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Amateur Scientists Seek Fusion Reaction 401

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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Amateur Scientists Seek Fusion Reaction

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  • Really? (Score:2, Interesting)

    by AmonEzhno ( 1276076 ) on Monday August 18, 2008 @09:45PM (#24653601)
    So wait... why build a reactor that produces a negative output? I'm all for home tinkering, but this seems a little extreme...
  • by L. J. Beauregard ( 111334 ) on Monday August 18, 2008 @09:48PM (#24653629)

    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.

  • who built a tabletop farnsworth reactor a few years ago

    its technically challenging to build one of these, but not beyond the skillset and material list of a committed and persevering amateur science buff

    however, saying that once you build one you can work towards self-sustaining fusion is like saying after playing with legos you can go build a pyramid. well yea, you have the conceptualization down, but you still need to move heaven and earth and invest trillions

    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.

    and one of these guys just one day may provide the mental spark to get working a real breakthrough in the field, or inspire a kid somewhere to wonder in awe, and he grows up to provide that mental spark of a breakthrough. anyone who doubts that is just way too jaded

    so i salute you amateur fusion researchers

    keep hope alive

  • by CustomDesigned ( 250089 ) <> on Monday August 18, 2008 @09:53PM (#24653675) Homepage Journal

    Farnsworth fusors are widely used in medicine and research as an easily controlled and cheap source of neutrons.

  • Re:Really? (Score:5, Interesting)

    by kbonin ( 58917 ) on Monday August 18, 2008 @09:56PM (#24653703) Homepage

    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).

  • by Anonymous Coward on Monday August 18, 2008 @09:57PM (#24653709)

    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 [] seems be the heir apparent for serious work in energy out of the fusor lineage.

  • Philo T. Farnsworth (Score:5, Interesting)

    by QuietLagoon ( 813062 ) on Monday August 18, 2008 @10:03PM (#24653781)
    Now nearing the ripe age of fifteen, Philo Farnsworth turned his team of horses around at the edge of the field and surveyed his work. Before him lay his mowed hay field, clearly delineated rows cut in alternating directions. Suddenly the future hit him with a vision so startling he could hardly sit still: a vision of television images formed by an electron beam scanning a picture in horizontal lines....

    Best book [] on the early days of television that I have read. The above quote is from page 126.

  • Fusors are Old News (Score:4, Interesting)

    by istartedi ( 132515 ) on Monday August 18, 2008 @10:05PM (#24653799) Journal

    As the summary acknowledges, the fusor has been around for a while. If it were theoreticly possible to get net power gain, don't you think it would have been tried?

    I doubt many of the people experimenting with the fusor are seriously trying to get net power gain. It's useful as a neutron source. Thus, you could make isotopes with it. That's rather scary, and something that I'm sure a lot of people would not want advertised; but it's also common knowledge for anybody who has an interest in nuclear science.

  • by fm6 ( 162816 ) on Monday August 18, 2008 @10:43PM (#24654089) Homepage Journal

    Every hobby has its hazards. Building a fusor is probably safer than, say, mountain climbing. In both cases, you could die a nasty death if you're not careful. Serious practitioners are careful.

  • by Zobeid ( 314469 ) on Monday August 18, 2008 @10:47PM (#24654111)

    I was wondering exactly the same thing. In my view the Polywell is the most interesting thing going on in fusion research these days, and it's a direct descendent from the kinds of devices these hobbyists are building.

  • by cunniff ( 264218 ) on Monday August 18, 2008 @10:51PM (#24654143) Homepage

    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 []. Aneutronic, and generates alpha particles which are almost trivially easy to convert to electricity.

  • brilliant (Score:5, Interesting)

    by Goldsmith ( 561202 ) on Monday August 18, 2008 @11:06PM (#24654255)

    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.

  • by BlackSabbath ( 118110 ) on Monday August 18, 2008 @11:08PM (#24654285)

    You can't "gain free energy", but you can transfer energy from say, a planet, to say, a spaceship. []

  • by budgenator ( 254554 ) on Tuesday August 19, 2008 @12:09AM (#24654665) Journal

    Just the law of the conservation of energy and matter... energy or matter can neither be created nor destroyed.

    That not what happens, E = mC^2, so a little tiny spec of mass can be converted into a great deal of energy with no change in the total E * m of the system. With these fusor they'll never get past break-even because the containment fields require more energy to maintain than the reaction releases; think of it as changing electricity into neutrons with the fission as an intermediate step rather than a power source.

  • by Anonymous Coward on Tuesday August 19, 2008 @12:40AM (#24654801)

    In terms of string theory? I think you needs a pretty sturdy set of shoe strings to pull yourself out of the swamp and make this work.

    And by work I mean achieve a net-exergonic reaction. Right now this doesn't work anymore than a car without an engine - once you push it forward, it kinda drives. But it's not really useful.

  • by hughk ( 248126 ) on Tuesday August 19, 2008 @03:40AM (#24655617) Journal

    I don't think you can call the gasses in the solar core loose. There are also some pretty awesome magnetohydrodynamics involved. In the end almost every high-energy photon produced will spend a looong time bouncing around the core (I've heard estimates of up to 50 million years) being absorbed and re-emitted ensuring that much of the energy stays in the core.

    Actually it is that last bit that probably does it, the large quantity of emitted energy that ends up being recycled to maintain the reaction. That is the difficult bit with a Farnsworth Fusor

  • by Jesrad ( 716567 ) on Tuesday August 19, 2008 @05:51AM (#24656173) Journal

    "before its too late and a mushroom cloud appears in somebody's basement"

    I for one cannot wait for the moment one of those amateur fusion tinkerers vaporizes his own house in one humongous boom. I'll be there and cheering when it happens.

    Do you know why ?

    Because it'll signal the end of a whole era. Have you followed the research domain of LENR/CANR - formerly known as "cold fusion" - over the years, for example ? There you have thousands of labs all around the planet making endless refinements and taking almost infinite precautions so they make the most impossibly-deniable measurement of some excess heat when electrolyzing half a pint of water.

    This is madness ! That kind of exercise in pointless "due process" is an incredible waste of time ! That's at best undergrad routine, it should be reserved for the time when LENR/CANR/LANR/whatever-it-is makes it to mainstream acceptance, and be funded with leftover budget while the big names focus on the Big Things like earning a Nobel rewriting our understanding of chemistry and building net power generators and licencing the tech all around.

    What those guys really need to build acceptance and make a true breakthrough is one of them to go in a huge boom that razes a whole wing of the electrochemistry department building, a boom so big no one can pretend with a straight face that the excess energy in the beer-mug-sized jar was just a measurement fluke. A large fireball rising amidst flying debris and thunder ! What better pan-in-the-face demonstration of useable excess energy or net power gain can you wish for ?

    How many brilliant chemist careers were started by exploding hydrogen-filled balloons and/or dumping raw sodium metal in water ? This is what we really need: more big booms for science's future ! More awe in the eyes of the passers-by ! Nuclear technology did not build such a pervasive recognition in the mainstream throughout the 50s by merely splitting some atoms inside a heavy graphite box, but by expanding radioactive mushrooms of fiery hell to the stratosphere !

  • Re:Bring on fusion! (Score:3, Interesting)

    by Ihlosi ( 895663 ) on Tuesday August 19, 2008 @07:25AM (#24656609)
    I just want to say one word to you - just one word. Plastics.

    And why would you need oil if you have enough energy to synthesize any hydrocarbon of your choice on an industrial scale ?

  • Re:Good grief... (Score:1, Interesting)

    by iwbcman ( 603788 ) on Tuesday August 19, 2008 @08:13AM (#24656875) Homepage

    Just don't pay too much attention to what these shills are saying. I consider articles concerning energy on slashdot as a kind of opportunity to practice anger management. The pro-nuclear fanboys that so utterly dominate slashdot have been so thoroughly brainwashed by that industry that they are only capable of equivocating and spreading falsehoods.

    Although I am very reluctant to make such accusations, being that this comes awfully close to actual conspiracy, a thought which I almost always argue against, sheer ignorance cannot account for the level of equivocation which one sees being put forth on these forums. Most of these people were not even born when America had a large anti-nuclear movement. They do not remember the issues which people fought about and against which people protested. If you are old enough to remember these things, coming to slashdot you feel like you have wandered into the twilight zone, kind of like being in a parallel universe where the past the we know simply never occurred.

    But what can we really expect? We have had 15 years of paid shills being used to manipulate the public opinion-including "scientists" bought and paid for by the large economic interests which see and cast the environmental movement as the heir apparent of the "commies".

    What is so truly sad is that almost nobody in America can even remember that environmentalist movement was not merely lamenting the negative ecological impacts of our energy policies but perhaps more importanty attacking the tremendous centralization(monopolization) of capital and power which is synonomous with big energy.

    This social justice aspect of the environmental movement which at its roots is defying the profound concentration of wealth and power and working towards environmental solutions which empower the individual and communities has been almost completely swept under the rug. None of these pro-nuclear fanboys even begin to address the larger socio-economic problems which have always played a crucial role in the environmentalist movement.

    The patent intellectual dishonesty which equates the environmental lobby with big energy, is the same as that which equates coal plants "radioactivity" with that of nuclear power plants, that which talks about "clean coal" and nuclear power being "green"-doublespeak, in classice orwellian tradition.

    If you listen too closely to these shills you begin to believe that nuclear power is infinite clean energy and that it produces only negligable byproducts which pose no threat at all. You begin to believe that the environmental movement and those who have engaged themselves in the fight against big energy are all bought and paid for by some vast conspiracy of evironmental lobbiests who have endless amounts of money to spend fighting the poor misunderstood behemoths of the energy industry.

    And of course you also start to think that everyone who questions the wisdom of such energy policies are all just ignorant uneducated people who have no idea what they are talking about.

    Open your nose, follow the money and soon enough you can see where this shit is coming from.

    But of course- pecunia non olet. Bullshit

  • by Ihlosi ( 895663 ) on Tuesday August 19, 2008 @08:25AM (#24656973)
    Is it reasonable to assume that all the materials on earth came from a single supernova, or is that overly simplistic?

    That would be overly simplistic.

    The solar system is roughly 5 billion years old, the universe is roughly 13 billion years old. The early universe contained more supermassive stars than today's universe, and these giants only had lifespans in the tens of million years. So a lot of them popped before our solar system formed. It is believed that our solar system formed in the vicinity of several earlier supernovas.

  • Re:Good grief... (Score:5, Interesting)

    by cheesybagel ( 670288 ) on Tuesday August 19, 2008 @08:45AM (#24657101)
    So your objections against nuclear power are concentration of wealth and power? Are you an environmentalist or a closet anarchist?

    James Lovelock [] and Patrick Moore [] (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.

  • Re:Good grief... (Score:5, Interesting)

    by Teancum ( 67324 ) <robert_horning AT netzero DOT net> on Tuesday August 19, 2008 @08:48AM (#24657129) Homepage Journal

    The "pro-nuclear fanboys" that you are complaining about here are the engineers who know a hell of a lot more about nuclear power than you do... partly due to the fact that they are in the trenches helping to design these things and have a hell of a lot better knowledge about basic physics than you seem to be demonstrating with this sort of posting.

    If this gives me a chance to vent my spleen, so be it.

    I will admit that there are issues well above and beyond just the raw design of the reactor, and the concentration of wealth/power that comes from the building of a major nuclear power plant is a huge issue as well.

    One of the advantages of the polywell reactor is that it would de-centralize the building of power plants, and put them on the scale of a neighborhood plant that wouldn't be a major terrorist target. This is a reactor that conceivably an ordinary person in a 1st world country could own on their own, or at least it could be owned by a small non-profit group.

    Another of the more interesting applications that Bussard and his team came up with was a nuclear-powered semi-truck using this technology. He didn't think he could get it any smaller than something on the back of a semi-trailer rig, but it could be used on that scale and haul freight on that sort of scale. That the radioactive products would be low-grade enough to allow transport on public highways is something to think about as well.

    Of course all of this depends on getting the Polywell to work in the first place. While there have been some interesting promises, Bussard had his funding dry up right before he died. There is a group that was able to get some continued funding on the idea, but it is in the backwater of the R&D development.

    As an extra note, the reason why there were budget cuts for this line of fusion research: The war in Iraq. Seriously. That was the explicit reason given by the OMB about why this research program was cut. Now mull that one over for a little while. This is about the "greenest" form of power production that I can even think about, yet because it is "nuclear", the green movement doesn't want to touch it at all.

  • Re:Good grief... (Score:5, Interesting)

    by drakono ( 1339167 ) on Tuesday August 19, 2008 @09:40AM (#24657617)
    Great googly-moogly. More FUD.

    up to 500 micro-sieverts each hour

    1 sievert (SV) = 100 rem So, we're talking about tens of milli-rems per hour. Great. You get cosmic radiation at a higher rate than that by flying on an airliner.

    a no-dive zone was self imposed by Greenpeace's radio-protection officer

    Yeah, like that means anything. Just more food for the FUD.

    French Environment and Health Ministries commissioned an official epidemiological study of leukaemia around La Hague

    Over ten years ago, studying a quickly-appearing illness. No results? No surprise.

    Measurements taken by OPRI near the beaches detected no radioactivity above the natural radioactivity level

    See? Greenpeace has no substance to their argument.

    I'll admit that no plant should circumvent the guidelines, nor should they then hide that fact. But the facts are that the safety guidelines are many times more strict for nuclear power than for any other type of power. I don't mean precautionary measures, I mean environmental impact. Coal plants release many times more radiation, spreading it over large areas via their smokestacks, than nuclear plants could even dream of. Even wind power has a greater carbon impact than nuclear power -- from start to finish, including building infrastructure, mining uranium, and handling the waste. Again, La Hague seems to be acting in an unethical manner, but I just can't stand all the ignorance about nuclear power.

  • by Teancum ( 67324 ) <robert_horning AT netzero DOT net> on Tuesday August 19, 2008 @10:35AM (#24658415) Homepage Journal

    I would have to agree with you to a perhaps much more limited extent:

    The fusion design that has been getting all of the attention is the Tokamak design, where all of the billions of dollars and thousands of professional engineers and physicists have been working toward. After all of the money and decades of research, I think it is fairly safe to say that this line of research is at or very nearly at the end of the road in terms of what else they are going to learn from it.

    If you compare this to computer technology, it is like trying to build a full modern computer using vacuum tubes in logic circuits. You ended up with monster computers like the ENIAC or UNIVAC that worked, but pushed the technology right to its edge and demonstrated that something else was needed in order to significantly scale down the complexity of the design.

    What is needed for fusion research is to find the equivalent of a semi-conductor solution that can significantly reduce the size of the needed components and allow a major break-through in terms of efficiency and power output.

    Just as semi-conductors haven't completely replaced vacuum tubes, any new breakthrough in fusion power generation will have to come from some place completely different.

    It should be noted that the IEC reactor (aka the "Farnsworth Fusor") is something that has only recently been explored to any major extent, and even this is only by mostly amateur researchers. It certainly isn't something that a complete knowledge of the technology has been obtained about, nor have there really be "decades of research" on the concept.

    The Polywell reactor is a direct descendant of the IEC, and there may be other similar kinds of designs. Bussard even gives credit to Philo Farnsworth and his research, and goes into what the actual limitations of the basic IEC design might be as well as noting how the Polywell design tried to overcome some of those limitations.

    This certainly isn't a scientific well of ideas that has been exhausted.

  • Fusor Documentation (Score:2, Interesting)

    by cyanoacry ( 702918 ) on Tuesday August 19, 2008 @11:51AM (#24659581)

    I've built a fusor while in high school (a couple of years ago), and it's certainly within the reach of a dedicated person, or somebody with lots of support.

    More info for the interested at [] .

    For me the fusor wasn't really an end so much as a starting point: it is an educational experience that is unmatched, because to build a fusor, you've got to have a grasp of high voltage, high vacuum, and gas management systems. Learning about these things in theory is nice, but there is nothing that can compare to slaving over a hot wrench after bolting down your chamber for the last hour and leak checking every single seal.

    And, if anything, it does look good on a resume.

  • by ElizabethGreene ( 1185405 ) on Tuesday August 19, 2008 @01:59PM (#24661641)

    Excellent explanation. I'll take it one step further.

    Recently, there was a rather famous Google Talk by the founder of Energy Matter Conversion Corp, a DARPA funded energy research company. They built a series of fusors using "Inertial Electrostatic Confinement", which eliminated the wires using an array of electrical coils. This research appeared quite promising, but the project was shuttered for political and budget reasons.


  • by Teancum ( 67324 ) <robert_horning AT netzero DOT net> on Tuesday August 19, 2008 @02:32PM (#24662081) Homepage Journal

    The Polywell attempts to combine "the best" of both types of fusion reactors, as it tries to set up a "magnetic bottle" that can contain an electric charge that does pretty much the same thing as the Fusor in terms of trying to confine the nuclei of fusible atoms. Since the electrons creating the electrical field are contained in a magnetic structure instead of a physical metallic structure, it solves two things at once:

    • Removes the pesky wires that the nuclei keep banging into... giving more energy back into the system.
    • Allows the reactor core to get to much higher temperatures that can be substantially warmer than the melting point of a conductor like gold or copper.

    Still, there are a number of other issue and things unique to the Polywell that raise questions if that line of thinking will actually produce energy as well. Some detractors of the Polywell think that some of the energy losses from its design may still not get past the break-even point, but that remains to be seen in practice.

    What you've written here, harrkev, is a good introduction to the topic. Thanks for putting this together!

Doubt isn't the opposite of faith; it is an element of faith. - Paul Tillich, German theologian and historian