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I am super impressed at how forthcoming LPP was about the cathode cracking problems — the newsletter is very clear both about what the issue was, where things went wrong, and what they’re doing to fix it. I can’t think of any other company that would be willing to say “our president and chief scientist made an error that caused a sizeable problem”. I really do appreciate the enormous amount of transparency that LPP has always provided, and the fact that the company seems free of the PR and spin that so many other startups have.

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Andrew Palfreyman wrote: has anyone taken the trouble to do a serious economic quantification of the cost benefits of Focus Fusion? One has to include, for example, the mundane cost of getting the boron on-site.

Right, but you also get to exclude standard power plant costs for things such as turbines and generators, along with all their associated overhead (e.g., extra staff, extra space, etc.).

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You might find this chart helpful:

http://lawrencevilleplasmaphysics.com/sankey-diagram-focus-fusion-energy/

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Like most things, one of the larger costs for an FF generating station will be personnel, and the way to minimize that cost is to centrally locate multiple devices, and have those overseen by a small staff, rather to have many distributed small generation stations that each need their own staff.

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zapkitty wrote: it seems more likely that they’ll use MHD to tap the fusion products for enough energy to power the device itself… but still needing to have a separate steam cycle for net power output to the grid. If that’s the case then perhaps a more accurate phrasing would be “eliminating [em]some[/em] of the usual capital costs associated with neutronic fusion”

Once you need [em]any[/em] sort of steam-turbine-generator setup, that presumably wipes out almost all the capital savings, right? Sure, you might be able to get away with a smaller turbine and generator, but I would think the main cost is the physical plant and gear associated with [em]any[/em] sort of steam generation.

In other words, if they’re not fully direct generation, I’m not sure how they can claim that there is any significant capital savings.

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ikanreed wrote: Are you sure you meant He3+proton? I mean, there’s a lot about subatomic reactions I don’t understand, but isn’t it t+proton?

No, I meant (and wrote) “H3 nucleus and a proton”, which is also “tritium and and proton”.

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Unless I’m profoundly mistaken, the D-D reaction has two equally-likely paths: an H3 nucleus and a proton, or a He3 nucleus and a neutron. As far as I know, D-D -> He4 is not a reaction that occurs with D-D; the secondary reaction of D with the H3 produced can generate He4, but it will also produce another neutron.

So in general, D-D fusion is not at all aneutronic.

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mchargue wrote: What other technology might replace capacitors in this application?

How about a focus fusion device? When a FF fires, would the pulse it produces be short enough to get another FF to fire? If so you could daisy chain the suckers, and just need a set of caps to get things rolling. It’s not perpetual motion exactly, but…

🙂

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Joeviocoe wrote: Worst case (assuming monthly replacement without recycling electrodes):
A 5MW reactor will produce 700 MWh of electricity each month, but consume 40 kg of Beryllium..

I very much doubt the electrodes will evaporate over a kilo of beryllium a day into the chamber.

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And, to address the spirit of the original question, the annual production of beryllium in 2011 was 400 metric tons. (Interestingly, that source also indicates that production may increase to meets the needs of ITER, so yet another fusion connection.)

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I believe the tungsten is just for the current round of tests. The intent is to make the production electrodes out of beryllium, as it is relatively transparent to x-rays and thus won’t heat up as much and absorb energy that would be captured by the “onion” and produce power.

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I believe the intent of LPP is to use decaborane, B10H14, which is a solid at STP that sublimates into gas at a moderate vacuum. It is nasty stuff, though, as it is a neurotoxin. You really don’t want to handle it if you don’t know what you’re doing.

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I think here’s the key point:

An experiment at the National Ignition Facility of Lawrence Livermore National Laboratory is the first time in history that a human-created nuclear fusion reaction has been proven to create more energy than [em]the amount absorbed into the reaction itself[/em].

In other words, this is not “more energy than was used”, merely “more energy than was [em]absorbed[/em]”. Lasers are not super-efficient, and much of the energy put into them comes out as heat, so this estimation does not include that, or any other inefficiencies. This is not “theoretical breakeven”, at least not as I’ve seen it defined.

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DPF is designed to be aneutronic, so you don’t want to be generating neutrons from alpha collisions.

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But this wouldn’t be the first claim of theoretical breakeven by a fusion device, would it? Haven’t other teams made claims of theoretical breakeven?

And whatever the scientific achievement, as I said I don’t know for (savvy) investors how important D-T would be. The issue is making a practical generator, not pure scientific research. We already know how to get fusion reactions to produce more energy than they consume, i.e., thermonuclear bombs. The practical concern is getting usable energy out. That’s the goal of FF, and I don’t know that a theoretical D-T breakeven would get the LPP team that much closer to that goal. Of course, I might be mistaken.

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