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Amateur Scientists Seek Fusion Reaction
Posted by
kdawson
on Mon Aug 18, 2008 08:37 PM
from the things-that-hopefully-do-not-go-boom dept.
from the things-that-hopefully-do-not-go-boom dept.
ElvaWSJ writes "A small subculture of amateur physicists and science-fiction fans — fewer than 100 worldwide — are building working nuclear-fusion reactors at home. The designs are based on the work of Philo T. Farnsworth, an inventor of television, from the 1960s. Some of these hobbyists hope similar reactors can one day power the planet, but so far they consume more energy than they create."
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Submission: Amateur Scientists Seek Fusion Reaction by Anonymous Coward
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Can a String Theorist? (Score:5, Funny)
Re:Can a String Theorist? (Score:5, Funny)
Because for every hobbyist who builds one of these hoping to get more power than they put in, there's someone in the background playing a violin...
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Re:Can a String Theorist? (Score:5, Insightful)
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Re:Can a String Theorist? (Score:5, Funny)
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Re:Can a String Theorist? (Score:5, Insightful)
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Re:Can a String Theorist? (Score:5, Insightful)
No, no, no. Seriously. It's a limitation of the design, not the idea of a fusion reactor.
Bussard's "whiffleball" reactor design looks promising, and there are a few others which may succeed, but building one of those which will actually generate power is (unfortunately) financially out of the reach of any mere hobbyist.
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Re:Can a String Theorist? (Score:5, Insightful)
...but building one of those which will actually generate power is (unfortunately) financially out of the reach of any mere hobbyist.
Right! Which is pre-cise-ly why mere hobbyists were totally unimportant when steam engines were superseded by explosion/electric engines, when electricity superseded town gas, or when heavier-than-air craft superseded dirigibles, or when modern biochemicals/genetics/pharmaceutics took off after the '70s. And to the whole transistor -> chip -> microcompting discontinuity thing.
No 'amateurs' there, no sir-ee. No bycicle mechanics either. Or cofee plantation heirs engineering in Paris. Nooo-sir !
What's more, personal fortunes were much greater and lives-of-leisure more common (and acceptable) in those days than in our own more proletarian and democratic (or board-cratic) era.
So its quite improbable that anyone nowadays will have enough money and free time available to turn these 'hobbies' into 'serious' research. No free time. No wealthy patrons. And resistance is IR^2, damn!, I mean : futile. :)
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No, it's about scale (Score:5, Insightful)
Now look at a float glass plant, a steel continuous casting and rolling mill, or any likely practical fusion design. They simply do not work at small scales, therefore they cannot be developed by cottage industry.
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Re:Can a String Theorist? (Score:5, Funny)
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whatcouldpossiblygowrong (Score:5, Informative)
Does anyone remember the "radioactive boyscout"?
David Hahn to make his own reactor (breeder, i think). He accumulated quantities of radium and tritium from smoke detectors and lantern mantles in a shed. The DOE had to lock down his parents whole house and yard to clean it up.
David Haun [wikipedia.org]
Re:whatcouldpossiblygowrong (Score:5, Informative)
Hahn was arrested [nwsource.com] last year for trying to steal smoke detectors from his apartment complex.
Judging from his mugshot [blogspot.com] he looks to be suffering the effects of radiation exposure.
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Amateur Scientists Seek Perpetual Motion Device (Score:5, Funny)
Good article.
Michelson (Score:5, Informative)
" The designs are based on the work of Albert Michelson, co-proponent of luminiferous aether theory, from the 1890s."
It's worth reminding people that, whatever his original views of luminiferous aether, Michelson was one of the great experimentalists of the 19th century and his name is most firmly associated with the experiment that's widely credited with experimentaly destroying the credibility of aether theories [virginia.edu].
(It's still possible to come up with aether theories even with the Michelson-Morley results (and the results of hundreds of other people who replicated and refined that result), but it's much more difficult, and the resulting theories end up rather hard to credit.) I assume that the original use of the word "proponent" was a typo).
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Re:Amateur Scientists Seek Perpetual Motion Device (Score:5, Insightful)
*Arapidlyspinningblackholesayswhat?
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Re:Amateur Scientists Seek Perpetual Motion Device (Score:5, Interesting)
You can't "gain free energy", but you can transfer energy from say, a planet, to say, a spaceship.
http://en.wikipedia.org/wiki/Gravitational_slingshot [wikipedia.org]
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Re:Amateur Scientists Seek Perpetual Motion Device (Score:5, Funny)
That's funny. I usually waste my mod points modding down posts that start with variations on "Go ahead and mod me down." I guess this is your lucky day.
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What could possibly go wrong? (Score:5, Interesting)
All known hydrogen fusion reactions produce strong neutron fluxes. Strong enough to kill, and death by radiation poisoning is not my idea of a fun time.
Re:What could possibly go wrong? (Score:5, Interesting)
All known hydrogen -hydrogen fusion reactions produce strong neutron fluxes. Strong enough to kill, and death by radiation poisoning is not my idea of a fun time.
There, fixed that for you.
The holy grail for Polywell fusors is proton-(11)Boron fusion [wikipedia.org]. Aneutronic, and generates alpha particles which are almost trivially easy to convert to electricity.
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Re:What could possibly go wrong? (Score:5, Funny)
So don't forget to wear you film badge. Because nothing says safety like a device that can tell you after the fact that you've received a fatal dose of radiation
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Re:What could possibly go wrong? (Score:5, Funny)
Shoot, I just spent all this time building a Farnsworth fusor for nothing.
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Not power generators (Score:5, Insightful)
Despite the fact that this is a link to a non-technical publication's website, the Farnsworth Fusor [wikipedia.org] is a real fusion device and works basically how they describe it. What it is not, however, is anticipated to ever be a viable power source, and there are significant theoretical hurdles to prevent it from being viable relative to other approaches (and when you make any kind of fusion reactor seem plausible in comparison, you're probably not going anywhere). In my experience, most hobbyists are well aware of this and just enjoy the tinkering.
The primary functions of a fusor are 1) Generate neutrons 2) Look really cool 3) Kill you with extremely high voltages if you screw up.
Why didn't they mention the polywell? (Score:5, Interesting)
Focusing on Farnsworth fusors in an article written in part about fusion as a possible energy source seems as poorly researched as writing about steam engines in an article about internal combustion. The polywell [talk-polywell.org] seems be the heir apparent for serious work in energy out of the fusor lineage.
Philo T. Farnsworth (Score:5, Interesting)
.
Best book [eht.com] on the early days of television that I have read. The above quote is from page 126.
WMD (Score:5, Funny)
In other news, a small subculture of amateur neoconservatives are building working homemade tanks, fighter jets and cruise missiles in order to seek out and destroy these Weapons Of Mass Destruction before its too late and a mushroom cloud appears in somebody's basement
As others have said ... (Score:5, Insightful)
I don't think anyone building these expects to ever have a net power output from them -- that's not the point. The point is to be able to say you built a fusion reactor, or as others have said to generate isotopes for other experimenting, etc.
IMO, a more important area of amateur and admittedly fringe scientific research around fusion and fusion-like reactions is the several hundred teams that still continue to this day to investigate what the heck is going on with low temperature fusion. Tons of progress is being made in the field, and some reasonable theories are starting to form. There's a lot of unknowns, but helium is regularly produced, neutrons are regularly produced and more interesting from a theoretical standpoint, lots of atoms are changing from one element to another...
Its like the 1700's experimenting with chemistry. Lots of people doing lots of very cool and interesting experiments and getting lots of very interesting results, even if we (humanity, not me personally) still don't quite get it.
IMO, its an aspect of science we miss in the modern world. These days we just assume we understand things pretty well and experimenting is about engineering or proving a theory. Its cool there are still areas of fundamental science experimentation going on where we just don't get what is happening and have no idea what might happen with the next variant.
Fusion? BAH!!! (Score:5, Funny)
next to his bed? (Score:5, Funny)
Apparently, he never wants to get laid ... EVER!
Re:next to his bed? (Score:5, Funny)
And if he does, he needn't worry about birth control...
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brilliant (Score:5, Interesting)
As someone who has worked in fusion, there is significant radiation created by the process. The larger reactors can't run on the ideal deuterium/tritium mixture because it would irradiate entire cities while the reactor burned. I would not want a small one in my garage. The reactor I worked on was in a concrete bunker a fair distance away from any people. It was also the size of a large house.
If you want to live in the future and be on the cutting edge of science, go to grad school and study physics (you're never too old). There are not enough people seriously studying fusion. You'll get paid to work on reactors (big or small) which may have a commercial future. We wear snarky shirts that no one understands too.
farnsworth (Score:5, Funny)
Why isn't this tagged with "goodnewseveryone"?
What about gravity? (Score:5, Funny)
Re:Good grief... (Score:5, Informative)
No, this really works as advertised. It's a high school science faire level of complexity and cost (if you're willing to deal with stray neutrons). For practical reasons, it can't be made to produce more energy than it consumes, is all. The principles have been known since the 20s. Robert Bussard (of Bussard Ramjet fame) had patents on it.
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Re:Good grief... (Score:5, Informative)
But the stray neutrons (or other energetic particles, depending on the reaction) are the real problem with fusion as a power source. To quote TFA:
Fusion advocates say reactors would be relatively clean, generating virtually no air pollution and little long-lived radioactive waste. Today's nuclear power plants, in contrast, are fission-based, meaning they split atoms and create a highly radioactive waste that can take millennia to decompose.
The spent fuel from a fission reactor is just not that hard to deal with - park it in a contianment area as robust as the reactor itself for 5-10 years, and you're left with not-very-much not-very-radioactive waste that could be easily disposed of, if it weren't so valuable that we insist on keeping it instead.
It's the rest of the reactor that's the serious problem. Depending on the reactor design, quite a bit of the reactor structure can become radioactive over time.
Fusion is going to have the same problem. Even if you have a reactor vessel the size of a washing machine, you're going to need significant shielding, an energy transfer mechanism (water leading to a turbine or something), structural elements, etc. Surem the problem with spent fuel goes away, but the problem with speant reactors remains. Not something you'd want in everyone's basement.
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Re:Good grief... (Score:5, Informative)
But the stray neutrons (or other energetic particles, depending on the reaction) are the real problem with fusion as a power source.
That actually depends on what your fuel source is. The common science fair level project uses hydrogen (not deuterium, even), and produces, IIRC, neutrons. There are other fuels possible, and some don't produce much of anything nasty. IIRC, Lithium 3 on one side and Lithium 4 on the other produces stable helium isotopes, and electricity, and absolutely nothing else.
There are still issues with fuel that misses other fuel striking internal components of the reaction chamber, which can produce some radioactivity, but getting to the self-sustaining point will also greatly reduce this sorts of unwanted collisions and ther resulting radioactive byproducts.
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Re:Good grief... (Score:5, Insightful)
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Re:Good grief... (Score:5, Informative)
The patents apply to a fancier version called the Polywell. Polywell attempts to cut losses to the point where net power is possible. As far as I know, no hobbyist has attempted that one yet. It's a much more expensive design that, depending on the fuel, would generate truly lethal doses of neutrons, and would need lots of shielding.
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Re:Good grief... (Score:5, Informative)
Actually, Bussard was trying to use a Boron-11 fuel matrix that doesn't release neutrons in the same fashion as Deuterium fusion does. One of the reasons for this is precisely to help cut down on the neutron flux coming from the reactor.
His design goal was to use it as a direct drop-in replacement for boilers at coal-fired power plants, using similar sorts of shielding and precautions as would be already in place for such a facility. Water in the boiler itself would offer what extra protection would be needed, and radiation levels for released radioactive products would be lower than would be typical for a coal plant as well.
FYI, coal plants release far more radioactive waste per kWh generated than the worst and most inefficient nuclear power plants... with perhaps the singlar exception of Chernobyl. Even that I'm not 100% certain of.
This said, you are correct that the fusion rate in a Polywell is something of a much greater concern if you actually got one going, and would be leathal if it used traditional fusion fuel targets.
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Re:Good grief... (Score:5, Informative)
I said per kilowatt-hour produced. Geesh... did you even pay attention to what I had to say?
Chernobyl was awful, and I don't dispute that. I also noted it was a major exception to the general rule. The one thing that makes Chernobyl so incredibly awful is due to the fact that all of the material is concentrated in one place. The reason I hesitate about how damaging it was in comparison to coal is due to the fact that Chernobyl is not only a major facility, but that it is still supplying electricity to the Grid in Eastern Europe.
It is likely that Chernobyl would beat out a coal plant using sources particularly high in radioactive elements in terms of kilowatt-hours of energy produced, but I don't think it would be several orders of magnitude higher. Keep in mind that the coal plants spew this "waste" willy-nilly all over the entire area where they are located, and over the course of decades and not all at once like the Chernobyl disaster did. I also lack all of the specific numbers to do a strict comparison.
That facility is also an example of awful engineering that simply wouldn't happen in the regulatory environment of western governments, but that is a separate issue.
As far as citations or evidence, I could give dozens here. Here are a couple that perhaps you ought to read if you don't want to believe little old me:
At least so far as some "common sense" stuff, keep in mind that coal comes from underground sources and that often that coal is mixed with a whole bunch of other elements, including nearly every naturally occurring radioactive element on the Earth. Trace amounts of Uranium alone is sufficient to spread huge amounts of low-level radiation over nearly all of the soot fall-out that comes from the burning of coal... and that goes right up the chimney.
BTW, as far as the nuclear industry being aware of this... it has been "common knowledge" for decades. They have used this argument, but very few people are really paying attention. Certainly not the "greens" that get into an uproar over the construction of nuclear power plants. This isn't in the major news media outlets because it isn't really even news. There isn't anything "new" about this sort of information, even if it may be a revelation to you.
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Re:Good grief... (Score:5, Interesting)
James Lovelock [wikipedia.org] and Patrick Moore [wikipedia.org] (Greenpeace co-founder) are just some of the people pushing for increased use of nuclear power at the moment.
Nuclear power is indeed cleaner than coal and is the only realistic alternative to coal available today for baseline power generation.
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Re:Good grief... (Score:5, Informative)
Are these the same yahoos that post videos of "perpetual" motion machines on Youtube?
No. Wikipedia is your friend. [wikipedia.org]
Farnsworth - Hirsch - Meeks fusors are quite real and effective. They're easy to build even by hobbyists using readily obtainable parts. Commercial versions serve as controllable neutron sources. Fusion neutron output of up to a trillion per second has been reported and rates in the billions per second are easily obtainable. To date it is estimated that Farnsworth-Hirsch-Meeks fusors have produced far more total fusion neutrons than all other non-bomb fusion devices combined.
Downside is that they involve ions moving in a trajectory past a metal electrode, which they must pass without hitting many thousands of times on the average before they participate in a fusion reaction. Hitting the electrode loses the energy used to create the ion and attempt to confine it, dumping the energy as heat in the electrode. Getting the electrode to be sufficiently "transparent" to achieve breakeven seems to be a lost cause.
Bussard's family of Polywell fusion machine designs apparently started as an attempt to steer the ions around the inner electrode of a Farnsworth-Hirsch-Meeks machine using a magnetic field. But it has since developed into a different (though related) principle: Use the magnetic field from the self-shielding magnet/electrodes to confine electrons (which are much easier to handle), creating a high-density space charge in the center of the machine. Use the electrostatic field of the electrons to attract and confine the ions in this region at high density and temperature, resulting in fusion. The magnetic field still shields the inner structures and the field is convex toward the plasma, limiting the plasma instabilities the plague "conventional" fusion machines. [wikipedia.org]
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Real fusion (Score:5, Informative)
There was an article by Tom Ligon in Analog back in September 1998-- it's available on the web [fusor.net] if you're interested in more details.
This is pretty cool. I love amateur science.
With that said, note that there is a vast difference between merely demonstrating fusion, and producing usable power by fusion, roughly similar to the gap between the glow of your old radium watch dial, and a nuclear bomb. But if the hobbiests can learn to scale it up... now, that would be cool.
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Re:Real fusion (Score:5, Insightful)
There are some hard limits to what a typical IEC fusion reactor can produce... as the "grid" that encloses the fusion core also tends to absorb some of the particles that are needed to sustain the reaction.
What the IEC (Internal Electrostatic Confinement) reactor does really well is produce a stable neutron source that can be turned on and off with a switch. There are some very useful applications for such a device in terms of nuclear physics research and medical treatments where this would have tremendous value even if you can't reach anything even near a break-even energy production for the device.
For a medial device, it is really nice in terms of being able to have a neutron source that can be turned off, pulled apart for maintenance, and when the equipment is de-commissioned or surplussed you don't need to get deal with radioactive waste disposal. It can also be installed without having to get special permits from the Atomic Energy Commission.
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Re:Good grief... (Score:5, Insightful)
No work is being done, so therefore no energy consumption is required.
By the same token glue would be producing energy by making two things stick to each other...
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Widely used in medicine and research (Score:5, Interesting)
Farnsworth fusors are widely used in medicine and research as an easily controlled and cheap source of neutrons.
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Re:Really? (Score:5, Interesting)
Its for the tinkerer who wishes to learn more about high vacuum pumps (absorption, ion, vane, turbo...), vacuum chamber design (welding, management of outgassing...), low pressure measurement, low pressure gas flow, high voltage (flybacks, diode stacks, corona discharge, flashover...), particle detectors (scintillators, avalanche photodiodes, image intensifiers, calibrated op amps...), instrument design (fast ADCs, multi-channel analyzers...), oh and some cool stuff related to nuclear physics thrown in. Most of us can't buy all the gear, so we make it all from scrounged parts. And learn a tremendous amount of related engineering in the process. Look at it this way - its like the difference between building an RC car and rebuilding a classic car - anyone can toss together a kit, but if you want to learn how to restore an older car you end up learning dozens of skills you didn't realize you need. Its one of the most interesting educational projects in modern science that isn't illegal (yet).
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Re:Radioactive Trajedy (Score:5, Funny)
Sweet. They built a time machine.
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Re:Fusion? Pah! I've done them better! (Score:5, Funny)
Burger King and Taco Bell? You could do so much better. Let me help.
Step 1: Broccoli and Cheese soup. Crush some Oyster Crackers into it and DON'T forget the Tabasco sauce.
Step 2: Pork and Beans. 1 Can. Always a classic.
Step 3: ONE foot-long-cheap-ass Don Miguel burrito (the spicy red one). Can be purchased at any fine 7-11 anywhere. Only ONE. Trust me.
Step 4: 5 Hardboiled eggs with salt and pepper.
Step 5: Steamed Cabbage and 2 raw onions with plenty of butter.
Step 6: A single large bag of Funyuns.
Do all of this within 3 1/2 hours. Sit on the couch and wait about another 2-3 hours. Hold everything in till about 6 hours after you started.
You know that saying "killed the dog"? Well if you have pets, I don't recommend this.
DISCLAIMER: If you have any kind of a heart condition, or if anyone else in the house has one DO NOT ATTEMPT THIS.
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Re:by working you mean failing (Score:5, Insightful)
No, no, no. It's not "almost" fusion. It is fusion. It is almost a fusion generator. That doesn't mean fusion isn't occurring. It means that the reaction is not self-sustaining. There's a huge difference. Saying that it isn't fusion is like saying that a match placed in a sealed jar and set ablaze using a laser isn't really fire because it consumes all the oxygen and burns out and there's no way to add more oxygen....
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Re:there was a high school kid (Score:5, Insightful)
having said that, what these guys are doing is still important in terms of awareness and getting the good word out. we NEED fusion power. to save us from pollution, global warming, petrodollar funded russian neoimperialism and islamic fundamentalism, etc.
We have plenty of fusion power.
We've got a 1.989e30 kg fusion reactor producing approximately 386 billion billion megawatts of power.
We just don't harness it very efficiently at the moment.
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Re:Has someone tried,.. (Score:5, Informative)
Here's an honest question: where do our iron deposits come from?
Um ... from dead stars that had enough mass to produce iron (as well as even heavier elements) as they died. This means stars that were much more massive than our little sun.
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