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Ivy Matt wrote: they claim to be generating a megawatt of power from 40 watts of input power. That’s scientific breakeven at least

Only if that 40 watts includes the power necessary to produce the muons, which (as I understand it), would entail a major and fundamental breakthrough in physics.

In other words, I’m extremely dubious.

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asymmertic_implosion wrote: It’s not 100% clear why, but a plasma focus seems to work better with individual cathode rods. People speculate that some of the gas between the anode and the cathode needs to be pushed out while others cite debris as the reason.

If the problem is gas circulation, then one presumably could just weld the cathode rods on the inside of a series of rings, which would make the assembly one piece while still allowing circulation.

I get the sense that there is a lot of interesting testing to be done on cathode parameters.

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Given that symmetry in the physical geometry of the electrodes appears to be important, is there any reason that the cathodes have to be separate rods? A solid piece, with projections to guide the plasma filaments, would mean that one never had to worry about individual cathode alignment. Is it necessary to have empty space between the individual cathode rods?

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Burning hydrocarbons produce their own problems, even if the source of those hydrocarbons is carbon-neutral. Soot, NOx, even unburned vapour are all not-great-things health-wise.

Also, if we get FF, then the possibility of relatively compact generation makes the current existence of a liquid fuel distribution system rather moot, as your source of motive power can be located anywhere, without any need to hook into a larger distribution system. (Indeed, the military may be the first to go largely electric, as it is far cheaper to plop down a shipping-container-sized FF generator than ship in tons of fuel or build a hydrocarbon generator that requires a lot of water.)

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Companies that provided whale oil were also large. Companies that provided coal-based home heating were also large. It doesn’t matter how big you are if consumers aren’t buying your product, and there is only so much that economic and political power can do to ensure that consumers buy your product.

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A thousand bucks for the hearsay of an unnamed source? Yeah, right…

That said, it does kinda sound like Rossi, which rings even more alarm bells.

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That is indeed outstanding news — it looks like things are beginning to move along at a faster clip.

Is there any news on when we might expect pB11 shots?

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zapkitty wrote:

As I understand it, aneutronic fusion wouldn’t be much use for cleaning up fission waste, since what you want to do with such waste is transmute the problematic nuclei, which entails a neutron source.

Nope… neutrons can be generated without a neutronic fusion power source.

Right, my point was not that all neutron sources were fusion-based, but that aneutronic fusion is, by definition, [em]not[/em] a neutron source, and neutrons are what is needed.

In fact anyone can generate neutrons. All you need is electricity.

Yes, but aneutronic fusion does not have some special advantage in radioactive waste transmutation [em]beyond[/em] producing cheap power. There is nothing [em]inherent[/em] in the aneutronic fusion process that makes it a good way to clean up radioactive waste.

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As I understand it, aneutronic fusion wouldn’t be much use for cleaning up fission waste, since what you want to do with such waste is transmute the problematic nuclei, which entails a neutron source.

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“Aneutronic” refers to the nature of the fusion reaction, namely that it produces no (or, more accurately, very few) neutrons. This characteristic is in principle orthogonal to the method used to get the nuclei to fuse (although aneutronic reactions generally require higher energies to cause fusion).

(This is all my understanding — someone else may be able to correct any errors I’ve made.)

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Speaking of media coverage of GF, here is a terribly researched article by the CBC on someone worried about the safety of the research.

I would think that the real safety issue with GF is the use of hundreds of pneumatic rams whacking a big sphere of liquid metal — if anything fails there mechanically, one could have a real mess in a real hurry.

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I think that cathode erosion is likely to be much less of a problem than ensuring that 200 pneumatic pistons all fire in with nanosecond precision continually day after day, as in the case of GF.

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Presumably the most appropriate metric in the end is (likely) cost per kilowatt/hour of generated electricity. That’s what really ultimately matters, and that captures all the “overhead” that tokamaks and other similarly-sized approaches have (e.g., large capital investment, dealing with radiation from neutronic reactions, inefficiencies in using radiation to heat fluid to boil water to create steam to drive turbines to turn generators, etc. etc. etc.).

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Steven Sesselmann wrote: Look at some of the rediculous projuect that have been funded, such as LIGO and the LHC and soon ITER, where governments have sunk billions into the project, only to be told in a billion page document how the negative outcome of the experiment was a great success, and that not finding gravity waves or Z bosons proves that we had it all wrong.

That’s precisely how good science works, by ruling out possibilities. It’s silly to say that LIGO and LHC are failures because they did not confirm existing theories (and it is way too early to say that LHC is a failure even by that criterion).

You might as well say that the Michelson-Morley apparatus was a failure because it didn’t demonstrate the luminiferous aether.

I also think it is hugely important to distinguish between basic science and more applied or practical science. LIGO and LHC are designed to answer fundamental questions about the universe, whereas ITER is designed with a far more practical final goal, to produce fusion energy. Sure, it involves a lot of theoretical physics to do so, but the ultimate aim is very pragmatic. To me it makes far more sense to criticize such practically-targeted projects when they are spending huge amounts of money with no results, since such negative outcomes are antithetical to the final goal, unlike in basic science, where a null result can be hugely informative.

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I’m all for fusion, but I really question the utility of NIF for practical generation (to me it’s a scam, a nuclear weapons stockpile assurance program sold as fusion research). More generally I think that approaches like DPF and FRC and Polywell are far more likely to produce practical powerplants. So while I understand that, to some extent, a “sinking tide lowers all boats”, I don’t know that I’m terribly upset that the giant fusion projects are having tens of millions cut from their budgets of hundreds of millions.

And yes, the tar sands are an environmental nightmare.

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