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Giant International Fusion Reactor Draws Nearer
nnnneedles writes "BBC is reporting that scientists are deciding on where to build the world's first big fusion reactor. The international effort is described as the boldest nuclear initiative since the Manhattan Project, and holds promise for future unlimited, clean energy. The choice on where to build the reactor currently stands between Japan and France, but apparantly, the U.S. is opposing a french site because France opposed the war in Iraq." There's also an AP story.
Last time I checked, Canada, Russia and China preferred the Japanese site. And I seem to recall they all opposed the Iraq War.
The site selection has nothing to do with anyone's position on Iraq or else France would have the support of the other countries as well. As it stands, they only have the support of the EU for typical reasons.
-- You see, there would be these conclusions that you could jump to
which uses enormous power hungry electromagnets to compress hydrogen to the point at which it fuses. Unfortunately, this means that even if it is actually capable of producing more power than it consumes (like they claim on the web site) it will be monumentally inefficient compared to more modern fusion reactor designs, like the zMachine
ITER is not for practical power generation. The article says:
"Its goal will be to produce 500 megawatts of fusion power for 500 seconds or longer during each individual fusion experiment and, in doing so, demonstrate essential technologies for a commercial reactor."
It's only a demo. Fusion won't be practival for some time to come, if ever.
Long live Schrodinger's cat...
You might have a point, if this reactor were intended to SUPPLY energy for a large area.
It's not. This is apparently an experimental reactor. We haven't made this work yet; this reactor is being built so we CAN make it work through experimentation. After that, I would imagine all the countries will simply build their own reactors to supply their countries (and neighbors who wish to purchase energy and/or share in the construction costs) with energy.
What did you think, we'd build one reactor and supply the whole world with energy? Please. At the very least each country will want their own simply so their energy source simple to guarantee the existance of their own energy in case of war or natural disaster.
If this technology WORKED, you think the US in particular wouldn't drop $10bil on it in a heartbeat to build it ourselves? It doesn't work yet, and that's why we all want to build this experimental reactor.
Sorry, I took a Natural Disasters class last semester and it was awesome. You can get back to your topic now.
excuse me but why is this modded +5 informative? The Z-machine is no more modern than 10 years more modern than the tokamak and it sure as hell isn't efficient (in terms of fusion production) by any means. It's barely producing a million neutrons in its implosions; billions of times less than the energy input into the implosion.
- "Hear that?! The percolations are imminent! Cease your ingress!"
Indeed, but this project is explicitly designed to be the next "scale up" towards that goal. A design goal of 500MW of fusion power output is nothing to sneeze at....
On the other than, practical fusion is much further away than is advertised, since it requires fusing helium 3, which doesn't produce neutrons, but is a lot harder to fuse. Otherwise your reactor's atoms are slowly transmuted into other (frequently radioactive) elements as it runs. We also have to get a good source of helium 3 ("They're going to strip mine the moon!" the enviros are already whining).
As far as site selection, why not go with the Japanese? After all, back in 1979 Tomino did the first Gundam anime series, and part of its background was small fusion reactors running on helium 3, allowing for a) lots of power, b) big explosions if one can't shut down properly (this is explicit from the beginning), and c) a Jupiter Energy Fleet for the helium 3 (modeled on the petro-rich Arabs --- remember that Japan has to import all of its oil, and I think most of that comes from the Middle East) which is always behind each war, pulling the strings (with the exception of Zeta Gundam where one of them actually showed up; get it when it comes out next year in the US, it's very good)).
This is not a 'claim'; several Tokamaks have acheived 'break-even' on energy-in vs. enevergy-extracted, notably the SPHERE project from Rutherford Appleton Laboratories, IIRC.
James F.
The radiation released from the reactants would be negligible. The core itself would be highly radioactive due to neutron emission, but a cracked core could be contained comparatively easily. (The nuclear reaction itself wouldn't continue as it needs to be maintained by laser beams (or whatever this reactor uses) which would turn off veery quickly.)
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
The most viable known methods of generating and sustaining fusion both use and generate radioactive material.
The best fuel for igniting fusion is a tritium/deuterium mix because it fuses at a lower temperature. Tritium is a radioactive form of hydrogen with 2 additional neutrons. It is "bred" from lithium, but it's still a very radioactive substance. Technically speaking, fusion reactions do use radioactive material as fuel. DD reactions are possible, but they require higher temperatures and are less likely to be viable.
Secondly, the DT reaction emits neutrons. It's a simple matter of math - you have a deuterium and tritium nucleus which collide and produce helium. There's a neutron left over, with high amount energy and no electric charge. It will "ping" right out of the magnetically confined plasma. Most such neutrons will be absorbed by the lithium shielding (creating more tritium) but some will fuse with other parts of the reactor, creating, you guessed it, radioactive waste.
Commercially viable fusion reactors, if they ever exist, will almost certainly produce radioactive byproducts. It will be a great improvement on fission power, as there will be less waste in total with a shorter half-life, but radioactive waste is radioactive waste. Like fission waste, fusion waste will be expensive to deal with and be around for many generations.
For more info, here's a link to the Wikipedia entry.
Yes, but fusion power plants and their byproducts will be dangerous for less than fifty years after decommissioning, vs thousands of years for fission power plants.
Don't forget that France suffered several islamic terrorist attacks before 11/9/01 including a horrific attack on the Paris metro.
You seem to be reading even more into the BBC article than what wasn't there. It's bad enough that this formerly excellent news organization has become so biased in its "reporting", but even in their article it didn't say that the US was stating the reason was because they were mad at France - it's only the BBC saying that's why the US favors Japan. The article only casually mentions that all the other members of the group prefer Japan over France too.
...And that is why we are likely to be using Deuterium-H3lium3 fusion, as it produces protons and no fast neutrons like D-D fusion.
Protons can be contained by magnetic fields, neutrons can't. That means less rad worries.
... is access to ITER while conducting experiments on neutron capture to produce fissionables, including weapons grade. France is likely to scream bloody murder sooner or later when the US does this (because they can; because they want to world to see them supporting non-weapons based nuclear work; because they want to be seen standing up to the World Bully; because it could encroach on their own high neutron producing commercial reactor business; etc.). While the people of Japan are equally as likely to find displeasure in what amounts to nuclear weapons research being conducted on their soil, the Japanese government and social structure will keep the noise level much lower than would occur in France. The US could get booted from France (it happened to NATO), but not from Japan.
d f). If the US were interested in energy production, rather than neutron production, they could have pursued thorium based fission reactors (http://www.americanscientist.org/template/AssetDe tail/assetid/25710/page/2). They're not as clean as fusion, but cleaner than heavy uranium and plutonium reactors. They're not externally neutron efficient, because they use their neutrons "breeding" thorium 232 into uranium 233, the actual fuel for the reaction. Thorium reactors can be built as neutron sources, but that's hanging a bag on the design; the more efficient designs don't need or incorporate that because they use the neutrons themselves.
Although fusion is relatively "clean", ITER is still a neutron heavy design (http://wsx.lanl.gov/Publications/neut-activate.p
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Fusion is the one technology among a handful of others that will fundametally change the face of the world in the next 20-30 years and the U.S., the last "Superpower", is going to let that technology be developed on foreign soil.
ITER has only survived because of international funding. The US came late in the game.
If you come to the bar when the lights are just being turned on, you don't get to take anyone home.
Long live Schrodinger's cat...
nope, rtfa, japan said it will cover all costs if its built in japan - so no megabuck for them...
really neat idea, but wrong ^^
Basically fusion is not that hard. The problem in a fusion reactor is that the plasma cools off very quickly (seconds). If we let:
EO = energy outflow (cooling of plasma)
EF = energy produced by fusion reaction
EI = energy input (external heating)
then the following equations can be set up:
1) EO 0, the above equations 1 & 2 are hard to maintain. Why? Because hot plasma is cooled down by the reactor walls (+ other kinds of cooling).
Simply put, EO (cooling) is an area dependent function.
EF (energy from fusion) is a volume dependent function.
Thus, if you just build a large enough reactor, you can increase the EF/EO rating as much as you wish. However, a larger reactor costs more.
If we build a big reactor (r=20m) it would produce net energy output. It would NOT be commersially usable.
The ITER or Not-ITER discussion is about whether a large expensive test reactor would be worth its investment, or if the money rather should be used for base reasearch and computer simualtions.
There are two fundamentally different fusion reactors, the "tokamak", and the "stellarator" (IIRC). You want a magnetic field inside the reactor that keeps the plasma away from the walls. In the conseptually easier tokamak, that magnetic field is caused by letting a large (Mega Amp) current flow through the plasma. This current is produced in the plasma using the same concept as a AC voltage-transformer (the plasma is considered one of the spools). However, this means that the current in the "other" spool needs to increase linearly in order to maintain constant plasma current. In reality, this limits the time the reactor can operate to a few seconds (then you lose the plasma and need to restart).
A stellarator uses a very complex set of spools around the reactor to create constant magnetic field inside the reactor. "Very complex" means "not yet practically solved". Actually, its primarily a computational task.
1) EO < EF + EI
2) EO < EF
1) means that we have a net energy output (assuming 100% efficiency)
2) means that we have a "lit", self sustataining reactor
Actually they are outlawing the wearing of any religious aparel and that includes the head scarf (rather than the veil) crucifixes, kipurs and the like. Basically they are saying our schools are secular and so all religious identity is banned. I really don't have a problem with that. People can believe what they like but I don't want it forced on me. The difficulty is that you have to decide whether something is religious or cultural and separate the two.
Tokamak Fusion reactors do not virtually pose any risk. There's no accumulated energy or chain reaction involved...
I don't consider 72% in favor of a "slim majority"...
There plenty of policits to go around. The European Union wants the site to be in France (I wonder why?).
Meanwhile, "Canada, China, Russia, South Korea, the United States and Tokyo itself are reported to be favouring Japan".
It seems like its the EU against the world on this one.
Do some research: the original war with Iraq over the invasion of Kuwait never ended.
The UN agreed to enter into what became a 10+ year-long cease-fire with Iraq. The sole purpose for this cease fire was to (a) allow Iraq to preserve some sense of independence after the defeat in the Gulf war, and (b) allow the UN to verify the absence of WMD programs in Iraq.
Instead of complying with UN resolutions, Saddam Hussein and his government spent over a decade blustering, posturing and doing their best to draw out what could have, and should have, been a very quick conclusion to the Gulf war.
US and coalition forces did not act illegally. They simply cartried out the original mandate they were given by the UN. If that's a crime, then so was the Gulf war, and any other action sanctioned and supported by the UN.
"Great men are not always wise: neither do the aged understand judgement." Job 32:9
I urge slashdotters to read some european history
If it doesn't involve nonsense like orcs, mithril armor and little twerps playing 'witch' games, then no Slashdotter will read it.
I suggest Keegan's "The First World War" to dispell any Merikin foolishness about how cowardly the French are in wars. The US showed up in the Great War well after the shit went down. Also, according to cca 1941 GOP policy, WWII was "Roosevelt's War." Godless unpatriotic queers!
Comparing it to Windows will be a moot point, since El Dorado is going to have a 40% larger code base than XP.
Sorry but ignition has been reached ad fusion sustained for minutes.
I don't think so. If you clicked on the link you would see that ignition in this context refers to the point at which the energy derived from the fusion reactions is enough to maintain the necessary plasma temperature to continue the reaction. Correct me if I'm wrong, but current reactors haven't even reached a breakeven. The energy output from the fusion reactions is less than the energy needed to heat the plasma.
But i am probably a bit eurocentric.r s-hybrides.html).
I think the french spot is good because it is in europe with some quite strong economies that has been affected as badly by the US recession.
It is also quite close(4:00 hours by tgv ) to the high energy physics research center of CERN(http://www.cern.ch) and the nano tech in Grenoble(the reactor group http://isnwww.in2p3.fr/reacteurs-hybrides/reacteu
Interesting thoughts you have there...
Building a stable, sustained, controllable fusion reaction is relatively easy. That isn't, and never has been, the problem. You contain the plasma in a magnetic field that has a single half-twist in it.
Building a stable, sustained, controllable fusion reaction is _incredibly_ difficult. Yes, plasma can be contained by a toroidal magnetic field, FSVO "contained." A nice, cold plasma, at a few tens of thousands of degrees? No problem. At higher temperatures, though, collisions knock lots and lots of ions and electrons off-axis and into the walls of the reactor. This is a major mode of energy loss in magnetic confinement fusion experiments. As you mentioned, instabilities are also a tremendous problem, and that problem has not been solved.
Once you ignite your super-cold plasma, the nuclei are already much closer together, and can't move apart (density too high, plus magnetic field containing the plasma). Your ideal starting material would be a Bose-Einstein Condensate. You cannot get a better density than that, using just conventional means.
This is why you'd need the stupendous magnetic fields. What I'm suggesting is not fusion of a low-density gas, but fusion of a pseudo-liquid or pseudo-solid. To retain that kind of density, when the material is undergoing fusion, would require fields vastly greater than those currently used in fusion research.
As far as Bose-Einstein Condensates go, BEC's occur at temperatures in the nanokelvin range -- that's a full, what, 12 or 13 orders of magnitude too low in thermal energy to overcome the Coulomb potential keeping the nuclei apart. BEC's are notoriously tricky to create; you need to go through several cooling stages involving precisely tuned ultrastable lasers, and at the end of all that work, you get a ball of maybe a few billion atoms. It is simply not feasible to produce BEC's at any larger scale, nor to keep them condensed at fusion temperatures.
And as stupendous magnetic fields go, well, the best anyone can do right now is a sustained field of about 25 Tesla. I don't know offhand what fields they use in Tokamak experiments, but I'm betting it's no more than 10 Tesla, nor less than 1. Either way, there is no way we know of to make steady-state magnetic fields "many orders of magnitude stronger."
It's late now, and I'm getting tired, but suffice it to say that there's a lot more to be done than just making everything bigger. The energy scales are enormous, nobody really knows how to keep a plasma hot and contained, and it's going to take a lot more R&D before we can get usable energy out of fusion.
American economocs: "As long as the total stuff you make exceeds more than everybody else, it doesn't matter that your debts are astronomical."
I don't have time to register for slashdot right now, so I'll hope someone will mod this up so jd can read this.
jd, you are misinformed. Creating a stable plasma field is *very* hard indeed. This has been fusion power's greatest problem for several decades. The torus was a great way to confine the plasma, but we still have problems with instabilities.
Trying to store so much energy in such a small volume is like balancing an elephant on a needle. It is an unstable system. Any kirks or quirks in the plasma and the system crashes.
Another big problem is with neutron bombardment. Only charged particles are confined in the magnetic field. There's nothing to build the reactor of that can sustain this bombardment without becoming radioactive. All proposed materials are extremely poisonous and have a limited lifetime, and one of the reasons we wanted fusion power in the first place is environmental issues.
I still say that ignition has been reached and sustained for several minutes. Of course you're producing (gamma radiation+neutrons)-> heat and heat is termodinamically not very efficient to be converted in electricity.
So, what has not yet been reached is the energetic breakeven point inclusive of all the energy losses.