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More Evidence for Tabletop Fusion
heptapod writes "Researchers at Purdue University have statistically significant evidence that their tabletop fusion experiments were successful. Yiban Xu's experiment different from an earlier Oak Ridge experiment using a different and cheaper source of neutrons than Oak Ridge's pulse neutron generator. Surpassing break-even point still eludes the grasp of science."
Surpassing break even is easy, we did it decades ago... What we are missing is a really big boiler, to make it work.
"Surpassing break-even point still eludes the grasp of science."
hmmm does it?
- "Hear that?! The percolations are imminent! Cease your ingress!"
Will we get it before or after Duke Nukem Forever?
Statistical evidence of fusion at this level is indeed impressive; however, while fusion experiments such as this others remain below the break-even point, they shall yet be little more than a labtable source of neutrons. We await developments from the latest in the field.
Are they counting break-even as getting back more energy than needed to operate the ultrasound source ou they did count also the expense of producing the deuterated acetone and their expendable neutron source?
It reminds me of when people say hydrogen burning cars will solve all emition problems because they produce water. They don't count the emissions that may be needed to produce, compress and ship the hydrogen to the nearest gas station.
http://www.dieblinkenlights.com
"The process is analogous to stretching a slingshot from Earth to the nearest star, our sun, thereby building up a huge amount of energy when released," Taleyarkhan said. I sure hope their process can be done easier than their analogy!
Robert Bindler
A Computer Science student's views on technology.
So... that Mr. Fusion I ordered off of eBay will actually work?
#define CLUE 0
I expect to to be 2050 when we get fusion.
Well...at least that's when Sim City let me build one...
Hey, my coffee's getting cold.
Would you mind nuking it for me.
"When it's time to railroad, you get railroads." Or however the saying goes.
This question is one I've been thinking about for a few years now due to an idea for an invention I've got (not cold fusion, though), plus some stories I know of. The most relevant one is an episode of Outer Limits (the series from the 90s, not the one from the 60s).
In the story, an expelled physics student detonates a small 'cold fusion bomb' in a campus clocktower as proof of the technology, then takes a physics class hostage with another device. He demands that the people who have tormented him in the past be brought to the courtyard and shot in front of him, or he'll detonate the more powerful device he's got with him.
While the military is trying to figure out what the hell it was that detonated (since they don't believe in a cold fusion bomb), the negotiator is trying to figure out what the deal is with the hostagetaker. It comes out that, among other things, he believes there's a reason we've not found any signals from other species. The cold fusion technology is so simple that anyone can make it. When a species gets advanced enough to realize how easy cold fusion is, he says it's inevitable that a species will destroy itself before it can get mature enough to handle its technology. The negotiator then says, well, tell us what led you to the idea, and we can try to steer science around that until we can mature enough to handle it. The guy thinks back to what started him on the path to cold fusion - a physics test with the question, "Demonstrate why cold fusion is impossible."
I'd say it's inevitable that we WILL have this technology. How simple it winds up being is unknown at this point, of course, but hopefully it'll be complex enough that not every nut in a garage can do it.
of Cold Fusion, a technology that promises clean power in future (and prevent wars over oil). Just wondering why governments are so indifferent to Cold Fusion.
hilarious
I think this has some potential for abuse. Do we want this power to get into the wrong hands?
That's the very question currently being asked at the Pentagon. Just what will our government due when a drop on productivity is caused by millions listening to music with an ever-lasting battery in their iPods?
Life is not for the lazy.
It reminds me of when people say hydrogen burning cars will solve all emition problems because they produce water. They don't count the emissions that may be needed to produce, compress and ship the hydrogen to the nearest gas station.
The trick with this one is in the may.
Maybe someday we'll find a technology that's clean-burning and energy-efficient to the point where oil is no longer the most cost-effective way to make energy. Say, maybe nuclear fusion. Or maybe oil will eventually get so expensive that other energy technologies start to look not so bad by comparison. But if we ever reach this point, because of the massive installed base and economies of scale of oil systems, especially the ones in cars, we and our economies will still be dependent on oil. So it won't matter that the newer technology is better, we'll keep using oil anyway. That's bad.
Hydrogen may at first be ultimately dependent on "dirty" oil and coal to make the hydrogen in the first place, but because it decouples energy production from energy use, in the long run it gives us the capacity to move on to better energy sources. It's like a nicotine patch, okay, it technically doesn't address the addiction but the thing is eventually you get to take the nicotine patch off.
On top of this, there are situations where if you can't eliminate emissions, moving the emissions is a desirable second best thing. Like, of course we're not making advances in our contribution to global CO2 levels if all these cars in the city burning oil are replaced with a bunch of cars burning hydrogen [PLUS] one huge smoke-belching oil-burning hydrogen plant. But, well, if the city is Los Angeles, and the city is basically one huge smog-trapping bowl surrounded by mountains, and the smoke-belching hydrogen plant is on the other side of the mountains, then never mind the global CO2 levels, you've still made Los Angeles a significantly more pleasant place to live.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
I wouldn't toss ITER aside before I get to at least read the journal article on a few of these desktop setups. I'd still like to see what pressure they're operating at, temperature ranges, D/T enrichment, reaction rate, bubble size, mcnp models (a vised geometric plot at the least), fluent models, etc. I just don't trust science magazine or a run of the mill newspaper to publish groundbreaking science that's on par for an engineer to read, since those cater to people without much knowledge of the engineering feat discussed in the article. But that's the nuclear field (or any engineering for that matter), we're supposed to be skeptical as hell until it's widely duplicated. If I can do it in my lab, then I'll believe it. Or at least see it in someone else's lab who built it from scratch from nothing but the other researcher's blueprints. And controlling plasma with magnets isn't too hard, in fact it's down to nearly an exact science where only a few unknowns remain, mainly the occurance of MARFE's, diverter material protection, and so forth. The largest problem lies with protecting the magnets from the 14-MeV neutron flux exiting the core. But still, I wouldn't toss aside ITER just yet. It's got some work to do, but it's a pretty sound model for a large scale fusion power plant.
Seems pretty easy to me:
Step One: Build a sonoluminescence apperatus using an ocilloscope, a sine generator, audio amplifier, piezo transducers and spherical flask. Details here: http://www.physik3.gwdg.de/~rgeisle/nld/sbsl-howto .html
Step Two: Build a neutron supply source, problalby most easily constructed is a farnsworth-type fusor: http://en.wikipedia.org/wiki/Fusor (makes a great science project too)
Step Three: Get some deuterium and dissolve it in acetone, place in your sonoluminescence apperatus and start tuning it to produce bubbles. Availible at your local scientific supply store.
Step Four: Build your own neutron detector and confirm the bubbles are producing fusion: http://home.earthlink.net/~jimlux/nuc/ncount.htm
Step Five: Become the envy of the neighbourhood as the only guy on your block with a nuclear fusion device in your garage! (to avoid police suspicion call it a magical glowing bubble maker)
Step 6: Profit!
Ok, let me ask this. Why is this on AScribe and not on Nature?
I won't belive it until it's published on a peer reviewed journal.
Where's the nuclear powered car we were promised back in the 1950s?
Some genius figured out that providing every man, woman, and child with sufficient nuclear material to create an atomic pile wasn't such a good idea?
From a technology perspective, there were a few other problems as well. Off the top of my head:
- Radiation: You need a lot of shielding to stop the "hard" stuff like Gamma, Neutron, and X-Ray bursts from escaping a functioning pile.
- Weight: All that shielding results in a lot of extra weight.
- Inefficiency: A "simple" atomic pile may be relatively safe (from a runaway reaction perspective), but it's not particularly efficient, nor can it be actively controlled.
In any case, the Ford atom car was never seriously developed. It was just an "Atoms for Peace" idea that was kicked around as a promotional gig.
A far better use for nuclear tech is in Merchant ships. Today's merchies pay extraordinary amounts for diesel fuel, have limited range, and burn fuel at the rate of gallons per feet. Nuclear reactors could provide these ships with more cargo space (no fuel tanks!), greater speed, longer endurance, and better turn-around times.
Unfortunately, the case of the NS Savannah turned off the private sector to the idea of a nuclear merchant ship. There was no real problem with the ship herself, but rather the fact that she was ahead of her time (crude was still VERY cheap back then) and one of a kind (no infrastructure to support her) meant that she couldn't compete in the market.
The equation today is a very different one from the equation back then, but concerns related to the control of reactors and nuclear fuels have placed road-blocks in the way of reviving the idea.
Javascript + Nintendo DSi = DSiCade
I agree that mainstream fusion work will be important and is probably the right track toward a practical fusion powerplant.
However, remember that Cathode Ray tubes were also once little more than a labtable source of tightly controlled electrons. New sources of materials often lead into practical applications not originally envisioned.
It is impossible to enjoy idling thoroughly unless one has plenty of work to do.
- Jerome Klapka Jerome
That's right folks, come on down to Crazy Harry's Particle Superstore. Electrons! Protons! We've got neutrons for half the price of our competition! Mention this ad and get 10% off your next order of quarks!
Coder's Stone: The programming language quick ref for iPad
It's interesting that the original professor's experimental results were discredited by the methods he used to detect fusion. First he detected neutrons, but then there was controversy about whether he was detecting fusion neutrons or png neutrons. Then, when he changed certain things, and still detected neutrons... everyone questioned whether or not they were background neutrons or fusion neutrons. Basically, they wanted to see the moment of neutron detection coincide with the moment of light creation down to the nanosecond (I think).
Now, these guys are using other methods of detecting fusion by neutron energy levels, and tritium. I just hope that the levels they detected were WAY above the statistical normal amount of 2.5MeV neutrons and tritium in deuterized-acetone controls.
New sources of materials often lead into practical applications not originally envisioned.
This is so true. No-one making velcro thought it would be good for strippers. It took their wives to figure that one out.
You are so wrong it's not even funny.
The industrial revolution started because of forest depletion in England which meant that they had to switch to coal. In order to get to the coal they invented the steam engine to pump water out of mines and lift people into and out of them. The invention of the steam engine had the wonderful side effect of bringing forth the industrial revolution from which we all benefited.
If you want to read about the reasons for societal development and collapse by a academic whose works on civilization have stood the test of time and explain the Roman, Mayan, Mezoamerican and Egyptian collapses all with the same theory I suggest you read Tainter's collapse of complex societies. The west has saved itself from collapse for longer than any other civilization out there because we have had the wonderful luck to constantly innovate ourselves out of the corners we get into. There were many times throughout the Renaissance and the industrial revolution that European society could have collapsed but we always managed to pull ourselves out of it via technolgy.
In this case, the important ingredient is deuterium, which can be extracted from sea water. If there is anything that Earth has a lot of, it's sea water. So with any luck you are wrong.
I don't care if it's 90,000 hectares. That lake was not my doing.
On a large enough scale, vulcanism would be reduced. It's a win^3 situation.
Sure, you'd win, but what about Spock and T'Pol? What about Tuvok?
You're a Romulan in disguise! Admit it!
Visual IRC: Fast. Powerful. Free.
However, as a geek, I know that the Dark Ages were as much caused by the change in the fuel economy from wood to coal as the retreat of the Roman Empire.
However, as a pastry chef, I know that the Krebs cycle causes metal fatigue in steel structural support beams.
However, as a ballerina, I know that the Pythagorean theorem causes the release of neutrons from radioactive material.
However, as a professor of French literature, I know that penicillin causes cost overruns in long-haul LTL shipping.
All employees must wash hands before seeking equitable relief.
So you're worried that this might lead to a technology that could devastate the earth? I guess you've never heard about Nuclear Weapons, some of which are in the hands of some not so wonderful people, such as Kim Jong Il of North Korea. Sorry bud, you're trying to close the barn door after the horse has already left, about 60 years to late I might add. On the other hand, if this were an easy way to make large amounts of U-238 and Plutonium then I might be worried.
I would love to see some hard documentary evidence on this point. From my knowledge of history, it was precisely the use of coal as a fuel source that triggered the Industrial Revolution. Almost immediately prior to the widespread use of coal in England, the primary fuel source was wood or hydro power (for running mills and stuff). There was a huge debate in England at the time because the forests were visibly disappearing from all over the British Isles, and doom and gloom were predicted (as supposedly did happen at Easter Island). After coal was used in large quantities, England went from a largly agrarian lifestyle and small villages (London had only about 30,000 people in the year 1400) to a major industrial power. The use of coal had a major impact on that occuring.
When coal was finally excavated in large quantities, there was a need for bulk shipments of the stuff overland to larger concentrations of people who needed it. From this came railroads, steel production, mechanical and civil engineering, and a modern industrial economy.
As far as the Great Depression being caused by a shift from coal to oil, that is incredibly simplistic, and there were many causes for what happened, including a lack of securities oversight (triggering the Wall Street Stock Market Crash of 1929), overproduction of food stocks, preditory pricing companies, and reconstruction issues from WWI where the bill to pay for that awful war finally came due and had to be paid. Conversion from coal to oil may be there as a slight cause, but nearly as significant with those fuel sources was the conversion from passenger rail travel to personal automobiles... which really didn't happen until the 1950's in the USA anyway.
What a fusion energy economy would actually provide is a cheap energy source that would cause a huge expansion of economic resources for just about everybody, even in the most poor parts of the world.
It could be argued that the wealth a person has is determined by the amount of raw power that they have available to do what they want to accomplish. This is actual power, as measured in kilowatt-hours, joules, or whatever. If you want to increase the wealth of a region, you need to provide energy resources that will allow the people in that area to be able to accomplish whatever task they set their mind to accomplish. In this regard control of power is also control of political power, as utility companies are quite aware of.
What project like this tabletop device, a Fusor, or even Cold Fusion offer to provide is the potential that you don't need utility companies to provide this energy for you. If you need the power to run an air-conditioner, you just prime your fusion reactor with a little hydrogen gas and some water (to extract some more hydrogen gas). And not much water at that either. And no need for rolling blackouts or even power surges on the power grid.
Geeks successfully decentralized computing power, so why not power generation itself? I for one look strong with anticipation and excitement for the future this may bring.
BTW, I think it will be 1st world nations that will be able to take advantage of a hydrogen economy first before most 3rd world nations. If you look at China, they are incredibly heavy users of coal right now, with manufacturing plants that are actually producing steam-powered locomotives as new products (and hudreds to thousands of deaths every year in the coal mines from accidents). If anything the Chinese experience is that they have had to go through the entire industrial revolution, but at a greatly accelerated pace compared to most western European countries and North America. Africa is in political turmoil that almost seems to resemble what Europe was like in the early part of the 2nd millenium, and simply won't get much of anywhere (except for a few minor countries who get it) until they resolve their political issues and stop the nearly constant state of warfare in Africa.
Not only that, but fuel for very large diesel engines contains lots of residual oil, and is very high in sulfur. 5000 ppm plus. I understand that England recently traced the source of some acid rain problems to maritime activity. They've practically eliminated their sulfur output from coal power plants, etc, so boats are now the biggest producer.
That heavy diesel fuel is nasty stuff. Basically, its what's left over after they boil off all of the gasses, gasoline, kerosene, road use diesel fuel and the lower grade heating oils. They have to pre-heat it quite a bit to get it to burn in an engine, otherwise it's about as good as filtered crude oil--slightly less viscous.
Nuclear power would be a huge step forward in this area... I can't agree more. Throw in some modern reactor and propulsion designs and you'd have a terribly efficient and manuverable ship. Might even make fuel a bit cheaper for the rest of us if it caught on... Bonus.
Constitutional rights may be respected, repealed, or modified; but they must never be ignored.
However, as a geek, I know that the Dark Ages were as much caused by the change in the fuel economy from wood to coal as the retreat of the Roman Empire.
Or in other words, "as a geek, my knowledge of history is really skewed".
The Dark Ages were hundreds of years before the switch to coal. Coal mining started around the time the dark ages were ending (circa the 11th century), and the fuel economy didn't switch wholesale until hundreds of years after that.
-- Alastair
Whatever they hit, it becomes radioactive and more fragile.
An exaggeration. Hydrogen atoms, for example, merely become deuterium atoms, which are not radioactive.
Which is why neutron shielding tends to be made of things like lightweight polymers that contain lots of hydrogen atoms. (In the early days before modern plastics, they used paraffin wax.)
There are other materials that can happily absorb a neutron and go from one stable isotope to another.
-- Alastair
You can get tabletop fusion with a TV high voltage supply, a glass bulb, some wire, and deuteriums gas. That's been known for decades and is used as a neutron source commercially. People build those things for science fairs. It's called the "Farnsworth Fusor" (I know, in light of Futurama it sounds like a joke, but the fictional character was named after the real one).
Why don't we all have flying cars, then? Because you can't get a net energy gain with the Farnsworth Fusor--it seems to be impossible in general to do so, the numbers just don't work out.
Of course, even if you do make it efficient, it's not exactly "clean energy": even with so-called aneutronic fusion, a few percent of the fusion reactions will generate neutrons, which, for realistic power generation, results in a neutron flux that causes the power generation to be quite dirty. Not as dirty as fission--disposal should be easier--but don't expect something harmless you can just run in your basement.
So, tabletop fusion isn't really anything impressive: there are probably lots of ways of getting fusion on your tabletop. The question is how you make it efficient enough to useful amounts of energy out of it. And cavitation seems no more promising there than inertial confinement in the Farnsworth Fusor. But maybe if enough people keep playing around with this, someone will get lucky and find something that works.
OK then, Just in case anyone else is as thick as me: Don't check the parents of these replies unless you want to spoil your pleasure in reading the latest Harry Potter.
RTFA:
Researchers have estimated that temperatures inside the imploding bubbles reach 10 million degrees Celsius and pressures comparable to 1,000 million earth atmospheres at sea level.
This is NOT cold fusion, this is sonofusion.
Iraq: war to save the U
There was a BBC Horizon documentary on this nuclear fusion sonoluminescence phenomenon that casts strong doubt on the validity of previous work conducted by this researcher. The acid test for the occurence of fusion is the release of a neutron at the exact instant that the flash of light from sonoluminescence occurs. The Horizon team used a detector that can record the neutron releases at the required instant in time. After recreating Taleyarkhan's experiment according to his published journal papers, results were disappointing. None of the neutrons that were detected occurred at the same instant of any of the sonoluminescence flashes. The extra neutrons were explained away as originating from the emitter used to generate bubbles, or from external sources. No doubt rivals will challenge the statistically significant tritium claim. Tritium does occur naturally in significant quantities in any mass of heavy water (deuterium oxide).
About coal being worse than nuclear, I have not the best references, but here are a few:
/ FS-163-97.html / colmain.html
http://geology.cr.usgs.gov/energy/factshts/163-97
http://www.ornl.gov/info/ornlreview/rev26-34/text
http://yarchive.net/nuke/coal_radiation.html
Remember the year 2000? They promised us flying cars. They delivered the PT Cruiser...
Unfortunately, there are still problems with modern-day pirates in a few places in this world. Worrying about the loss of a standard diesel powered ship is bad enough, but the loss of a nuclear powered ship would be even worse.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
The Soviets built some nuclear-powered ice breakers.
"Long run is a misleading guide to current affairs. In the long run we are all dead." (John Maynard Keynes)
So what would happen if you used deuterated acetone in a cavitaion device such as the hydrosonic pump? (see, http://www.hydrodynamics.com/product_pics.htm)
Everything I see on this shows there doing the work under atmospheric pressure. I really think they need to move to very high pressures and check the fusion rates agianst pressure. Although sonolumnescence under extreme pressures is probably a big research area in general you would expect the liquid/phase to become more ordered resulting in higher collapse energys potentially very high somewhere in the phase diagram. In fact if I'm right then there is a very high probability that gas giant planets actually heat themselves via this sort of high pressure desktop fusion instead of simply heat from contraction. I bet with the wealth of organic/organometallic substances/mixutures and high pressure phases you can hit the perfect system. I googled around to see if anyone has measured neutron emission from gas giants and drew a blank. Does anyone know if its ever been measured ?
I may not be the GP, but I'll throw in my $.02 as a fusion science researcher. (I work on a magnetic confinement device myself.)
1) The running joke of fusion is that it's always 30-50 years away. This is more due to meager funding levels than anything else. At a talk by a PPPL scientist a few years back, it was mentioned that if one plots the price of oil and the amount allocated for fusion research versus year, they track rather nicely. (The 70's were a great time to be in the field!)
Why the meager funding? Fusion researchers kind of shot themselves in the foot in the late 50's and 60's, before much of the underlying plasma physics was well understood. TFTR (the Tokamak Fusion Test Reactor, built in the late 70's, ran through the 90's) turned up physics phenomena that were unexpected and needed to be understood. (That can still be said for many devices today, which are built to specifically analyze these phenomena.) When Nature deals you a bum hand, you have to go back to the drawing board -- and push things off for another decade. Politicians don't like that -- especially when they've been coerced into thinking past their next election!
ITER will be a very large-scale test device. Some of the phenomena that we see disrupting our current experiments are related to physical device size. Additionally, fusion power production is volumetric, while losses from the plasma come from the surface area of the confined plasma. Therefore, scaling up the size will boost fusion output, making it easier to "breakeven" (power out == power in) and, in ITER's case, very likely "ignite" (after reaching a critical temperature, you can turn off external heating and the plasma burning supplies the rest).
Of course, such scaling takes Lots of Money. Superconducting magnet coils are pricey; so is requisite neutron shielding. Current designs incorporate a Lithium "blanket" which will both absorb the 14 MeV neutrons (shielding) and produce tritium (amazingly, more T than you seed the plasma with initially!). One of the biggest question marks is in the field of materials. Nothing has been built that is going to take the neutron punishment that ITER will dish out to plasma-facing surfaces. It is such an important task to design materials that can sustain bombardment that a separate facility will be constructed simultaneously with ITER in Japan to study neutron bombardment exclusively. This has implications in the divertor material (high-Z tungsten or something lighter?) as well as blanket design.
2) My personal opinion is that it is best to stick with our Gen-IV nuclear plants when it comes to fission. These are meltdown-proof, high-efficiency plants that are designed for rapid implementation, should there be a willing buyer. A tabletop-size fusion device would be a relatively inefficient method of starting a fission plant; there are plenty of natural neutron sources that can be made by mixing radioactive materials together. Essentially, it'd be cheaper to use our existing designs for a big fission plant than mixing a fusion reactor's blanket design with a subcritical fission design.
"The Health Hazards of Not Going Nuclear", by Petr Beckman. Out of print and somewhat dated (about 20 years old), but goes into the different problems with coal versus nuclear power. Multiple copies available at abebooks.com
I hear it's ~10 $G for iter. That's not exactly chump-change. Especially since we're not actually sure that even after ITER we'll have a working plant or a path to one. In addition, your scaling arguments (I've heard elsewhere that the minimum size of a plant would have to be ~10 GW) imply very very large plants. That may be to large to be feasible - a 10GW plant is a pretty big investment.
One problem with very large tokamaks is that although they are above breakeven, it's not by much - which means that you have to recirculate large amounts of power. That makes for a very large and expensive generator facility.
I also understand that the amount of tritum circulating in a working plant would be enormous; much, much larger than ever used before. Tritium is notoriously hard to keep contained - so it's not obvious that a fusion plant wouldn't have issues with radioactivity releases...
My personal opinion is that it is best to stick with our Gen-IV nuclear plants when it comes to fission.
(Actually, I wasn't thinking of a hybrid based on tabletop fusors, but rather tokamaks). Wouldn't a hybrid allow you to use a smaller (and presumably more feasible) tokamak as a neutron source, while at the same time the sub-critical fission blanket could be designed very safe, since neutron economy isn't such a driving concern? You can imagine a blanket that gives a gain factor of 100, and a tokamak at 0.1 of breakeven, and you still have a feasible plant.
In addition, it would allow you to burn U238 or even nuclear waste instead of just U235. Seems like a win-win-win to me. Fusion gets operational experience and increased development funding, the country gets a good nuclear energy source, we're no longer oil-dependent or dependent on limited amounts of U235, and it reduces the waste issue (which is what is going to kill even the Gen IV plants). As an aside, it's interesting to note that even nuclear weapons are fission/fusion hybrids... we've never extracted pure fusion energy in any quantities, controlled or not.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
A friend of mine was working in a lab at an island somewhere in the pacific. He said that he was very close to achieving TableTop fusion. No word from him yet. Its been almost 50 years and still no word since his last mail.