Slashdot Mirror
Japan's JT-60 Tokamak Sets New Plasma Record
Dipster writes "The Japan Atomic Energy Agency has announced that its JT-60 Tokamak has almost doubled the previous record for sustained plasma production, which is now sits at 28.6 seconds. It is believed that once 400 seconds can be achieved, a sustained nuclear fusion reaction will be possible. While 28.6 seconds is a long way from 400, it raises hopes for what will be possible from the ITER reactor, expected to be finished in 2016."
old
Let's see, 400 seconds - 28.6 seconds .... works out to about 50 years. Still.
Never shake hands with a man you meet in a fertility clinic.
Dude, you gotta change that pentium. ;-)
Common sense is not so common
Yo momma's so old and fat, she sat on top of Mary Wollstonecraft, and she died.
until fusion power can be put into production? I know a lot of advances have been made in the last few years, small scale fusion using pyroelectric crystals and such, but really how far are we from the goal? Can anyone in the know comment?
I know its pretty unreasonable to ask "when is technology x coming out," but a rough order of magnitude (are we talking 10 years? 100?) has got to be doable.
Also, if we do get large scale fusion, is it really going to be cleaner and safer than modern fission plants?
Why?
http://michaelsmith.id.au
as someone who worked in the energy generating business i hope fusion comes sooner rather than later!
the price of oil and gas are going thru the roof, and these two fuels are what keeping the base load plants running here in ireland (and most of the rest of the world with notable exception of france)
theres alot of buzz around wind power nowadays but alot of people dont realise that with average 20% availability (compared to 80-90% of base plants) wind power
just doesnt cut it, and u need to have for every MW generated a backup fossil fuel generator (or pump water storage system) waiting and being ready in case the wind quite literally stops blowing
nuclear fission plants will never be built here either (the greens are quite good at scaremongering)
"...it raises hopes for what will be possible from the ITER reactor, expected to be finished in 2016."
Look at that, it'll be completed in exactly 10 years. Finally, this time 10 years means 10 years.
If you are about to mod me down, keep in mind that this post was most likely sarcastic.
Jeez... If you hafta ask, we certainly aren't going to tell you.
Was I the only one who thought that it was for a 60-inch plasma screen?
"Sure there's porn and piracy on the Web but there's probably a downside too."
Fusion research is one of the only promising research fields whose funding has decreased substantially over the years. In 1970 it was predicted that ITER would be online in 1995, with a demo commercial reactor in 2005. Given that funding was cut once the oil crisis was over, is it reasonable to expect all deadlines to remain the same? In any case, now that construction has started on the ITER site, we are definitively 10 years from an net positive energy balance plasma, following ITER's research, speculated to end in the 2020s, we'll probably have a commercial demo in 2030/40s and large-scale implementation by 2050.
to all you wanting to get more info
ITER is designed to produce approximately 500 MW (500,000,000 watts) of fusion power sustained for up to 500 seconds (compared to JET's peak of 16 MW for less than a second). It is a significant amount of power for a fusion research project; a future fusion power plant would generate about 3000-4000 MW of thermal power. Although ITER will produce net power in the form of heat, the generated heat will not be used to generate any electricity.
http://en.wikipedia.org/wiki/Iter
I wonder what would happen if someone were to crash land a plane in a tokamak..
But it's NUCULAR!!! It's BAAAAAAAAAD!!!
As a bachelor degree student in physics in the 70's and early 80's, fusion research was on of the 'hot' topics. The tokamak was the predominant fusion plant, but other fusion reactors were being investigated. In those days we measured sustained reaction times in milliseconds. Obviously I haven't been keeping up, 'cuz 28 seconds sounds like a lifetime to me now.
-- There are 10 kinds of people in the world, those who understand binary and those who don't.
Oh c'mon this is all just a fun gag. The energy problems were solved long ago. This artificial scarecity is just a tool of manipulation and entertainment. Got the herd all chasing their tails. Of course if I offered any real proof of my claims they'd kill me, just like they did the others.
The greens (and other similar political groups) scaremonger against nuclear because it is (according to them), the greater of all the available evils.
:)
If you want nuclear to succeed, you need to find a greater evil, for example:
"
Scientists have released details of a discovery last month that when a tiny adorable kitten is poked with something pointy and sharp, an incredible amount of energy is released, many many orders of magnitude more energy than the kitten would consume in food during its entire life.
There is much speculation about where the energy comes from, as it clearly violates almost all known 'laws of physics'. It has been determined so far that the more cute and adorable the kitten, the higher the energy output.
But, with the energy crisis worsening, a proof of concept fully-automated-kitten-poking power plant has been set up with the ability to hold 30 cute and adorable baby cats. Even with an initial supply of 10 kittens, being poked 3 times per hour, the energy output is enough to supply a major capital city during peak hours.
Plans are being drawn up to build a plant large enough to supply the whole of Australia.
"
Suddenly nuclear doesn't seem like such a bad option
Have you ever tried to count the neutrons that come off a fusion reaction? If you do you will see that there are so many that the _best_ use of fusion once we get it will be to operate as a breader for U239->Pu239/Pu240 production or th232->U233. These are viable fuel cycles.
The short of it is that fusion is rather dirty - just as bad if not worse than fission and the reason is because of all of those neutrons that are released.
Forget about OIL & GAS dropping in price for any length of time.
Saudi Aramco has announced as of April 2006 that Saudi Arabian oil production is now in terminal decline and this is taken over all the production the country can muster which includes some heavy oils that were frowned upon before. Ghawar in particular is suffering about 8% declines.
Kuwait announced in November of 2005 that they are in terminal decline as well as the Bergan field has gone over the top.
Of the top four this leaves the Pemex (Mexico) Canateral field dropping from about 2 million BOPD currently to under 1.6 before the end of 2007 and China's DaQing feild also dropping by about 6% per year.
The combined reduced production (read depletion) of these 4 fields alone cannot be replaced.
You can say that in Ireland they will _NEVER_ look at fission - and you are completely correct about the problems with wind and solar. However their other option will be to see if they can buy coal and failing that - they will have to start driving their cars less which might mean getting a horse - and figuring out how to superinsluate their houses which is also something that most people seem to be adverse to doing. And even if they do this I suspect they will be importing nuclear power. Perhaps it will be from France mind you via the tunnel.
Ofcourse some methods of saving/generating power deserve more funding then others, I am pretty sure fusion research deserves a lot of funding considering its promise.
Thermal Depolymerization prolly would deserve some funding too, if it helps for the environment. But you'll have a hard time convincing me making oil from plastic/biomass and then burning it is more efficient then just burning it directly. Even if this burning is centralised, you still have to transport the biomass/plastic to a Depolymerization plant, then the oil to where the energy is needed.
It may be very usefull if oil gets expensive and other portable energy technologies(like hydrogen cells) don't work.
Actually they are considering buying a nuclear powerplant in Wales and bringing in the energy using an interconnector.
Alot of electricity here is generated by peat and coal, with a third of a billion euro being spend on installing scrubbers and other "cleaner" coal technology down at moneypoint on the shannon. What alot of people dont realise is that coal is radioactive and when burned releases dozens of particles (some are toxic or/and heavy metals)
unfortunately ireland with its clean green image world wide in reality is one of the most oil dependant countries in Europe
also we completely screwed up on the meeting Kyoto targets (emmissions actually went up!) thanks to the energy hungry Celtic Tiger
there my 2 eurocents
The actual research itself is relatively unpredictable, I understand that. But when I read that completion of the ITER (the way I see it a relatively straightforward job, I assume the blueprints are already completed) is still 10 years away, I wonder how much time could be shaved off that estimate, as well as the ~2050 estimate, if (a lot) more money were put into fusion research.
If nuclear fusion has the potential to provide a clean, efficient, lasting energy source, and thereby eventually solve the energy crises, it would seem to me that investing a far larger amount of money than is being put into it today would be a very good investment if that could mean nuclear fusion can be used a few years earlier. I think ITER's cost is estimated at about EUR 10 billion, which is a lot of money, but in the grand scheme of things (I think the world GDP is somewhere around 50 trillion) it's tiny. And seeing the large potential for creating armed conflict there is in energy shortages even these days, I'd say getting fusion sooner rather than later may very well be a real matter of life and death.
However, when I hear discussions on the energy crises, the efficiency of solar/wind/water power, whether more nuclear fission reactors should be built, fusion isn't even mentioned, let alone considered by politicians for larger investments. Is it simply because it's so far away, and that for the most of us, only our descendants would benefit from those investments?
Once again this is a serious question, I'm no expert in any of this so I honestly don't know.
Until the chubby-fingered children of science-- clapping their hands delightedly at shiny objects-- can find a balancing "bad" for all the "good" they project from fusion power they just cannot have it. Not in this universe. There is no perpetual motion energy source. Thus, the target date will continue to recede.
For the vast order we create by the burning of fossil fuels we pay with greenhouse gases and pollution. There is also the uncounted number of BTUs created by millions of barrels of oil burned every day in the world--not to mention those from wood and coal burning. Where is the balancing "bad" for fusion energy? Where is the price we pay for our "clean" power? NO ENERGY SOURCE IS FREE. Get real.
E Proelio Veritas.
As far as I can read, it seems rather impressive. Their record for plama duration is... 390s ! More information on the fusion-dedicated French CEA (Commissariat à l'Energie Atomique) site (in English).
But the question is honest: what have achieved the Japanese? Is their plasma self-sustaining? Have they reached break-even point and maintained it during the whole 28.6 seconds?
Anyway, just give a look to the CEA site: from pictures to videos, plenty to discover there.
I am not Remy Mouton, unfortunately: http://remy.mouton.free.fr/art/
Suddenly nuclear doesn't seem like such a bad option :)
Pfft. You're talking to geeks here.
If there was a device that minced 3 kittens an hour and gave you an extra 5 fps in quake, we'd be all over it.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
But, progress is being made, maybe the rate of progress is a lot slower than anticipated. But it's clear physicists are getting closer and closer. The public needs to be patient and not cut off funding. Just because the 50 year prediction was wrong doesnt mean that this is a fundamentally impossible acheivement, as we can see, progress is being made.
My main concern is the current environmentalist movement which doesnt want humans have a decent quality of life with cheap access to energy. They are stuck on what they think is pollution free energy production methods such as solar (solar cell production is not eco friendly), wind (motor magnets & airfoil manufacture not necessarily pollution free, ugly, noisy, bird killing, proven to effect natural weather) and ethanol (combustion still produces pollutants including carcinogens, large scale production monopolizes vast areas of arable land).
So, even though at least one of the co-founders of greenpeace is in favor of nuclear power. Greenpeace and other "environmentalist" movements have gotten so hateful of the nuclear industry that they have apparently lost all rationality when it comes to examining the benefits of fusion.
And so it seems that many modern environmentalists don't care enough about the environment to be rational in trying to protect it. Let's not forget that most humans are environmentalists, who wants to live in pollution? The entrenched environmental lobby is actively blocking any workable ideas in reducing pollution and improving quality of life.
Double the research.
We could have nuclear fusion power now, we could have had it decades ago, were it not for political concerns. Consider this:
Such a setup should generate more fusion power than we'll ever need.
But of course you'd have to manufacture fusion bombs at a rate of one every five seconds. If a country were to develop that kind of manufacturing capability, it would be very easy to divert some of those bombs for weapons use.
It's just a scam - they are really working on zero point energy :)
Will the be able to keep it open^H^H^H^H powered on for more than 38 minutes?
"If there was a device that minced 3 kittens an hour we'd be all over it."
fixed that for ya.
Just so we get a balanced point of view, here is a nice timeline on Cold Fusion. Evidently, it is real, and something these billion dollar Tokamak heat sinks don't want to see or believe as their funding could suddenly change.
Anyway here is the link for your perusal.
Mind | Body | Spirit | Cash
Call me ignorant, but what's the Irish objection to nuclear power?
I don't get it. You'd think the Greens would be all over nuclear (fission) power. It's clean, and the only problems with it are ones that can be solved: meltdown and the production of waste are both manageable, and with a little effort and ingenuity. The risk of meltdown has basically been solved by new reactor designs, as I understand it.
The problems in coal and oil power are not solvable, namely the CO2 emission and the fact that we're going to run out of the stuff. It's feasible that with scrubbers and new technology it might be possible to reduce other emissions to manageable levels, but there's really not much that can be done with all that CO2. (Proposals like "stick it under the ocean" that I've heard floated don't seem practical.)
Hydro's tapped out, we're still waiting on the promised wind farms to be set up, etc. Nuclear power is proven to work; why don't we use it? It's not because I'm unconcerned about the environment that I advocate it; it's because I *am* concerned.
This is what passes for insightful on slashdot these days?
If you don't know where you are going, you will wind up somewhere else.
Man, you'd think people capable of 390s would be capable of a decent webpage. Course, they are French.
;)
:)
-
Yeah, at least I warned ya
All AC should start out -5
Efficient. Reliable. Decentralized. Pick any two.
If you don't know where you are going, you will wind up somewhere else.
http://en.wikipedia.org/wiki/Aneutronic_fusion
I will quote one of the most relevant parts:
This is the from the article on aneutronic fusion, even. D + D fusion is much dirtier.
I predict that we will have fusion power not before oil reserves are exhausted - too much money/politics/everything involved. Can't be allowed. If we have fusion power production tomorrow - what would all those arabs do? Huh?
What a day to be without mod points.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
It comes in the form of hard radiation and lingering radioactive by-products, you whiny twat. If they thought fusion was just "do-able" they'd be setting off hydrogen bombs to harness tidal motion in the ocean. Instead, for our sake, educate yourself on WHAT THE RECOGNIZED PROBLEMS ARE.
t ant_fusion_reactions
http://en.wikipedia.org/wiki/Fusion_power
http://en.wikipedia.org/wiki/Nuclear_fusion#Impor
Please come back when you have something better to offer than "NO ENERGY SOURCE IS FREE".
What the earth would look like with tens of thousands of mini-suns burning on it's surface? Energy pollution :/
"I don't know that atheists should be considered citizens, nor should they be considered patriots." George HW Bush
Again, modern technology should be considered before weighing the "risk of meltdown".
http://en.wikipedia.org/wiki/Pebble-bed_reactor
http://en.wikipedia.org/wiki/CANDU_reactor
I especially favor CANDU myself, between the use of unenriched uranium (or thorium), and that any significant deformation of the fuel geometry results in an inability to sustain a chain reaction
I'm not so sure that hydro is tapped out. They've started to talk about a tidal barge across the Severn Estuary again. If this got past the conservationists it would supply 25% of the current UK power demand. Not a single city, but the whole country. Of course it will never get built until there is £50B lying around that the government can claim, and all of the local residents / environmentalists have died. The irony is that not building it is contributing to the destruction of those habitats anyway.
Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
There is. It only requires that the geeks masturbate 3 times an hour. God will take care of the rest.
n/t
The big win with fusion will require a major theoretical breakthrough rather than simply carrying the current plans to their logical conclusion.
Read up on the LTX device proposal, and the related journal articles which have been written about the theoretical advantages of a low recycling limiting surface such as lithium, specifically liquid lithium. LTX is "small" plasma device which will be examining the plasma physics issues of low recycling. Even though the LTX device itself won't be a fusion reactor, the physics of low recycling walls could have a huge effect on the type of plasma density and temperature profiles achievable in reactors, and thats a huge deal when it comes to the physics of steady-state operation, as well as the engineering issues of efficiency and cost. A low wall-recycling condition its extremely difficult to achieve for magnetic confined fusion devices, and its basically an unexplored piece of the reactor parameter space.
The best TFTR results used thin solid lithium coatings to achieve the best ever energy confinement for the device, and the same experiments showed a decrease in wall recycling. Modest recycling reduction was observed, down to about 80% at the wall, in those TFTR experiments, and there was a definite correlation between turbulent transport suppression and the effect of the solid lithium coatings on recycling.
LTX on the other hand is going to be using liquid lithium coatings over the entire plasma limiting surface, and the liquid lithium has distinct advantages over solid coatings when it comes to the details of the surface chemistry involved in recycling. Solid lithium will form surface coatings(oxides and hydroxides) which degrade lithium's ability to getter hydrogenic species. The liquid lithium doesn't form these surface coatings and the chemistry is more dependent on volume effects instead of surface effects. LTX is small, but it might be able to reach the theoretical limits of recycling ~ 10%, and will explore a whole new regime of plasma transport. Based on the current theoretical understanding of how extremely low recycling walls affects energy and particle transport there is even a mock-up design for a reactor-sized device which incorporates liquid lithium walls being poked at by people who do numerical simulations for a living.
If you happen to be going to the Plasma Surface Interactions conference in China at the end of May, you may be most interested in taking a look at the posters/papers concerning low-recycling.
PSI Conference Website http://202.127.205.20/
Abstracts P2-41 and P1-70
While a fairly obvious flamebait and off-topic to boot, I find it interesting that, while accusing Mandrake of racial segregation, preventing people from using ebonics versions of their OS, and saying that contractions for fairly-obvious commands are, in fact, racist acronyms, they then proclaim a stereotype for its cause.
Ninjas and pirates. How piquant.
If you want a greater evil, it's coal. It's by far the most widely used fuel for electrical generation in the US, and it's more evil than poking kittens. Coal can almost be considered a default choice for electricity because it's cheap, plentiful, and most environmental costs are externalized.
First off, the spherical chamber: Do what Operation Plowshare did, use a nuke to build the chamber by detonating it underground. I bet that if you mined ventilation shafts at the near "edge" of the explosion, you could vent off the overpressure. The heat from the explosion would sinter the rock together. All that would be left would be to send in some remote-controlled mining equipment to "smooth" it out. You aren't talking a big sphere here, probably well less than a mile in diameter, but that is OK.
Clean out/rebuild the overpressure ventilation shafts - you will need these later.
Attach to the inside surface of the chamber many, many thousands of feet of stainless steel piping/tubing - probably 6 to 8 inches in diameter, if not larger (I am not an engineer, can you tell?). This is your "energy collector". You will run water through this.
Spray the inside of the sphere (over the top of the SS water piping) with a bunch of concrete - maybe further steel reinforce it, perhaps make an agregate with granite or something. This layer should probably be a few feet thick, probably thicker.
Now, you simply do the same thing - dropping the nukes so they explode at the center (or near). The overpressure goes out the vents (this is a "fatal flaw" - I don't know what you do with the escaping radioactive material and/or radiation from these vents). The heat heats the water in the coils, which is then used like a typical fission reactor by passing it through a heat exchanger system. The coils are buried in the concrete/granite aggregate, which holds the heat very well, so the "every 5 seconds" could probably be extended to something longer once the system is up and running (the first few "primer" explosions would have to be done in more rapid succession since they serve to heat the system up to working temperature, but later blasts can be spaced apart more as the system runs).
Now, for the hydrogen devices - you don't need the "high yield" devices used for weapons. You grab another of the Plowshare-related systems: the delivery and propulsion system from the Orion. These thermonuclear devices were designed to be about the size of a basketball, to propel a ship through space, detonated behind the ship (with an ablative pusher plate to propel it, riding the shockwave). They were extremely small fusion devices - which got them immediately sucked into the "top secret" drawer of things, of course - but they had much lower yields, and if set up properly, the explosion from them could be sized slightly smaller than the size of your sphere, so you harvest the heat, and not anything else that would possibly destroy the system in short order.
In theory, aside from the radioactivity being released, plus possibly servicing/refurbishing the system (as the concrete/granite aggregate layer ablates) - this should work. Unfortunately, even if all of that was conquered, I am not sure it would be any more efficient than a regular fission reactor, plus there is likely no way the design for those mini-hydrogen devices will ever see the light of day again outside of WW-3...
Reason is the Path to God - Anon
India has proposed a combined hybrid fission/fusion reactor as have many others. The funding for India's new SST-1 http://www.ipr.res.in/sst1/SST-1.html superconducting tokamak was secured under this pretext.
If the article were correct, and the "best that we can hope for without massive shielding" scales as stated, why don't astronauts all quickly die? Neutron flux should scale the same as anything else (1/r2), and they sure don't have massive shielding on the ISS. So if we were to build a "little sun", someone standing at a point from which the energy per square meter was the same as that from the sun in LEO, they should need no more protection than someone on the ISS, which should be cheap and easy to provide since we don't have to hoist it up there. Yet this "little sun" would be providing a considerable amount of energy.
Let's do some order-of-magnitude estimates. If we call the solar equivalent distance r, we should get 10 Watts/meter * 4*Pi*r2 watts out of it, or about 100*r2 watts; for the 100 MW reactor, this means r is about 1km. If our containment wall is at 100m, we'll only need one thousand times the shielding of the ISS; in other words, in the worst case we should be fine if we bury it about 20 meters down.
Also, for comparison, how close could you stand to the furnace of a 100Mw coal fired plant if there were no shielding? I think 110m would be rather...uncomfortable, and your life expectancy wouldn't be much better than that cited in the article.
--MarkusQ
I'm sure since this is /., all of you have tried the match/fire/etc in the microwave trick which generates what can only be described as plamsa balls that fly around inside. One trick that I found online was to place an inverted glass bowl over the candle which contains the plasma. I've done this and sustained the plasma for way more than 30 seconds. Of course, it melted the glass and created some micro-stress fractures which eventually caused the bowl to shatter once it cooled enough. (much to my wife's chagrin) But what am I missing here... If I can make that much for so long in a simple microwave using a match, shouldn't we be able to get the 400 seconds one to work as well? Maybe its the containment issue since my glassware wasn't up to the task. Of course, this would be a carbon plasma, right? I don't know how to do deuterium in a microwave... I do know that the amount of light/heat that a single plasma ball gives off is really a lot. Anybody ever done any serious experiments with this?
Fusion power has been 20 years away now for quite a few decades.
Call me when they can sustain it for 28 minutes, instead of 28 seconds.
Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo! http://goo.gl/J9bkO
All this research just to enable more heat transfer turbine made eletricity.
Why is there no research to harvest the energy of these reactions directly. I really hope that this is just the bronze age of eletrical generation.
There is another place that hasn't used all of its energy -the past. All we need to do is develop a way to acquire this vast resource through temporal wormholes and we'll have all the energy we need today. That is, until those self-serving asshats in the future come up with the same idea...
Does anyone remember a short science fiction story that basically had that as a premise? I can't remember what it was called or who it was by, but the idea was that a civilization built a generator that provided wireless power distribution throughout not only all three dimensions, but forward into the fourth as well. So basically as soon as it was turned on, you'd have power for the rest of eternity, even if you shut it down.
The story used this as a device to show how easily people "forget the development," -- once people take something for granted, they forget how it works and how (or even if) it was built.
I remember really liking it, but I can't think of the author or title.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
The previous record of approximately 13 seconds, set by the Large Helical Device (also Japanese), was accomplished at 60% breakeven.
What was the peak and integrated efficiency of this 26 second run?
Simple Machines in Higher Dimensions
Checking a couple of journals reveals that the JT-60 discharge duration can be as long as ~65 seconds while the ELMy H-mode, which ITER will operate in, lasted for about 30 seconds. The article might be referring to this or it may be referring to some of the 30 s discharges that JT-60U has, I'm not sure. Something else that is interesting is that there are plans to further upgrade JT-60U (U is for upgrade from JT-60) to JT-60SC which will include superconducting magnetic field coils. I haven't been able to find a timeline, but I do know that the design for it is complete.
come on already. we have been hearing tantalizing bits of data about fusion and tokamaks for YEARS AND YEARS now. When are ya gonna figure it out already?? ;)
(i'm mostly being facetious, i know it's a so-called "hard problem"... but you guys really have some beers waiting for you if you figure this plasma fusion thing out and get positive net energy flow...)
Everytime I read any Fusion based posts it really allows me to see how ignorant a LOT of people are. Some seem pretty close, but get caught out as being bulls-hitters somewhere in their post
K, I am doing a PhD in Fusion in one of the best fusion plasma groups in the world. I would be happy to answer any questions.
Not having a go at any random posts, but just a few mistakes I didn't see get checked. 1. Yes Fusion is safe, very safe, super safe. Safe!! You can ask me why, but no-one ever seems to pay attention, or even understand.
2. Fusion weapons have been around since at least the 1960's! Hydrogen bombs. Kinda like 50 years too late to be scared about that one.
3. Would you like to know why fusion isn't here yet? It's very difficult! It's not an oil conspiracy!! The people in fusion are academics and believe me when I say they don't generally give a crap about money. They are smart people concerned with the environment.
4. Why is it difficult? You can't switch JET or MAST on for too long because of Ohmic heating. It basically implies that super conducting (very $$$!) coils are needed to get around this problem. ITER will be one of the first reactors to have all superconducting coils.
6. Anything else? Yes, actually. We are literally making it up as we go along. How many people know exactly what a plasma is? I mean what defines it? It's Debeye length? Collisionless? Quasi-neutrality? What do any of these terms mean? If you don't know you probably aren't qualified to talk on fusion. Plasma physics is relatively to the rest of science an incredibly new and young field and it is extremely varied.
There's lots and lots going on in fusion. I apologise for the lack of links but i'm typing quickly and don't have time. Suffice to say, everyone in the fusion community is very enthusiastic about it. It is getting more and more (international) money all the time. The Chinese and Japanese are involved, not to mention India and the most of the West.
On an interesting side note. The thing that mainly held fusion back was
can you guess?
AMERICA!! Constantly pulling in and out of the project. However, now that the Indians are involved the funding is about 110% of what is required. So if the yanks pull out again then they will fall behind because no-one else cares anymore and we'll have enough money to, and we will, continue.
I agree, and I wasn't implying that the 'fear' of nuclear is rational.
But, the thing about nuclear is the potential for big accidents. The effects of a nuclear accident can be around for centuries.
There are nuclear reactor designs around now that are 'passively safe', where if something goes wrong, the design is such that it automatically slows down (eg instead of the nuclear reaction getting faster with heat, it gets slower). Many of the historic concerns for getting energy by splitting atoms are no longer valid.
"While 28.6 seconds is a long way from 400, it raises hopes for what will be possible from the ITER reactor, expected to be finished in 2016."
Hasn't "a workable fusion reactor" always been a decade away since at least the late 70's?
--MAB
I call FUD. It's radioactivity is beta rays, and weak ones at that. They put the stuff on keychains, in watches and gun sights. Your smoke detector is a bigger danger.
I guess a device that requires funding and the best scientists from all over Europe, U.S., and India is not going to some rogue state or into some terrorist camp. On the other hand, the big sticking point for fission power is plutonium and proliferation, and a fusion reactor would be one powerful source of neutrons. If a working fusion reactor is developed, are you going to say Country A is allowed to have one but Country B is not because they are going to sneak bomb-making into it?
Maybe the fusion neutrons are of the wrong energy for breeding plutonium or other bomb elements?
Centralizing something makes the plant more efficient because it produces in higher volume (greater economies of scale). If the economies of scale aren't sufficient to overcome the transport losses, they wouldn't centralize things. Right now a power plant may require a dozen operating staff, but the hundred substations around the city are unstaffed. If you made each substation its own generating plant, you would need a hundreds of operating staff members. You might waste less energy (assuming the smaller generators were as efficient as the huge ones), but the added cost of labor would outweigh the savings.
Also, hydrogen (i.e. protons) can be a byproduct of nuclear reactions, so hydrogen may be viable energy source rather than a storage medium.
dom
Maybe if we got the Iranians interested, they could get Nuclear Fusion up and running in a couple of years? They've been making some good progress with fission!
Zen tips: Pay attention. Don't take it personally. Believe nothing.
I hear that there is enough duterium in sea water to provide enough for (essentially) ever, what about the tritium source ?
This is important: power has to be at an affordable cost.
Efficient. Reliable. Decentralized. Pick any two.
<voice class="text/wayne">A fission says what?</voice>
StoneCypher is Full of BS
Solar in Ireland???
I have been to Ireland in the spring. I couldn't get enough solar gain to keep me warm much less generate any power!
Even Fusion would have some issues for Ireland. I don't think they have any local source of Uranium so they would still be importing all their power.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Well, as long as you are so amused... Care to link me to any information regarding the breakeven point and why it can only be surpassed for a short period of time? I can't seem to google my way to that info. Wikipedia did seem to indicate that fusion power is not the holy grail of energy production that the masses seem to think it is... /was a physics major for a semester or 2 at Cornell //couldn't take the calculus torture
The real problem with 3kph (kittens per hour) is that we dont clean, and thats gona be whole lota stink...
and just wait till the 50kph model comes out...
The neutrons produced by DT fusion are an issue, but they don't have to be a long-term one.
You want as many of the neutrons as possible to end up in the lithium blanket, where they will breed more tritium
for you (half-life 12 years, so surplus tritium can be got rid of easily enough, making valuable helium-3 in the process).
Some inevitably end up hitting the structure of your reactor, and much work is going into choosing materials that will
either not absorb them or produce something with a short half-life (to stability) and decent structural strength. This irradiated wall material is basically the only radioactive wsste from a fusion reactor, and people are pretty confident it will just need to stored for a few decades before being safe again.
Thank you. Somehow I'd managed to miss that paragraph. That moves it from the realm of "Now wait a minute!" to "How odd!"
I still have questions about the details/accuracy of their estimation, but that means I'm far better off than before your post, when it hadn't even occurred to me think about the issue.
--MarkusQ
Fusion power isn't free if the cost is Dr. Octopus.
The Sun uses different fusion cycles from those in human constructed fusion reactors.
Those reactions have far too low a cross section to be practical for power generation, and work because of the inertial gravitational confinement because the Sun is enormously times more massive than the Earth.
One thing about weapons proliferation that is not discussed:
Fusion reactors will produce substantial quantities tritium in their blankets from the neutron flux.
This also means that they would be able to breed plutonium from non-enriched or depleted uranium.
Think how tritium production and plutonium production can be mutually substituted in nuclear (fission) reactors today.
I don't know about the exact numbers and reactions but a fusion reactor capable of commercially useful output (i.e. hundreds of megawatts to gigawatts of electrical power) seems like it would be quite capable for making both parts of the special nuclear materials necessary for compact nuclear weapons, i.e. plutonium and tritium.
CANDU reactors are available for sale pending approval from AECL (Atomic Energy of Canada Limited), they can use natural, unenriched uranium, and make extremely efficient use of the fuel burned. They also generate tritium and can be used to breed uranium from thorium. Given the difficulty in mastering the timing required for implosion fission (a requirement of which is also plutonium), proliferation concerns from the creation of uranium would be mostly focused on preventing gun-type (damned simple, monkey-with-a-hammer) bombs from being built, or dirty bombs.
Now, this is not to say that concern and forethought should not be invested in the fusion-proliferation problem, but fusion is hard. It's going to be hard 10 years from now, and when they get it working it's still going to be hard. Right now, we have the next most viable step looking to be the ITER, which is (supposed to be) a joint international effort. The ITER is not going to be run by one country, and I personally doubt that countries like North Korea (current mindset) will ever muster the resources to build viable fusion reactors. I doubt they will ever muster the resources, with or without the Americans opposition.
Commercial fusion power will be like any other tool of useful potency: It will be harness-able for constructive or destructive purposes. And considering how much simpler it is to buy or build a fission reactor today than it is to even plan what the next "leap" in fusion technology advancement will be, I do not currently view proliferation as my top-most concern regarding fusion.
oh man.
;) as that's how I pictured it in my head.
;)
Elbowing doesn't carry well over the Internet, and I keep forgetting that. People always seem to interpret things in the more hostile way, perhaps because people are critical of themselves (this would include me). If you can imagine me being a nice jovial fellow (which I am told I am, take my word for it for now), elbowing you in the ribs with a smirk and a subtle change of voice (think: car salesman) as I say "hey, smart guy! please break it down for me", perhaps you would have received the message better
I appreciate your thoughtful (earlier) reply and I did go ahead and follow the links, but as you mentioned, it gets a little complicated for the "outside" layperson (even after having taken some college physics). I thank you again for your information and I apologize for any misunderstanding- don't be so hard on yourself
Oh. It seems I've overreacted. My apologies as well.
The reason we can only break even for a short period of time is that we're desperately fighting plasma instability. This is the fundamental reason you see so many different shapes for confined fusion devices: we're looking for a way to keep the instability in check.
Consider the case of a balloon filled with smoke. (I use smoke as an example because it's visible and we've all seen its behavior at a variety of temperatures.) When the gas is hotter, it disperses faster, and it moves in more complex patterns; we've all seen that. It's a visible expression of brownian motion; heat is the whacking together of atoms, and there's a fair amount of heat in one of them thar fusion type devices.
The thing people tend to forget about brownian motion is that pressure isn't actually even. When you're dealing with stuff in the tens of millions of degrees, local fluctuations come often and are big. In a lot of ways it's like mean time between failures: there are a lot of small events going on, and every so often enough of them cluster together to cause a fault.
MTBF is actually a convenient analogy here in another way: most computer people understand areal density and its effect on reliability. Or, less cryptically, the smaller you make it, the harder it is to keep it under control. Especially with regards to thermal noise, this is one of current-gen storage's big battlegrounds right now: we're getting to the point where random thermal stress is enough to flip bits, and we're having to break out the bag of tricks to fight that off. The smaller the bit, the more the storage, therefore the better the drive, and so there's this window that's constantly moving: we get a better way to keep the bit stable, we move the crystal size down, we keep our stability window and get better space capacities.
The issue with fusion systems is very similar. The bulk of the reason that most fusion systems aren't break-even is that they put a tremendous amount of energy into two things that the sun gets for free by virtue of gravity: compression of the fuel and temperature (as a result of the brownian motion which is itself a result of the pressure.) I seperate the two because we don't use pressure to generate the temperature; we use current directly applied to the fuel (think neon bulb, then crank it up by a few hundred billion) and sharks. Sharks with frickin' lasers on their heads. Granted the laser is the important part, but it's evil science tradition, and by the way, muhuhahaha.
So, what we're doing is a process race not terribly unlike the hard drive areal density race. What we want is to crank the pressure up, because once it gets high enough, we can get rid of either the electrical current or the laser. Eventually, we could even get rid of both. Magnetic pressure is a much more energy efficient method of heating at that scale; it's just kinda hard to make magnets like that. Kinda hard like we don't really know how to beat what we've got today, not it's just too expensive. Magnet quality is a frontier for fusion in the way that thermal resistance is a frontier for hard drives.
So why can't we run them longer than two minutes? Hell, we can, without problems. But it costs more energy to do so. What we're doing is moving up the bar of pressure, which lowers the energy input. The big deal about TORA SUPRA wasn't that it ran for two minutes; we can run a stellarator indefinately, if someone wants to pay for the juice. The big deal about TORA SUPRA was that it was stable for two minutes with as low an input level as it was, because it relied more on the magnets than its predecessors had. ITER is going to be further down that scale.
The issue isn't the time. It's the time at a given input voltage, and since input voltage is rarely reported on, the media gives a very distorted view of what's actually going on inside yon ivory tower.
StoneCypher is Full of BS
Bar. Pressure. That's a joke, son, y'missed it.
StoneCypher is Full of BS
Thanks for the additional info, I feel like I have a clue about what the issues involve now! The instability issues remind me of chaos theory (i read james gleick's book once). If you are involved with that process, best of luck...
Nah. I write Nintendo games for a living.
StoneCypher is Full of BS