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Science Technology

How Close Are We, Really, To Nuclear Fusion? 399

StartsWithABang writes: The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion. The same process that powers the core of the Sun could also power everything on Earth millions of times over, if only we could figure out how to reach that breakeven point. Right now, we have three different candidates for doing so: inertial confinement, magnetic confinement, and magnetized target fusion. Recent advances have all three looking promising in various ways, making one wonder why we don't spend more resources towards achieving the holy grail of energy.
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How Close Are We, Really, To Nuclear Fusion?

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  • the real question (Score:3, Interesting)

    by slashmydots ( 2189826 ) on Saturday August 29, 2015 @02:01AM (#50414463)
    Can any of the three methods fuse practically any matter like a Mr Fusion? Or do they all take ultra-pure atom mixes or tritium or something else ridiculously hard to get?
    • Nothing can fuse "practically any matter", at least and get energy output. As elements get heavier, you get less energy out of fusing them. The breakeven point (with the exception of a few exceptional isotopes a little further up) is iron. Past iron you have to put in energy to get fusion. Heavier elements produce energy when they split up, which is why nuclear fission is a thing and is done with very heavy elements.

    • The farther up the Periodic Table of Elements something is, the more energy required to 'fuse' it into a higher element; all the elements in the Universe heavier than helium happened when stars when nova or supernova. 'Mr. Fusion' is total fantasy. Also, as someone else already mentioned, hydrogen is the most abundant element in our Universe.
  • 30 years (Score:4, Funny)

    by LogicLoop ( 1186965 ) on Saturday August 29, 2015 @02:03AM (#50414465)
    30 years. Didn't you get the memo? It came out 40 years ago.
  • by cyn1c77 ( 928549 ) on Saturday August 29, 2015 @02:04AM (#50414469)

    I would say roughly 1 AU, but it varies with the elliptical orbit of the earth.

  • by Snufu ( 1049644 ) on Saturday August 29, 2015 @02:11AM (#50414477)

    year() +10;

    • There are only two hard things in Computer Science: cache invalidation and naming things.

  • 1) It's not the holy grail. It's been shown that if our energy consumption continues to grow along its current trajectory, then the temperature at the surface of the earth will reach the boiling point in several hundred years. Now, presumably the growth of our energy consumption will slow down at some point. But what this thought experiment demonstrates is that any power source that generates denovo heat on the earth is part of the problem. Ultimately, the source of our power will have to be the sun.
    2) Even

    • With cheap, abundant energy, we'll be able to ship excess heat off-planet.
    • by khallow ( 566160 )

      1) It's not the holy grail. It's been shown that if our energy consumption continues to grow along its current trajectory, then the temperature at the surface of the earth will reach the boiling point in several hundred years. Now, presumably the growth of our energy consumption will slow down at some point. But what this thought experiment demonstrates is that any power source that generates denovo heat on the earth is part of the problem. Ultimately, the source of our power will have to be the sun.

      Solar also generates heat since it is increasing the albedo of a part of Earth and the result electricity produced will generate heat through work or inefficiency.

      And physical exponential growth forever is not a serious scenario to consider.

      • Albedo

        Please google that word. Then, if you can, explain what you mean when you say "Solar also generates heat since it is increasing the albedo of..."

        Perhaps that would provide me with an incredibly important insight that could herald a breakthrough in physics. But alas I fear that any attempt to explain that choice of words will fail, and I will remain stuck with the same old physics we've had since Einstein shook things up a bit over a century ago.

    • "Ultimately, the source of our power will have to be the sun."

      No, going all solar would not be a way around the ultimate heating problem. First, every solar panel 'blackens' its tiny patch of the Earth, this being an area of lower albedo. Then you get the same waste heat from consuming PV electricity as you would get from electricity generated any other way.

      In any case, the thermodynamic heating problem has nothing to do with carbon warming and is minuscule in comparison to trapping of solar heat by greenho

  • by JanneM ( 7445 ) on Saturday August 29, 2015 @02:15AM (#50414483) Homepage

    Achieving practical nuclear fusion for power generation would be a very nice step forward. But "holy grail" is rather overselling it, I suspect.

    Even when practical, we're still talking very big, very expensive plants that depend on a long supply chain for all its parts, the high-purity fuel and so on. When you consider the building, running and maintenance costs, and the cost of dealing with the spent fuel (much better than for fission plants of course) the energy won't be all that cheap. Hopefully cheaper than fossil fuels at least, but I would not be surprised if a first generation of plants, at least, become more expensive than that.

    And they'll be competing with rapidly dropping costs for solar and other renewables. A big, expensive plant like that will need a 40-50 year lifetime to pay for itself. If you can't show that it will likely run profitably for that time period few or no companies will be willing to take on the very major investment. We may well see a technical breakthrough for fusion, and still get no plants actually built.

    • by bugs2squash ( 1132591 ) on Saturday August 29, 2015 @02:35AM (#50414511)
      No problem disposing of the fusion by-products; just fuse H + H to make He, He + H to make Li then fuse Li + Li to create a non-fossil source of Carbon then burn it. Its the clean coal technology we've been hearing so much about.
    • by Maow ( 620678 )

      Achieving practical nuclear fusion for power generation would be a very nice step forward. But "holy grail" is rather overselling it, I suspect.

      Even when practical, we're still talking very big, very expensive plants that depend on a long supply chain for all its parts, the high-purity fuel and so on. When you consider the building, running and maintenance costs, and the cost of dealing with the spent fuel (much better than for fission plants of course) the energy won't be all that cheap.

      And they'll be competing with rapidly dropping costs for solar and other renewables.

      Quite - almost any tech advances that will help fusion will also help other energy sources.

      And the cost(s) would be unbelievably huge. Multiple times a fission reactor's cost.

      I found this story quite interesting - and disappointing. Essentially argues that we'll never have fusion and gives his (Maury Markowitz's) reasons for it: Why fusion will never happen [wordpress.com].

      For me, this seems to capture the gist of his argument nicely:

      You can argue all the technical superiorities of fission over wind all you want –

      • by dbIII ( 701233 )
        Yes that has been clear since the early 1980s but for some reason the hippies get blamed for the lack of nuclear power instead of the bankers.
        Most of the people who know how to build components of nuclear reactors have retired. Any serious effort is going to take years even if money is found.
    • Even if you could say with certainty that in 10-20 years the practical technology could be established, wouldn't you be looking at another 30+ years before it was actually a meaningful force in power generation, making fusion more like 50+ years out?

      Say they solve the technology hurdles in 10 years. They will then need to build a test plant that operates at a scale large enough to generate meaningful power (a few megawatts). That would probably take 10 years. That plant would need to run for, what, 5 yea

    • But "holy grail" is rather overselling it, I suspect.

      Even when practical, we're still talking very big, very expensive plants that depend on a long supply chain for all its parts, the high-purity fuel

      1. That is not necessarily true. It's probably true for the near future, but AFAIK not fundamentally.

      2. Solar is fundamentally dependent on accessible sunlight in copious amounts. I was recently made aware that in the event of a supereruption or other incident that decreases incident sunlight worldwide, a society mainly dependent on solar energy would have immediate and serious power issues. Besides that, solar becomes less useful the farther away from a star you get. Finally, solar fundamentally scales wit

    • Even when practical, we're still talking very big, very expensive plants

      That's actually not true. When you look at the Lockheed Martin Compact Fusion Reactor [lockheedmartin.com], it's being designed to be small enough to fit on an airplane. It's a lot bigger than a "Mr. Fusion", but compared to a typical fission reactor, it's tiny.

      • If L-M had a compelling case that they could deliver what they say, on the budget they claim, they wouldn't be begging for money -- the big utilities that have spun off their generating components would be lining up to provide the funding. Hell, the states of California and New York would provide funding. That L-M is begging says a lot about the quality of the information they can actually show.
  • It can already be done (Teller etc), it's just scaling it down to a manageable scale that's the problem.
  • This comes up now and again here on Slashdot. Maybe we should have a wiki or something "Frequently Asked Questions" or something

    Fusion is always 20 years out, and there's a reason for it. this image [wikimedia.org] sums it up nicely.

    Essentially, we could have fusion power in about 20 years if we had the political will to think 20 years into the future and fund it.

    Since fusion research won't yield results before the next election cycle, no congresscritters will vote for it.

  • by phantomfive ( 622387 ) on Saturday August 29, 2015 @03:17AM (#50414603) Journal
    This graph explains very clearly [imgur.com] how far away we are, and why it is taking so long. The reality is, with all the cheap coal (and natural gas), it's just not a priority. Besides, environmentalists hate nuclear so it's not a political winner to fund it. This story is good, too [slashdot.org].
    • by dbIII ( 701233 )
      Ta - worth bookmarking.
      It reminds me of the Synroc nuclear waste encapsulation project - completed apart from quality testing in 1988, fully complete after funds were finally found a couple of years ago proving that the technique developed before 1988 was effective enough to be used, and now it's finally in use. Using that or similar would have meant no spent fuel rods from many years before in drying pools adding to the complete fuckup at Fukishima.
    • How cheap is coal and natural gas when you factor in the cost of, in the long run, destroying all life on Earth and the Earth itself? Or do these equations only assume 'during the lifespan of the person doing the calculations'? Also your 'environmentalists' don't want any power generation of any kind, not even wind or solar, and by the way need I remind you that many of them secretly (or not so secretly) think that the best thing for the environment is if we (the human race as a whole) weren't alive anymore
    • This graph explains very clearly [imgur.com] how far away we are, and why it is taking so long. The reality is, with all the cheap coal (and natural gas), it's just not a priority. Besides, environmentalists hate nuclear so it's not a political winner to fund it. This story is good, too [slashdot.org].

      That looks like a graph that says 'fusion researchers want more money.' I want more money, too.
      If I go to the source report, will it tell me:
      1) the technical challenges they face?
      2) if they're engineering problems requiring great expenditures?
      3) If they're scientific research problems with uncertain outcomes?
      4) If the research for a #3 problem involves a massive #2 effort?

  • by Hognoxious ( 631665 ) on Saturday August 29, 2015 @04:16AM (#50414725) Homepage Journal

    How close are we, really, to StartsWithABang growing some hair, shaving off that ridiculous beard, and getting a proper job?

  • Cannot scale anyway (Score:3, Interesting)

    by Antique Geekmeister ( 740220 ) on Saturday August 29, 2015 @04:25AM (#50414741)

    I've explained this on Slashdot before: Even if such plants reach "break even", creating more available energy than they use to run, they can't possibly scale to production use because the tests that are even _slightly_ successful use tritium as a critical fuel component. And the only viable source of tritium is ordinary nuclear fission reactors: there is no scalable natural source for it.

    There is _no_ fusion technology ever tested, nor realistically proposed that does not rely on tritium. And every source of tritium itself, either earth-bound fission or potentially solar sail collectors for solar tritium, is _itself_ far more efficiently used as a straight power supply by itself. Sustainable fusion is interesting as a technological accomplishment, but it's not a viable power source unless the need for tritum is eliminated.

  • by rossdee ( 243626 ) on Saturday August 29, 2015 @04:35AM (#50414767)

    about 8.3 light-minutes

  • by benjfowler ( 239527 ) on Saturday August 29, 2015 @06:21AM (#50414991)

    Besides my own personal interest in fusion, what really excites me, is the chance to finally destroy Saudi Arabia. These worthless Bedouin brigands do and contribute nothing besides sitting on top of their Allah-given oil (which they can't extract without Western technology anyway), yet they attack, bully and undermine the world at every opportunity.

    Fusion won't ever be "too cheap to meter". However, it scales limitlessly, unlike just about every other energy source out there. And this is excellent news for Western civilization, which currently faces real constraints on how much energy it can generate and consume (renewables aren't dense; fossil fuels are unsustainable and ruin the environment; fission nuclear is dirty and dangerous, etc).

    When fusion power plants are finally in production and being scaled up, we will no longer be forced to tolerate these barbarians. At this point, we should cut the savages off without so much as a cent or a trinket.

    • by maeka ( 518272 ) on Saturday August 29, 2015 @07:32AM (#50415087) Journal

      Besides my own personal interest in fusion, what really excites me, is the chance to finally destroy Saudi Arabia

      Don't worry. With sub $40 oil Saudi Arabia has far less than 5 years of cash left. OPEC is gone, US frackers keep cutting production cost quickly moving shale oil from mid-price to low-price, and so the chance of seeing 60 oil (S.A.'s break-even point at the current level of government spending) before 2020 is slim slim slim.

      It's not that S.A. can't produce oil and make money at $40, it's that they can't maintain their stability spending at $40. Love them or hate them, they are a stabilizing force in the region. With them gone or impotent the region is going to change, fast.
       

      • Love them or hate them, they are a stabilizing force in the region. With them gone or impotent the region is going to change, fast.

        Exactly. Why anyone would want to see the Middle-East destabilized even further by 'destroying Saudi Arabia' is beyond me.

        The best thing that could happen is for countries that mainly depend on the sale of oil to gradually reform their economy and wean themselves off their oil income while they still have the cash to do so (too late, Venezuela). The world already has enough crappy economies to deal with.

    • by hey! ( 33014 ) on Saturday August 29, 2015 @09:19AM (#50415365) Homepage Journal

      Not everyone in Saudi Arabia are bedouin; in particular the ruling House of Saud is descended from town dwelling Arabs.

      I'll go out on a limb and guess that not everyone in Saudi Arabia is worthless. Even people involved in managing their oil. And as for the elite they don't seem to be worse than anyone else who's inherited oil-based wealth; they've managed that for the long term benefit of themselves and their families. If they're ostentatious with their wealth, well they have a lot of it and it hasn't bankrupted them yet.

      So there's no rational reason to want to destroy Saudi Arabia. But there's every reason not to want to be so dependent upon them.

  • Nuclear Fusion is 1AU away. Start figuring out more efficient collection methods. The bio method has proven to work, but it wastes a lot of energy in extraction of the stored energy.
  • if only we could figure out how to reach that breakeven point.

    Just accumulate enough matter together to create a gravitational field so strong that it begins to collapse space-time and fusion will start all by itself. Until we give up the notion that we can do with magnets what gravity can do (false) and that anything on a large scale must be capable of being replicated on a small scale (also false), people and governments will continue to throw money away at "fusion".

  • "The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion."

    Not since the 1980s when we realized any machine able to harness it would cost more than we could afford to pay for it.

    "The same process that powers the core of the Sun could also power everything on Earth millions of times over"

    Indeed, and if we build solar panels at the rate we are now, we'll do just that.

    "Recent advances have all three looking promising in various ways"

    Really? Let's see:

    - magnetic confinement - a

    • by johanw ( 1001493 )

      Inertial confinement is just fusion bomb research wrapped up in a nice story. Tokamaks might work in the future (JET already reached physical break-even, ITER will probably reach technical break-even) but they'll have so much engineering issues (mainly because the hull will become very radioactive) that the remaining power will probably be so expensive that wind and solar will be the much cheaper solution.

  • For anybody who's more in the know than me, what's the latest with Lockheed's supposed Skunkworks compact fusion reactor? There's so little info on it I'm inclined to think it's a pie-in-the-sky bid for government pork, but if there's been any recent updates I'd love to hear it.

  • $30 billion away (Score:4, Insightful)

    by kellymcdonald78 ( 2654789 ) on Saturday August 29, 2015 @10:33AM (#50415609)
    About $30 billion away. When the predictions of fusion being 20 years away were made, they were based on there being an adiquately funded research program. Since then we've spent less than what was projected as the "fusion never" scenario, which lo and behold is what we've got. Even ITER took 20 years just to figure out who was going to pay for it (first proposed in 1985)

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