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British Researchers Say Fusion Is Close
sh00z writes: "The article quotes a leading scientist saying that Fusion power is 'within reach' in the next decade, with commercial plants to follow within another 10 or so years. Shhhh. Don't tell anyone at Texas A&M. They might just jump the starting gun again."
For years, fusion has been 50 years away. To find out what date most people think fusion will become practical, all you need to do is add 50 to the current year. That means that fusion will be practical in 2051.
Of course in 2051, fusion will still be 50 years away.
Amazingly, by calculating the density and power requirements of the latest and greatest CPUs from Intel, we get the same number. By Moore's law of fusion, the heat and energy available to start a fusion reaction in a typical Intel processor doubles each year. By a simple formula, you can determine that in the year 2051 Intel CPU's will be so hot they can fuse hydrogen! This amazing calculation through two independent means confirms the majority opinion: fusion is still 50 years off.
I'm sure there's somebody out there trying to imagine a Beowulf cluser of fusion processors.
If tits were wings it'd be flying around.
IIRC, these folks are all using a tritium-deuterium reaction, which yields helium and a neutron. For one thing, it's a much easier reaction than, for instance, deuterium-deuterium, and, for another, the neutrons give you a way to extract the energy and manufacture tritium. Of course, the other thing the neutrons do is irradiate the structure of the reactor, which ends up leaving you with all sort of fun radioisotopes to dispose of later.
Of course, that probably pales by comparison to the amount of waste generated while refining fissile fuels, and you completely avoid the possibility of a meltdown, but still, I might not go so far as to claim it's 'pollution free.'
What needs to be understood is that they've managed to use a fusion generator to generate electricity. However, they've never managed to create electricity in a useful fashion.
As it stands, they can create an efficient reactor that is not self-sustaining or a self-sustaining reactor that is not efficient. In other words, the former uses very little outside power, but isn't stable and ceases to function. The latter is more stable, but uses more fuel than conventional means.
Fusion power is not a pipe dream. Just as conventional power reactors have been improved over time to produce electricity more efficiently, so will fusion reactors eventually be improved to the point where they're useful. Will it be in the next decade? It may well be, but regardless of when it will happen, it will happen.
Virtue finds and chooses the mean.
Aristotle, Ethica Nichomachea
anybody got any info on what tech problems?
MAST is a spherical torus....and ST's are suppose to solve a few issues that tokamaks (doughnuts) where found to have. First Tokamaks reuire a very large magnetic field for containment. Producing the magnetic field is probably the biggest overall cost money and energy-wise. An ST, like MAST or NSTX (www.pppl.gov/projects/pages/nstx.html) or the machine I'm chained to NSTX's little brother CDX (w3.pppl.gov/~cdx) use proportionately less external field that a tokamak would need for the same plasma current. For fusion reactor design that's a big advantage for the ST.
The ST also hopes to solve a real plasma physics issue...MHD instabilities. Making cold plasmas isn't all to difficult. Once you start pumping energy into the plasma you get very exotic plasma wave physics that can tear the plasma apart. You can design some of the instabilities away, if your design is clever enough....is the ST a clever enough desgin? I don't know. but ST's do allow access to a new regime of labortory plasmas
There are a lot of unresolved issues in magnetic confinement fusion. The ST machines are definitely worth exploring but it's not clear that a working fusion reactor will be based on anything like MAST.
-jef
im too tired to write anything longer
Damn Cold Fusion! I was starting to really enjoy the rolling blackouts, besides the super long coffee breaks, I got to grope the hot intern in the copy room when the lights went out.
-- ;-)
Kuro5hin.org: where the good times never end.
Well.... cold fusion is already commercially available
____
Sometimes the voices in my head speak over each other. This is one of those times.
Codeposition fusion might not only relieve a significant portion of our dependence on foreign oil (and we all know how important that is), but it might also be a natural way to retrofit our dangerous, dirty fission nuclear plants. Codeposition fusion produces nearly zero ionizing radiation of any kind, and no nuclear waste products.
Here are three good references:
"Calorimetry of the Pd + D Codeposition," by S. Szpak, P. Boss, and M.H. Miles, in Fusion Technology, volume 36 (Sept. 1999), pp. 234-241. search near the end of this page for the abstract ("...excellent reproducibility, high power outputs....")
"On the behavior of the cathodically polarized Pd/D system: Search for emanating radiation," by S. Szpak, P.A. Mosier-Boss, and J.J. Smith, in Physics Letters A, volume 210 (1996) pp. 382-390. (Phys Lett A is much easier to find than Fusion [Science and] Technol.)
"Calorimetry of Pd+D Codeposition in a Fleischmann-Pons Dewar Cell," by M.H. Miles, S. Szpak, P. Boss, and Martin Fleischmann (March 2001) abstract on web only
In short, codeposition fusion reliably produces a 500% power gain without fast neutrons, high-energy radiation, or radioactive waste. The peak of the energy produced is in the infrared, with x-ray production just 9% above the baseline in a lead cave, and gamma-ray production only 2% above a lead cave's background levels. There is a very high likelihood that codeposition fusion will soon be commercialized to drive electrical generation turbines, helping to reduce our dependence on fossil fuels and, given sufficient electric vehicles, foreign oil. The cost of codeposition fusion electricity is likely to be less than one cent per kilowatt hour.
You may have heard that cold fusion was discredited. Early experiments used smooth, solid palladium cathodes, which did not produce reliable results. Some such smooth, solid cathodes would run for weeks without producing excess heat, and then would do so for perhaps a few days, and often would never do so again. Over 400 studies in the peer-reviewed scientific literature -- see: the Dieter Britz bibliography [about a megabyte] -- have confirmed that the effect is certainly real, but is only reproduceable in less than one out of ten attempts. Those who have studied codeposition fusion get 99+% reproducibility, and precise control of the effect. The crucial difference is that codeposition cathodes are mossy and dendritic, instead of smooth and solid. Any kind of mossy, high surface area cathodes produce much better results than any smooth cathodes, but they were not in common use until a couple years after the poor early results had discredited the entire field.
Of the six laboratories in the U.S. publishing cold fusion research, three are in California, one is in Mountain View (First Gate Energies), and one is in Menlo Park (SRI International.) Szpak et al's lab is in San Diego. The governments of Italy, France, Russia, Japan, and China all sponsor cold fusion research in their own national laboratories. However, the budget for cold fusion here in the U.S. is very small, because the entrenched plasma fusion "big science" community (whose most optimistic estimates indicate that plasma fusion will not be viable for another thirty years -- and even then it will produce nuclear waste; perhaps more than fission does) keeps funding away from cold fusion (which does not produce nuclear waste or dangerous radiation) through continued, unfair ridicule.
Cheers,
James
I wonder if this is a Boron-Hydrogen CBF reactor they are talking about. These sorts of reactors have two plasma streams guises by magnetic fields. The two plasma beams converge at high energy and Hydrogen whams into Boron fusing but causing the new Boron-12 radioisotope decays in about .0202 seconds down into three alpha particles with very high velocities which are guides through an energy converter (a magnetic coil) which generates electricity with a pretty high efficiency. You also end up with clean byproducts rather than Tritium-Deuterium fusion (heavy water fusion) I keep seeing pushed by researchers and oddly enough the DOE. I don't get how the DOE could keep a straight face whilst pushing the cleanliness of fusion power talking about heavy water plants. Tritium product isn't exactly cheap or easy considering you get it from sticking lithium into a laser implosion chamber because tritium is pretty damn rare naturally. Shit the only two facilities they've got working on the waste products are MIT and INEL (Idaho National Energy Laboratory) which is a fraction of the effort they're putting into everything else. This is what got us into the mess of nuclear waste disposal in the first place.
BTW, heavy water fusion (the fusion of H-2 and H-3) yields an alpha particle and a free neutron. Both of these byproducts are moving really fast after the reaction. The helium isn't much of a problem considering it has a charge and can be confinsed and controlled by magnetic fields. The neutrons however have no charge and thus fly in whatever direction they were originally headed. Thus heavy water reactors need lots of shielding and cooling systems due to the thermal pollution of the energetic neutrons. This adds up to alot of wasted energy in the form of heat (about two thirds of the total energy from the reaction). You can run the coolant through exchangers to get some energy back out of it but you're left with the same radiactive problems fission reactors have to deal with. Namely contamination. CBF's using Boron-Hydrogen or Helium3-Deuterium don't need this sort of extra bulk and also are more efficient since alot of their energy is being directed by the magnetic fields of the reactor and harnessed. They can thus be smaller and more efficient so instead of one big reactor you could have a handful of 100MW reactors distributed in a region. Oh yeah, for nuclear nuts I didn't go into He-3/H-2 fusion because He-3 is so fucking rare on Earth it would literally cost you billions of dollars to collect even a little bit for industrial use. Until we can efficnetly mine the Moon and asteroids and eventually the outer gas giants (Uranus and Neptune first and Jupiter and Saturn when we can have an efficient way of escaping their gravity) we're not going to be using He-3 for industrial purposes.
I'm a loner Dottie, a Rebel.
I recently earned a BS in physics and am now taking a year off before going to grad school (deferred admission to Berkeley). Fusion research is not my specialty, but I do know people that work in this area, and I think I can offer some insight into the issue.
Let me start by saying that cold fusion != fusion research. Cold fusion as popularly described has been debunked. The researchers in question were good people who were mistaken about what they observed, unfortunately when they were given proof of their mistake they chose to disappear from the public eye rather than admit their mistake. No low temperature fusion has ever been verified, though occasionally you will see new proposals for how it might be possible.
Now the real stuff. This means high temperature, high pressures, and almost exclusively isotopes of hydrogen (deuterium and tritium). There are three successful ways that man has produced fusion: Hydrogen bombs which are heated by one or more fission bombs, confined plasma (ie. tokomaks), and pulsed laser pellet experiments.
H-bombs are pretty useless because there is no way to make a small controllable explosion. All you can ever get is really big ones that would be impractical as a power source.
Pulsed laser experiments experiments involve using arrays of uber lasers to heat and compress solid hydrogen pellets so fast that they reach the point of fusion before the gas can dissipate. People in the physics community generally see this tech as a dead end because the technical requirements seem to scale exponentially with linear increases in power output. There is still research being done, but the power consumption of the lasers is orders of magnitude more than what little energy the fusion generates right now, so it's unlikely to see this being practical in the next half century.
Tokomaks are the standard in confined plasma fusion, though there are a couple alternatives that have some physicists excited. Tokomaks work; they just don't work very well. Right now we have machines that about break even, ie. they generate enough energy to run themselves. Given how much energy is involved just running the machine, if you can get another factor of 10 out of the best machines of today, you'd have enough for a useful small-medium scale power plant.
Confined plasma fusion is alluring for a number of reasons. The source hydrogen is easy to obtain or make (tritium is often created in fission reactors by exposing deuterium to nuetrons). The radiation is very safe compared to fission reactions. In both fission and fusion the components of the reactor itself will pick up some radioactivity, but the real concern in fission is all the spent fuel. You can't keep it where it is because it's no good as a fuel source and you don't want to dump it anywhere else either. In fusion reactors, the spent fuel is typically less rather than more dangerous when compared to the fuel itself, and contains no mid-range decay lifetime isotopes of the type which are most troublesome in fission reactors. Lastly, confined plasma can't have a "melt down", if the plasma gets too hot or electricity is turned off, the fusion reaction stops itself.
Contrary to popular belief, it's not just output that's a problem, the things are very large and complicated. I remember a story I heard about a group who spent 2 months taking apart, fixing, and putting their machine back together again, despite knowing at the start what piece had broken. If it's going to be profitable you need technology that is stable, long-term and easily repairable. Right now, fusion is none of these. Part of the drive for smaller machines is that they should be easier to maintain and less prone to fail. The trade off is that smaller machines need tighter confinement than their large cousins and thus are harder to engineer.
Two decades is somewhat optimistic for commercial appliations, but the state of technology is such that the next generation machines by the end of the decade should be a good 20% or so above break even (not wide scale useful but something to notice). If we can keep progressing at the current rate (and there is enough inventiveness and creativity in the field to suggest that's possible) then I would think prototypes for small power plant type models might be ready by 2040 or so.
Of course then again I'm a physicist and we have a horrible track record in predicting the rise of fusion technology.
Tampons and Beer... that'll need a lot of marketing to overtake Gin and Tonic.
...it's about 149 597 870 kilometers away.
93 million miles and an ozone layer seems about right.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks