7 ms·

How Seawater Can Power the World

• bluedanieru 15y ago
  >A rough estimate is that it would take $30 billion and 20 years to go from the current state of research to the first working fusion reactor. But put in perspective, that sum is equal to about a week of domestic energy consumption, or about 2 percent of the annual energy expenditure of $1.5 trillion. Millions of years from now after the human race fails and alien archeologists are picking apart the carcass of its long-dead civilization, they are going to find an enormous number of exactly these circumstances. From education to space travel and power generation this kind of folly is so ubiquitous that it is more newsworthy when it doesn't happen. There must be some aspect of human and group psychology that ensures it. As such it's hard to have much hope for the future. Just kidding about the aliens though. It's unlikely any would ever discover our ruins.
  • jerf 15y ago
    If you assign a 100% probability that $30 billion and 20 years would produce this 100% certain fantastic payoff, it looks irrational. If you put more realistic probabilities in (hint: substantially less than 100% in both cases), and then realistically account for all the other things going on and their realistic probabilities of success and the values when they succeed, human behavior looks a lot less irrational. Maybe not entirely rational, but certainly not blindingly stupid.
  • iwwr 15y ago
    Large infrastructure projects are wasteful no matter how you cut it, so at least they should have precise objectives (much shorter than 20 years) and per-objective pricing (rather than cost-plus).
    • bluedanieru 15y ago
      How are they wasteful 'no matter how you cut it'? What if the cut is more efficient energy production, or access to plentiful resources, or freeing the fate of humanity from the fate of its home planet (everyone here should appreciate separation of concerns). And why twenty years? Why rule out a concrete multi-generational goal (assuming humanity can ever achieve that level of social organization first) which has a large payoff and reasonable chance of success?
      • iwwr 15y ago
        Why rule out a concrete multi-generational goal? The project would be doomed to failure without intermediary objectives. Long term planning is difficult as it is and politics adds to the implausibility.
• rbanffy 15y ago
  I wonder why so many people insist that there has to be a "winning" technology. So someday all of the world must commit to generate energy from nuclear fusion (despeite the horrendous cost and quite modest results scientists have to offer for the money spent) rather than harnessing the cheapest easiest energy sources around. Big Fusion (ITER style) looks more like a government program to employ physicists than anything really practical, something like "we already spent so much on this it would be foolish to stop now". Not to mention the writer forgets there are countries without seashores. How are they supposed to generate their energy in this fusion-driven utopia?
  • demallien 15y ago
    What would you suggest as an alternative base load technology?
    • rbanffy 15y ago
      I would go for thorium fission. As it seems, it's orders of magnitude easier to implement than deuterium fusion. Fusion is safer, I agree, and we should not abandon the research, but developing a thorium cycle for now instead of betting money on an uncertain approach to energy generation is, IMHO, smarter. As a civilization we need more energy (and, if climate changes faster, we'll need more) and we need on a predictable schedule. Fusion has been about the same number of decades (two) away since I was a young boy. I don't think it deserves the faith we are depositing in it. Much like space colonization and jetpacks, it is a broken promise. I'd also not forget other alternatives like molten-salt solar, hydro, wind and even photovoltaics that can offset some of the needs for power generation.
• Zak 15y ago
  Fusion power has been 20 years away for the past 50 or 60 years according to the top scientists in the field at the time. I suspect there's a good chance that in 20 years, it will still be 20 years away.
  • Retric 15y ago
    I would argue that Fusion power has been 20 years (aka 2 power plants) away after we built JET in 1983. Except, we never actually built the next fusion power plant. Based on past progress I would estimate Fusion as a useful power source is 50+ years away. However we could build a net energy gain Fusion power plant today just using the scaled up ITER plans that we scaled down to useless levels. At this point the real issue is cost and Fusion is useless unless it's cheaper than wind power. Edit: You can see actual progress on ITER http://www.iter.org/doc/all/edit/img_galleries/chantier_25.05.2011-aif.mj_edited.jpg http://www.iter.org/doc/all/edit/img_galleries/chantier_25.0... But, wait that's just an amphitheater the actual fusion power plant is still a hole in the ground http://www.iter.org/doc/all/edit/img_galleries/dsc_0767.jpg http://www.iter.org/doc/all/edit/img_galleries/dsc_0767.jpg (June 2011). PS: The US program has been derailed by attempts at fusion using lasers which had nothing to due with power plants and everything to do with simulating bombs. As to Europe they are just really slow Japan did make some interesting progress but they don't really allocate the money to fund such things.
  • maeon3 15y ago
    I hear the statement: "Technology T is Y years away", all the time, it is usually is just speculation and wishful thinking. I would rather people replace that overused line with the statement: "Technology T has barriers B, C and D preventing its successful implementation and mass production". Leave feel-good speculation out of it and focus on overcoming the obstacles.
    • SoftwareMaven 15y ago
      I would imagine talking to lay-people in terms of road-blocks instead of hypothetical times would cause a net reduction in funding, and these kinds of articles are all about funding.
• ern 15y ago
  If Asian countries are enthusiastically funding the research, why couldn't the US just license the technology after it is developed?
  • uvdiv 15y ago
    How would the director of the Princeton Plasma Physics Laboratory benefit from that?
    • jrockway 15y ago
      Version 2.0.
  • hristov 15y ago
    We could and we would end up much poorer than those Asian countries. They would make the licenses such that the majority of the benefit would go to them.
  • bluedanieru 15y ago
    That is exactly what would happen. Or we'd steal it. Either way the US is not on the cutting edge.
    • rbanffy 15y ago
      Why would anyone want to be on the cutting edge of a very uncertain technology development. I would believe the "It's 20 years away" figure if, 20 years ago, the same folks would have said we were 40 years away, instead of 20. I heard the 20 number a lot and I have seen very little actual progress beyond successive discoveries that the problem was much harder than they thought. Why not try to be on the leading edge of something with practical applications 5 years down the road (like the thorium cycle, for instance)?
      • bluedanieru 15y ago
        Why would anyone want to be on the cutting edge of a very uncertain technology development. To push forward the state of the art? Sure, you can wait for someone else to do it for you, but you give up quite a lot in doing so. Namely: you pay a premium for the technology having not taken the risk, you lack local expertise with the technology as it was developed externally, you will suffer knock-on effects in unrelated areas as research and development resources move to where there is demonstrated ease of funding. Note that you suffer the last one regardless of whether the investment is actually successful.
• trebor 15y ago
  I keep hearing "fusion" and keep wondering if we shouldn't go for the thorium route first. It's safer than fission w/uranium and can even be taught to third world countries without fear of giving them nuclear bombs.
  • iwwr 15y ago
    Less proliferation risk, but not zero. It's still possible to build a bomb from U233 (obtained from the thorium cycle).
    • ams6110 15y ago
      At this point in time, how much additional risk does it add though? Any nation-state that is bound and determined to develop nuclear weapons pretty much just does it (e.g. Iran, North Korea) and the supposed anti-proliferation watchdogs (UN, IAEA) pretty much just stand on the outskirts and say "please stop," which has about as much effect as you'd expect.
      • iwwr 15y ago
        The thorium cycle is a higher technological level and more expensive to develop, so a state capable of developing one is more than capable of a conventional uranium bomb program.
        • trebor 15y ago
          But the way I understand it is that Thorium-based fission is more costly to weaponize than uranium, or plutonium based fission. Might be more technical, but it should be able to be operated without such a high technological level. So you could sell a system to a third world country without a great deal of concern over their nuclear capabilities.
• yaakov34 15y ago
  After actually looking at the numbers and the details regarding fusion technology, I've come to the conclusion that the advantages over fission are illusory. I think people believe that fusion is somehow "way more powerful", because they know that fusion bombs are way more powerful than mere atom bombs. Actually, in many of the most powerful fusion bombs, the vast majority of the energy is produced by fission, with fusion serving as only an intermediate step to release neutrons and create more fission. A step you don't need in a reactor, which can control the fission rate itself. My guess is that a lot of people who haven't looked at the numbers think that fusion is hundreds of times more powerful than fission. Well, let's look at those numbers: the fission of a uranium-235 atom produces 202.5 MeV. The fusion of D+T produces only 17.6 MeV. That's more energetic per unit mass of fuel, since D and T are just hydrogen isotopes, but if you do the math, it's only about 3.5 times more energetic even using this measure. And fuel mass is a tiny portion of the mass of the whole powerplant. To make it worse, hydrogen is far less dense than uranium (by a lot more than a factor than 3.5), so you actually end up with a lot more fuel volume and containment volume. There are other reactions than D+T, but none of them look as good as plain old fission. That's before we even get into the fact that for most fusion reactions, a lot of the energy goes into extremely dangerous neutrons. The talk about "getting the fuel from seawater" is also misleading. It's technically true, but the process is very expensive, and, if we are going to talk about seawater, uranium can also be extracted from it. Finally, the idea that the danger from proliferation would go away is also false - anything producing a neutron flux as strong as a fusion reactor can be used to produce isotopes suitable for a bomb. And even aneutronic fusion (which is technically even more difficult) can be made to produce neutrons with suitable additions to the fusion fuels. EDIT: P.S. I am not an expert. I do think I can understand numbers and technical arguments, and I would love to hear expert analysis. But one thing: for every technology which you assume will help fusion (such as wonder-containments for the neutrons), please analyze how fission reactors would benefit from it, as well. Then let's see if we can make fusion come out "better" than fission in some meaningful sense. EDIT: I can't resist adding that the talk of "harnessing the reaction that powers the Sun" is aimed at people who don't know the numbers, and is very annoying. The Sun is not a good model; it has a huge mass (duh), and a tiny surface-to-mass ratio, which is why the energy it produces makes it so bright. But pound-for-pound, the Sun produces a lot less energy than slightly warm chicken soup. Do the math yourself, and be surprised. We can not build a reactor that works like the Sun.