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Green Light For ITER Fusion Project
brian0918 writes, "A seven-member international consortium has signed a formal agreement to build the $12.8 billion International Thermonuclear Experimental Reactor (ITER). From the article: 'Representatives from China, the European Union, India, Japan, Russia, South Korea, and the United States signed the pact, sealing a decade of negotiations. The project aims to research a clean and limitless alternative to dwindling fossil fuel reserves, although nuclear fusion remains an unproven technology.' ITER will be built 'in Cadarache, southern France, over the course of a decade, starting in 2008.'" If ITER is successful, a commercial reactor could be built by 2040. Funny, I seem to remember fusion researchers from Livermore in the 70s say that commercial power was 20 years away...
Estimates of when fusion would be a viable energy source didn't take into account years of under-funding. ITER could have been done years ago.
Shut up you fucking hippies, get a haircut.
Seriously, this -is- an effort to fight global warming, and if you weren't so dogmatically opposed to anything involving OMG ATOMS!! you'd see that.
there is no need to sign your posts. this isn't usenet. your username is right there above your post. stop it.
2 did and when it is done with 1 you wont need 3 - you'll be living it.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
I worked at D3D 'way back in the 1980s, when people thought breakeven would be achieved before the turn of the millennium. If as much effort were put into electrostatic confinement (the Farnsworth fusor we keep hearing so much about) that might have actually happened. The advantage of the Farnsworth fusor is that it uses a confinement field with a divergence term!
The magnetic field has no divergence (there are no magnetic monopoles) so it is extremely difficult to confine anything -- you can only slow down the leakage. That comes with some problems -- for example, it's very hard to get anything into or out of a magnetic bottle (as in a Tokamak) unless it is electrically neutral. Accelerating and heating the plasma are hard because the energy sources you can use (manipulation of the magnetic field itself, either at radiofrequency (RF heating) or near DC (betatron heating), themselves destabilize the confinement.
D3D used the innovation of firing neutral atoms in through the magnetic bottle, which provides material and heat into the plasma (the atoms generally ionize once they get in -- and then they're trapped like the rest of the plasma). The problem there is that we have no technology to accelerate neutral particles -- so they had these little tiny particle accelerators that fired their beams through GIANT TANKS of reactant that was intended to neutralize the input beams on-the-fly. Some small percentage of the particles got neutralized, and the rest bounced off the outside of the magnetic bottle into a beam dump. Seeing the size of the equipment made me realize that tokamak fusion is probably a dead end for power generation -- if it can be made to work at all (in the sense of achieving, say, 10x heat gain), the ancillary equipment is HUGE and it's not at all clear that economies of scale are enough to make it worthwhile.
The Farnsworth-Hirsch type fusors have the advantage that you can fire in charged particles -- they rattle around and lose some of their kinetic energy, and after that they're trapped in a normal potential well. Like muon-catalyzed fusion machines, the Farnsworth fusor is in a race to get the energy out of a fusible nucleus before it leaks away -- but fresh hydrogen or deuterium ions are much, much cheaper than muons, and it seems to have a better chance of working.
(Remember muon-catalyzed fusion? Muons act like electrons, only more massive -- so atoms that have an electron replaced with a muon get smaller [it's a quantum thing], bringing the nuclei closer together and boosting the fusion rate. You can get a pretty high fusion rate (a few fusions per muon per microsecond) at close to room temperature in pretty tame materials. The problem is that muons only last about two microseconds before decaying into energy, neutrinos, and electrons -- so you have to make several hundred fusions per microsecond, to make the energy worth the effort of making a muon in the first place. Nobody was able to make it pay off.)
Why is fusion receiving such a tiny (relatively speaking) amount of funding? Why is the Western world not rushing the project. At a risk of sounding cliched, it seems to me that if the 300-500 billion thus far spent on the Iraq war had gone into fusion research, we could have 10-20 different experimental approaches (essentially, trying all the major possible reactor designs) and commercial reactors in a few years.
Not to mention the obvious superiority of spending billions educating the horde of scientists and engineers and computer programmers and managers and other technical workers that would need to be trained for a big project like this. Instead, we spend that money training young men and women how to fight and perform military tasks. The thousands of technical workers that would be produced from an all-out effort for fusion would be extremely useful in achieving the next level of technological breakthroughs.
War damaged soldiers come home, often with permanent injuries, and may never reach their potential. I am in the Army National guard, and I've seen it happen time and time again. Surprisingly few people take advantage of their GI Bill to actually finish a degree.
Oh, and the middle east would be irrelevant. Without money from oil, they would be unable to buy advanced weapons or commit international terrorism, and would basically be another degenerate culture like most of Africa. Sure, they'd kill each other : but we would be able to safely stand back and occasionally drop in food to the refuge camps.
ITER gets a lot of press, but there's an equally large obstacle to commercial fusion that it doesn't even address: the materials issues.
A commercial fusion plant is going to produce a tremendous neutron flux, orders of magnitude greater than that seen in modern fission plants. So many neutrons will be produced that every single atom in the reactor vessel is can be expected to be struck and displaced several hundred times over a 30-year life cycle, and you're actually going to get a small number of nuclear reactions that will produce minute hydrogen and helium bubbles at lattice boundaries. There are no known suitable materials that can handle that kind of neutron exposure without swelling, cracking, degrading, becoming extremely brittle, and so forth. This would be Bad.
ITER isn't going to generate the kinds of neutron flux you'd need to even explore those issues. ITER's going to generate about 3 displacements per atom, not 300. There is another facility, IFMIF, intended to research this by generating similar neutron fluxes to what you'd see in a real fusion reactor, but it's only at the design stages right now, and won't come on line for long after ITER does.
Getting the fusion right is only part of the problem, and it's possibly the easier part. It's an engineering problem. But the materials issue might not be solvable, because the right materials might just not exist.
Folks, there are huge amounts of uranium and thorium around, and we do not have time to wait until we figure out fusion to stop dumping carbon into the atmosphere. By the time we even come close to exhausting our sources of fissile fuel, we should have learned how to construct large-scale orbital structures, and once we can do that we won't even *need* fusion. It's entirely possible that commercial fusion will never happen.