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Focus Fusion On Google Tech Talks
Henning Burdack writes "Eric Lerner talks on Google Tech Talks about Focus Fusion, which would be a much cheaper and more feasible technology as a fusion energy source than any other current approach, based upon the dense plasma focus device. The technology will use hydrogen-boron fusion with direct induction of ion energy and photovoltaic conversion of x-ray emission, obviating the need of a steam-cycle and thus resulting in higher efficiencies. High temperatures of 1 billion Kelvin (100 keV) have been reached years ago. It only needs $2 million in funding and two years of research for a proof of concept, and maybe four more years for a prototype with positive energy output. In contrast to other fusion efforts it utilizes the natural instabilities of plasma instead of fighting them. Focus Fusion has been discussed on Slashdot before, and a patent application is also available, going a bit more into detail."
I looked at the wiki history page on aneuronic fusion, and found that wiki poster 'elerner' had been banned from further edits.
Now here he is introducing a project that requires millions of dollars in funding.
Ok, I'm a bit cynical, but this does look like a possible conflict of interest to me.
I don't know about this guy's background, but so far (still watching) he hasn't said anything crazy that signifies obvious crack-pottery. There's been o zero-point energy nonsense, and he's using standard terminology to explain things in a way that would make sense to someone with a little background in the subject. The new bit seems to be clever use of plasma instability to get the energy density required to initiate fusion. I'm not a plasma physicist (just particle physics), so I can't critically evaluate the details of the method. So far I'd believe this is plausible, but I don't know enough to be willing to give this guy any money.
And for gosh-sakes, fix the article summary. keV = kilo electron volts, not Kelvin!
This is one of a number of devices that can produce some fusion, but don't put out more energy than is put in. Forty years ago, this idea looked more promising. There was a fusion demo of a "plasma pinch" fusion system at the General Electric pavilion of the 1964 World's Fair. So far, no variation on this scheme has come even close to breakeven.
agreed. The number is suspiciously low. It is small enough for private funding, however, which puts it deep into possible scam territory. If this has been around for a while and the guy is publicly looking for money it implies he has already been refused for a bunch of grants. If there are no refused grant applications, then it gets more creepy. The patent may be another sign.
IMHO anyone interested in investing in this guy who is not a university or reserch institute should be extremely careful. Like put a radio ankle bracelet on him careful.
http://video.google.com/videoplay?docid=1996321846673788606
In a proper and decent world, men like Robert Bussard would be heroes to our children, and household names that have high schools named after them... his concept of a fusion ramjet, the Bussard Ramjet, from Known Space and other places... is still the only realistically viable idea for intersteller travel...
IANANP... would love someone who is to break this video and it's ideas down... would it work?
peace
Years later, a doctor will tell me that I have an I.Q. of 48, and am what some people call "mentally retarded".
He said it was crackpot. I didn't try to get him to go into details, but he basically mentioned the same stuff you did - stellarators, etc. What's more, there is the crack-pottery in the clip about how all the people in the field are in a conspiracy to deny his idea funding. I know these people - you might find some or even a majority who would be so unscrupulous, but nowhere near enough to maintain such a conspiracy. So, I would tend to think that you're right.
Basically, this guy is probably guilty of exactly what he accuses the rest of the fusion community of - he's fixated on his idea. He apparently won funding from the navy, so there's a chance his group could prove me wrong, and I hope that they do, but I doubt it.
High temperatures is not the problem, D-T fusion only requires some 16keV, and this is easily achievable using rather cheap voltage source. However, to get more energy out than you get in, you must ensure that this energy stays in the plasma and causes fusion, rather than just radiating right out of it again. In practice this means you need a high density and large confinement time ( basically a measure of how rapidly the plasma loses energy ).
Now, the issue with fusion using fuels with higher atomic number than hydrogen is that the plasma will contain much more electrons, and this dramatically increases the amount of energy lost as bremsstrahlung when the electrons collide with the nuclei (the increased mass of the nuclei also plays a part ). Direct conversion of X-rays could theoretically help alleviate this as it would allow you to feed the lost energy back into the plasma, problem is, photo-voltaics have nowhere close to 100% efficiency.
Aneutronic fusion has advantages. You don't have to worry about neutron damage to the reactor vessel. However, when you look a bit closer at it, this isn't such a large advantage after all, because the neutrons are actually quite useful in that they deposit the energy over a quite large volume when they are being absorbed, reducing the stress caused by heating in the device. If it wasn't for the neutrons you would see most of the heat deposited in a comparably thin layer of the plasma-facing compounds. The counter for this is that aneutronic fusion releases the energy as charged particles, potentially allowing for directly converting the energy into electricity.
Basically, what this whole thing boils down to, is if you are able to achieve sufficiently good direct-conversion efficiency to counteract the increased X-ray losses due to the higher atomic numbers associated with aneutronic fusion. This is why you often see claims of breakthroughs in aneutronic fusion together with claims of either a non-maxwellian velocity distribution or some other remarkable way to reduce X-ray losses. A plasma with a maxwellian velocity distribution cannot sustain aneutronic fusion without being either very large and dense (to re-capture the X-rays) or by somehow capturing the lost X-rays after they leave the plasma and feeding the energy back into it.
For a non-maxwellian velocity distribution your problem is that even at optimal energies a collision is much more likely to scatter the ions than it is to cause fusion, and restoring the non-maxwellian velocity distribution will require energy (no, you don't get to violate the second law of thermodynamics I'm afraid ). For capturing X-rays your problem is to achieve a good enough conversion efficiency to make up for the dramatically increased X-ray losses.
With the exception of a few unconfirmed claims, nobody has been able to resolve the above problems (thou Bussard was quite vocal about his polywell device ) and this is pretty much why modern fusion power research uses D-T fusion. It gives the highest amount of energy for the lowest temperature and X-ray losses, at a maxwellian velocity distribution.