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Z Machine Advances Fusion Race
Journal written by 1ione1 (207861) and posted by
kdawson
on Thu Apr 26, 2007 09:01 AM
from the collaborating-with-Siberians dept.
from the collaborating-with-Siberians dept.
Sandia Labs has announced a new milestone in Linear Transformer Driver technology that aims to solve one of the biggest obstacles to practical fusion reactors. Getting the current needed to "spark" a burst of fusion is doable; getting a constant series of sparks going to create a continuous chain of fusion bursts has never been achieved. The LTD, which allows the Sandia Z machine to fire once every 10.2 seconds, makes it look achievable. The press release (which has been picked up in a few places, but with no further analysis) says that practical fusion power could now be 20 years off.
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20 years off? (Score:5, Funny)
Re:20 years off? (Score:5, Informative)
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Re:20 years off? (Score:5, Funny)
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Good developpers never commit on dates.
Re: (Score:3, Informative)
According to Bussard [google.com], practical fusion power is nearly as available as the money we decide to put into his system. He specifically says in the video that "the physics is done" --which means that only engineering problems remain.
Re:20 years off? (Score:5, Funny)
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Re: (Score:3, Insightful)
Yeah. I came here to make the same quip.
Then I realized a possible explanation. Perhaps every time another milestone is passed, the new understanding moves us closer to fusion and thus on to the next unexpected hurdle. Sort of like being able to see the second mountain that was previously obscured by the first.
Or maybe it's just researchers looking to grab headlines in order to obtain more funding. Either way. :)
Millions of Dollars Away (Score:2, Interesting)
Ask Slick Willie & Friends (Score:5, Informative)
Fuck "in God we Trust," we should just print "don't rock the boat" on our money.
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20 years! (Score:2, Funny)
20 years off? (Score:3, Insightful)
I think that I'll stand by my idea that even if/when we crack fusion enough to be able to build a fusion power plant it'll have to be so big to be worth it, that they won't be able to get the funding to do so.
Basically, Containment costs go up by the square, while energy release goes up by the cube. To make it worth it, we might be looking at a 100 gigawatt reactor*, of which half goes towards sustaining the reaction.
*1-2 gigawatts is a pretty big reactor today.
Re:20 years off? (Score:5, Funny)
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Re:20 years off? (Score:5, Informative)
So jigawatts was a correct pronunciation of the g, but not of the i.
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Re:20 years off? (Score:4, Informative)
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Depends on what you mean by containment (Score:3, Insightful)
--
Mr. Fusion on your roof: http://mdsolar.blogspot.com/2007/01/slashdot-user s -selling-solar.html [blogspot.com]
Re: (Score:3, Informative)
Table top fusion is useful sure but not for producing energy so I don't see how it's related to the current subject.
Re: (Score:2)
Depends on operating costs for a Fusion reactor... if the upfront cost can be paid back in another 20 years and operating expenses do not eat up more than half the revenue.. it will do well. If operating costs/upgrades/maintenance/etc. do eat up the major
Re:20 years off? (Score:4, Informative)
From my understanding of the problems, that'd require a HUGE plant. Right now they're talking about building the largest fusion test reactor yet. One telling thing about the design: It's as large as a modern gigawatt nuke/coal plant, yet has absolutely no provisions for making power from the reactions.
Now, I admit that my figures are estimates, based roughly on the idea that contaiment can be roughly approximated as surface area, while fusion mass is volume based. Thus, square vs. cube.
Take the test plant*, it's as large as a gigawatt reactor. Since they aren't putting any means to generate electricity in, they're obviously not planning on it producing enough power to even offset the cost of the generating equipment. IE not enough power for it's containment costs.
Now, lets pretend that we had many issues solved and could merely double the size of it**. 4 times the containment energy cost, 8 times the power produced. If we have a self-sustaining plant, where enough power is generated for it to continue operating with no external power, the doubling would give us 4X the original capacity available to sell.
Still, even if the first doubling made it self-sufficient, and the second one to produce usefull amounts of power, we're talking about a plant with 16 times the footprint of a gigawatt nuclear plant, half it's power goes to maintaining the reaction systems, and we haven't even gotten to the area need for the steam systems. Call it 20 times the footprint of a gigawatt plant.
We have a huge way to go on efficiency before it'll be practical. This may help, but I still see fusion plants as a long way away.
*last I'd heard, they're fighting over which country to build it in.
**I'm talking about the reaction area size itself. Due to inefficiencies, the rest of the equipment will likely more than double in size.
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And if my grandmother had wheels, she'd be a wagon (Score:4, Funny)
Twenty years off what? And are they light years or dog years?
Re: (Score:2)
Is it when the original article was written, when it was linked from slashdot, is it when I type this post, when I click the submit button, when the site stores it in it's database, when you're reading it. And is it "now" in our dimension or in some parallel dimension?
Re:And if my grandmother had wheels, she'd be a wa (Score:5, Funny)
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In Siberia... (Score:2, Funny)
Z-Machine? (Score:5, Funny)
A stunted oak tree shades the inland road.
Re:Z-Machine? (Score:5, Informative)
Some harsh moderators we have here.
For those who don't know or remember, the Z-machine [wikipedia.org] was the virtual machine environment used to develop the famous Infocom [wikipedia.org] interactive fiction titles, such as Zork and its sequels. Incidentally it was also the first thing that sprang to my mind when reading the title.
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Re:Z-Machine? (Score:5, Funny)
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Re:Z-Machine? (Score:5, Funny)
> turn off light
It is very dark. You are now likelier to eat a grue.
> eat grue
You hungrily devour the grue. You suddenly feel as if you are in Soviet Russia.
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20 year off == 20 good funding years (Score:5, Insightful)
That twenty years (here and decades ago) assumes that governments won't pull funding for fusion research. But they did, and will again. ITER could have been built years ago. It wasn't a lack technology holding it back, it was a lack of money. So don't blame the scientists who give those 20 year estimates, blame your governments.
Re: (Score:3, Interesting)
So all the countries of the world that's economically hogtied to the Middle East doesn't like the idea of vast, cheap energy sources. Right... From what I've understood, getting it started is only a very tiny part of the problem, the biggest problem is "Here's the particles that'll fly out of a fusion reactor. Make electricity out of it". If there really was a clear consensus that it'd be a godsend if we just got it started, it'd have happe
Re:20 year off == 20 good funding years (Score:5, Informative)
They do have a plan for that. A blanket around the reactor containing lithium will both capture heat and breed tritium that's needed for the fusion reaction. One big problem for commercial generation though is the logistical bottleneck of producing enough tritium. Just ITER will use a significant fraction of the world's supply of tritium. The lithium blanket will breed enough tritium for itself and maybe to seed another reactor.
http://www-fusion-magnetique.cea.fr/gb/cea/next/c
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Re:20 year off == 20 good funding years (Score:4, Interesting)
But...
If you think Plutonium is a weapon proliferation problem you haven't seen nothing yet. Tritium is the key to making really powerful small nuclear weapons. Buy injecting Tritium gas into the core of a nuclear bomb you can boost the yield a lot.
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Do we need such "estimates"? (Score:3, Insightful)
Re:Do we need such "estimates"? (Score:5, Insightful)
5 years to design it into a power plant, find and obtain a site, necessary permits, etc... Then 5 years to actually build the thing.
I'll believe that it's twenty years away when we have a working plant sustaining a fusion reaction for testing purposes. IE operating the thing for days/weeks, not seconds/minutes.
We had [umr.edu] the first nuclear pile in 1942. The first nuclear reactor to produce electricity came online in 1951. It wasn't until 1957 when the first commercial fission plant came online. 15 years from the first pile until a commercial plant. All signs point towards fusion being bigger and more difficult, so I figure one will take even longer to build than a fission plant.
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Teller's Classical Super and the tritium problem (Score:5, Informative)
The original hydrogen bomb was known as the "Super" before it was called a hydrogen bomb, and the idea is what every wide-eyed geek in elementary school imagines the H-bomb to be -- put an A-bomb next to a vat of deuterium, and the A-bomb blasts the deuterium hot enough to make it fuse.
As the dudes as Los Alamos started building computers to do numerical models of fluids and radiation and everything, it became apparent that Teller's Super was a dud. The physics of radiation were such that simply sticking a fission bomb next to a pile of heavy hydrogen was simply not going to do anything. What if you sweetened the deuterium with tritium -- then what? As it turned out, you would need gobs of tritium, so the whole thing was a non-starter.
As it turns out, Stanislaw Ulam came up with the idea of a staged atom bomb -- a small atom bomb would provide the shock to compress a big freepin pile of plutonium to make a big honkin atom bomb, and Teller got ahold of that idea to make the staged H-bomb. The staged H-bomb used to be a very dark secret, but the combination of Richard Rhodes "Dark Sun" and that Progressive Magazine article kind of let out at least the general H-bomb concept. Teller's stamp on the staged bomb was that prompt x-rays from the atom bomb would be the way of getting compression instead of Ulam's original idea of the shock wave, but that the radiation would act first is obvious once anyone with physics knowledge starts working on a staged design, and Teller kind of took all the credit.
But the actual staged H-bomb not only focuses A-bomb radiation to compress a pile of deuterium, it also compresses a plutonium "spark plug" in the middle to make Ulam's staged A-bomb. The combination of heat and pressure from the radiation compression along with the flood of fast neutrons from the plutonium spark plug manage to fuse the deuterium, which produces its yield mainly in the form of yet more neutrons, which provides fission of a U-238 blanket to provide much of the explosive power of the bomb.
Fusion is really, really hard, even with the heat and pressure from an atom bomb, and the real H-bomb is a Rube Goldberg set of multiple effects which use fission-driven neutrons to produce fusion neutrons to produce gobs of explosive power from non-critical fission of U-238. Fusion is really, really hard, even for the Sun, because while the Sun is not using deuterium but straight hydrogen, for all of the intense heat and pressure in the interior of the Sun, the reaction rates are really, really low, which is a good thing, because otherwise the Sun wouldn't have lasted 5 billion years to allow us to be here.
So back to the fusion power reactor. All of the claims of imminent fusion power are based on using lots of tritium for D-T fusion for the same reason that Teller's Classical Super would have needed gobs of tritium and for the same reason that the actual H-bomb that burns D-D needs three stages of fission to get its explosive power. Just as the need for tons of T made Teller's Super a non-starter, the need for tritium means that the current frontier of fusion power is a non-starter. Yes, you breed tritium in the lithium blanket, but you have to compare the breeding doubling time with the half life of tritium and wonder how much seed tritium will you need to get a fusion power economy going and how many decades of breeding tritium will be required to switch the economy over the fusion power before the oil runs out.
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Re: (Score:3, Interesting)
Why spend billions re-creating something on earth which already exists 93 million miles away -- the sun.
It has been keeping us warm and feeding for millennia. The fossil fuels we now burn are nothing more than stored solar energy. This means that all that carbon we are now releasing must have been on the surface of the earth at one time in order to participate in photosynthesis. For that reason alone, all this glob
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Care to cite your sources on this? Because the IPCC report that was published recently suggests almost the opposite. Already warm clima
ICF, not MCF (Score:5, Informative)
Re:ICF, not MCF (Score:5, Interesting)
The plasma in a fusion reaction does not fall apart due to gravity. The effects of heat (and thus pressure) is much higher than those of gravity.
ICF in this form may work, but do they have a method to harvest energy yet? are they close to break even? In theory one could capture emitted alpha particles (they have an energy/speed of several million electron volts, which translates to a very small current of a few million volts), but AFAIK, nobody has done such a feat yet.
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See the Z Machine (Score:5, Interesting)
Yikes! (Score:2)
--
Mr. Fusion on your roof: http://mdsolar.blogspot.com/2007/01/slashdot-user
Constant of nature (Score:3, Funny)
not 20 years off (Score:2)
I understand this as "this machine could be the basis for a new power plant design within 20 years from now".
seems like a long wait just for a theoretical power-plant draft...
No, it WASNT always 20 years (Score:5, Informative)
I worked in that department for 3 summers (Score:5, Interesting)
I also wouldn't want to live anywhere near there; it feels like a moderately strong earthquake in the area everytime they fire that thing; it seems like the ground beneath and around a rapid-fire facility would quickly weaken and collapse.
So yes, the Z machine is an excellent source of x-rays, and those x-rays can definitely be used to collapse a fusion capsule, but how applicable is it for fusion power?
Bussard's Polywell fusors? (Score:3, Informative)
Interesting, how that relates to Rober Bussard [wikipedia.org]'s Polywell fusor [wikipedia.org], which he claims can be made into a prototype 100 MW plant in 7 years [emc2fusion.org], provided the needed 200M USD funding [nmcf.org]?
You can also listen to his lecture at Google Tech Talks in 2006 [google.com] to get an idea of what he's up to.
BTW, you can donate to this fund via Paypal [nmcf.org] and sign the petition [petitionspot.com] to renew his funding from the government.
Re: (Score:3, Informative)
(I watched that presentation and while it was compelling, I actually think the funding decision made is the correct one. There's a couple of things he really ought to show on a smaller scale before trying the $200 million project; I don't think he's anywhere near exhausted w
Re:Bussard's Polywell fusors? (Score:4, Informative)
Nope, it appears that it was a [slashdot.org] false [fusor.net] alert [blogspot.com]. "The contract has merely been continued for a year without funding".
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Z-Machine (Score:4, Informative)
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Re:it's a steam engine (Score:4, Informative)
Steam turbines are probably one of the most efficient pieces of technology in the power generation industry. More power is lost in the transmission lines (typically 7.5% per 100 miles) than the steam turbines lose.
Reference: http://www.engineersedge.com/thermodynamics/power
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