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Fusion power deja vu? Call me cautious if you will, but I will wait a while before jumping for joy over this potentially wonderful news:
U.S. researchers will soon publish strong evidence of a recipe to generate fusion power with tiny bubbles, which does sound like a modern witch’s brew.
The power source is ultrasonic noise aimed at a clear glass canister whose size would qualify as a grande latte in a coffee house. The sound waves rattle through a liquid solvent in the glass and, as they do, create minute (on the order of a thousandth the width of a human hair) bubbles. Further sound causes the bubbles to expand, compress and then collapse. When they do, some of the hydrogen atoms in the liquid seem to fuse and give off light and energy.
Hmmm… What do our resident gearheads make of this?
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Sonoluminescence. Just Google on that. It’s been around for a while, still a long way from being ready for “Prime Time”. Might remain a Lab Curiousity, might someday be the Next Big Thing.
The only thing we can say at this point is that we’re now pretty sure the effect is real. Whether it can be engineered into a useful power supply is another matter.
I’ve actually seen a sonoluminecence setup running almost a decade ago–back then, the question whether there was fusion going on or not was open. I doubt this will result in net power, ever. I’d expect a Farnsworth fusor to generate net power sooner than sonoluminescence.
Years ago, I took a flyer on some stock in a company, KMS Industries, named after its founder K. M. Siegel. Siegel was an ex-University of Michigan physics professor who quit academia to attempt to make his fortune with ‘laser fusion’. He may have come very close.
The idea was to fire an array of lasers surrounding a point at which was located a tiny glass sphere filled with deuterium. The glass would suddenly absorb all that energy, vaporize and collapse at very high pressure. The energy of the collapse would be high enough to initiate fusion. Unlike ‘cold’ fusion which claimed to somehow circumvent the need to exceed the initiation energy requirement for fusion, laser fusion met that requirement, albeit on a very small scale.
The problem that KMS ran into was to make sufficiently perfect spheres in large numbers. The spheres were microspheres of the sort used in ‘scratch and sniff’ inks -the sort of thing you find in magazine perfume advertising. Instead of filling the microspheres with Chanel no. 5, they used deuterium. For a magazine ad the size and shape of the spheres is not too critical but if they are to be symmetrically collapsed by a sudden laser burst, it is all important. Apparently only one in several million was good enough. Practical power generation required a large supply which could be dropped into the laser target region one after another.
Their other problem was political. The Atomic Energy Commission had government sponsored groups working elsewhere with Tokamaks: magnetic bottles which -in theory- kept an extemely high temperature fusion reaction confined in a magnetic field (because any material out of which a container could be made would vaporize at the reaction temperatures). They were not happy about a private firm pursuing a different approach and were even less happy about it appearing to have promise. KMS eventually got neutron breakeven – more neutrons and energy out than were put in.
The situation was what would have occurred if Scaled Composites had tried to build and fly their spacecraft in 1966, in competition with the Mercury program.
I don’t know what finally happened to KMS. I still have the stock certificates somewhere. They ran out of money, got Texas Eastern Transmission, a gas pipeline company to back them for a while (apparently pipelining methane made from electolysed hydrogen is more efficient than transmitting the electricity directly over long distances because wires radiate electromagnetic energy – even if they are not attached to a radio station) They had some laser patents that they tried to market to keep going but I think they finally went under.
I’m wondering if this new approach might not be along the lines of the glass spheres. I have heard that the phenomena of cavitation -the sudden opening and collapse of bubbles in a liquid by sound waves can create huge pressures. I believe that they are a big problem in ship propeller design. If they occur, they can eat away the surface of a steel propeller over time.
So the requisite initiation energy may be present in a cavitation bubble. The problem then would be to get enougn deuterium gas into the bubble. Deuterium atoms are at least as rare in water as perfect spheres are in scratch and sniff inks.
So my verdict is that the process seems possible if the cavitation pressures are high enough (I don’t have knowledge of the numbers involved). That would be one step. Unless the fluid involved is heavy water there is still a problem of filling the bubble with deuterium. In fact, I think a cavitation bubble is filled with vacuum. Which is why it can collapse with such energy.
Power line loss isn’t due to broadcasting: it’s due to resistive losses. They are quite significant over long distances so it is more efficient to produce energy close to where is to be used. The reason this doesn’t happen as much as it once did is partially economies of scale and tradeoffs with shipping costs. It might be cheaper to build a big mother-hulking power plant at a big coal mine or dam for example. Natural gas is cheap and efficient to ship long distances, so that makes sense to me.
From your description KMS was doing laser implosion, a technique also studied at the national labs with some of the large lasers in the world of the time. The requirement for perfects spheres is key to it. High power lasers fire simultaneous from all directions. The energy causes the outermost layer to explode into plasma, and in reaction a shock wave travels inwards at the same time. If the object is spherical, these waves compress the core of the sphere to the necessary temperature and pressure for initiation.
The bubble implosion method has been discussed for many years; the first I heard of it was in a hallway chat with Dr. Forward about ten years ago. The first real test of it came just within the last couple years (Science 20020308 ‘Evidence For Nuclear Emissions During Acoustic Cavitation’, Taleyarkhan; “Evidence For Nuclear Reactions In Imploding Bubbles”, Bechetti; “To Publish Or Not To Publish”, Kennedy) I believe I wrote an article on it at the time. The researchers were from Oak Ridge and Rensselaer Polytechnic Institute, and there was much scoffing and posturing by other researchers at the time. I’d almost forgotten about it.
The bubble method works as follows: ultrasonics create bubbles in a fluid of deuterated acetone. The ensuing bubbles collapse at such high speed they form a shockwave that drives the deuterons into initiation conditions in thousands of very small regions.
The evidence in previous experiments has been neutron emission. As I said then and still say now, it is not clear to me how you could withdraw significant amounts of energy from this. The energy comes out in neutrons which have to then be slowed in a moderator; it is a normal heat engine. The problem is, you can’t raise the temperature of your working fluid or you destroy the ability for it to make liquid/vapour transitions… but if you keep your temperatures low, you get a low Carnot efficiency.
Unless they have some completely different trick up their sleeve (perhaps using D-He3 to get protons instead), I don’t see how to actually *do* anything with this.
Suggestions welcome… and no, I haven’t read the papers yet. I’m actually just in and recovering from a weekend fleadh (translation: drinking, trad music, drinking, chatting up women, more drinking, repeat until comatose)
Most of the works seems to have been done at the Oak Ridge National Lab in Tennesse and has been published in peer reviewed papers. I’m fairly confident that unlike Cold Fusion there is something to this. They have been replicating the process. That is the important thing.
That said, I agree with Dale getting from this experiment to a full scale useful generating device is going to be a tricky proposition.
The scale they are at now reqires statistical evidence to show something happened. That is tthey need sensitive detectors and lots of time to get a good signal to noise.
What this means is that the device nedds to be scaled up by a billion times a billion times a billion (very roughly) to get useful power output.
It’s far worse than scaling up. This is only experimental proof of an effect. I’ve not so far heard any suggestions as to engineering solutions to power extraction. I am not claiming none such are possible, only that I do not myself see away around some very difficult challenges, as I noted in my earlier discussion.
Dale,
I quite agree.
Plus there is no clue if net power output is even possible.
Right now the case is watts in and pico-nano-watts or less out.
The fact that the effect has such a low probability and that since the effect is localized (in the bubbles) means that making the apparatus larger will likely not improve the probabilities (as happens with nuclear reactors).
To improve the reaction rate bubble temperatures will need to go up. Perhaps because of the rate law involved a doubling of temperature may be all that is needed. But tthat may not be easy at all.
The fact that the effect is real will get a lot more minds working on it so that real progress is possible over a 10 to 15 year span.
OTOH magnetic confinement fusion has been just around the corner for decades, despite tens of billions invested.
At least in that case possible designs for a power reactor have been produced.
I also remember a few years back a very exciting paper from a U.S. group re. boron/hydrogen fusion which was going to produce direct electrical output without the need for turbines and without neutron contamination. Sadly it turned out that the scheme would never be net power generating because you couldn’t get more than 3 or 4 times gross power output which meant less than 1 net. Taught me to be sceptical about fusion claims in future!
OTOH, M Simon is being slightly unkind to the magnetic confinement people. Since work started, in the 50’s, by all relevant measures they have made advances by many orders of magnitude.
My two penn’orth: I think muon-catalysed fusion could be big one day. Andrei Sakharov was a proponent of this technique.
I’m not sure if the sonoluminescence technique is a simple heat engine. The power extraction in a conventional tokamak is via neutron absorption in a lithium coolant (this has the additional advantage of breeding tritium). These are fast neutrons and thus their ‘temperature’ (in a Boltzmann sense) is very high. Anything greater than 100 keV is considered a fast neutron.
There’s also an inertial confinement technique known as a gas-embedded Z-pinch. When I was at the Blackett Laboratory at Imperial College, they were constructing a Z-pinch in the basement. Apparently when the Marx generators (which were constructed from submarine batteries and about the size of a maisonette) were fired up, it was quite a sight to see. A million volts at a million amps for a few tens of microseconds. Yup, that’s Terawatts of power. One of the advantages of a Z-pinch is the dimensional quality of your fusing medium (a thread of frozen hydrogen) doesn’t have to be so high because the embedding gas evens out its radial expansion.
As an afterthought to my earlier post, I mentioned that, so far as I knew, cavitation bubbles contained a vacuum- which is why they can collapse so violently. If that is the case, how much deuterium would there be in a bubble? I don’t know offhand if normal vapor pressure measurements would apply to bubbles that exist so briefly. Presumably the vapor pressure over a surface is an equilibrium figure and would take some time to attain starting with a vacuum and a vapor pressure of zero.
I suppose the fact that they are getting some output indicates that there is some deuterium in the bubbles. However, there must be a tradeoff between the amount of deuterium in the bubble and the energy in the bubble collapse. More deuterium = slower and less energetic collapse.
Thoughts?
Not necessarily a vacuum but definitely a rarefaction. The contents of the bubble are the deuterated medium in gaseous form.
It is not at all hard to cause fusion at low levels. A uranium-based implosion weapon requires a neutron source, which is little more than a vacuum tube where deuterons are accelerated by a few thousand volts and run into others. In other words, its an electrostatic accelerator.
The fusion cross section is very low, the energy yield is microscopic, but fusion neutrons will come out of the thing.
As another poster mentioned, KMS Industries had already demonstrated the success of fusion implosion by 1974, and experiments in 1976 received over 30% return in “fast” neutrons when they used their Chroma laser system to initiate the burn. By 1988, KMS had produced densities over twice that of gold and had produced burn temperatures from between 5 to 10 million degrees. Then, suddenly the government was suing KMS, removing funding and replacing them with the research facility who made complaint against KMS, initially to start the DOE “investigations.” Patents, of course, are property of the government. As was mentioned, KMS was purchased, at least controlling interest, by oil interests (North Sea and Texas Transfer.) The fusion research portion of the company was then “spun-off” and no private stock was issued. The fusion patents, originally owned by KMS, are now owned by KMS, Fusion a privately owned organization.
Of course, oil interests have a great stake in not recognizing and even suppressing this technology but what is the motive of government and science in keeping this “quiet?”
The economy, of course for the government, since even the gold standard is shot to hell when gold is a byproduct of lead shielding and heat transfer, or using shielding of whatever substance you care to “build” or “seperate” and which you are able to do with a plentiful supply of neutrons. What standard is available for what then will be a completely outmoded “system?”
But, what about science? Notwithstanding the obvious, personal sinecures such “secrecy” would provide, why wouldn’t someone come forward and say, “Hey, they could have had the NIF finished 2 years ago, but now it won’t be until 2008, and what’s this talk about “success” in 2050 Bush said? We were getting more than 30% return with a squirt-gun in 1976, for God’s sake! And now it’s 2050? We can do this thing right now!!!”
I think it is because the strong force has been ignored and it can’t when the public becomes informed and realizes the importance of plasmas and the strong magnetic and electrical forces they generate, and of which fusion is a byproduct. It will take until about 2050 to save some face by slowly bringing the strong force into general relativity.
Just as an aside, notice the new photos of Saturn’s moon Phoebe. One of the craters is obviously not made from any “impact,” and many of the other craters appear more like “puddles” than impacts. Check this site out for some explanation of this type of phenomena and others equalling interesting and involving strong force theory in cosmology.
Holoscience.com
I guess you do not know what happend to KMS and Dr. Seigel. His company and reactor was seized by the government it was a government secret (fusion energy). Dr. Seigel requested a hearing before a senate committee to complain about this illegal seizure, but he died of a ‘heart attack’ before he could give his speech. His murder is a warnng to anybody planning to build a fusion reactor,