power generation? Has there been any more breakthroughs since the paper on "pockets of impurity" was published? I think that was like three years ago.
     
  21. Dec 13, 2013 #20
    Because I'm a lazy guy and would like to put it on the table, I wonder when ITER will be operational (test-wise, that is).

    Best regards, Roger
     
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