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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...
The Telegraph and several other news outlets are reporting on the international deal to build the world's most advanced nuclear fusion reactor that was signed in today. Representatives of the EU, the US, Japan, India, Russia, South Korea and China signed the ITER (International Thermonuclear Experimental Reactor) agreement in Paris, finalising the project which aims to develop nuclear fusion as a viable energy source to fossil fuels. According to the ITER consortium, fusion power offers the potential of "environmentally benign, widely applicable and essentially inexhaustible" electricity, properties that they believe will be needed as world energy demands increase while simultaneously greenhouse gas emissions must be reduced,justifying the expensive research project.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
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.)
Its a bit like the situation in Australia at the moment.
A task force reccomended that we build 25 nuclear reactors.
The greenies are saying that it'll be a environmental disaster.
What would they prefer? 25 coal power plants?
(Just if you dont know, Most of Australia's power is from coal and we have no nuclear)
they could actually, see http://en.wikipedia.org/wiki/Fusor
the difficult bit is getting more usable energy out than is put in. One important milestone on the way to achiving that is to get a plasma that will keep fusing without external heating, hopefully iter will achive this milestone.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
I'm doing my masters in fusion. Grandparent is indeed correct. The reason being, the products of the fusion reaction are regular helium, and neutrons. The neutrons will activate the building which is the source of the low level waste. So we just keep things that get really hot out of the reactor design.
Right now, after ITER's 10 year lifetime, the only components that will need to be considered nuclear waste is are the tungsten components of the first wall (the wall facing the plasma) The products of activated tungsten have a very short half life, so after a year or so, the copper heat sinks will be the hottest components, and they'll be cooler than the tonnes of medical nuclear waste that gets shipped in and out of hospitals every year. There will be no leakage as neither tungsten nor copper are water soluble. The bigger risk is a steam explosion, which has the potential to release some tritiated water and maybe some tungsten oxide (some of which would have been activated by the neutrons) into the local community. But ITER is designed, that in the worst case scenario, there would be no need for evacuation. http://www.iter.org/a/index_faq.htm Choose the safety bullet to read about this. The worst case scenario is assuming the worst possible weather conditions, and that 100% of anything radioactive that could possibly be in the reactor becomes airborne and ingestible.
The trench is an interesting idea. Mind you, the really hot nuclear waste (spent fission fuel rods) are packed full of useable uranium. They can be re-refined and used again. We just... don't yet.
Aha. Costs. I was just at a conference where they were discussing the finer points of ITER. Trust me. International funding sources + over 10 years of them bickering over costs. Decommissioning costs have been included right down to the cardboard boxes for the scientists to pack up their offices.