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Progress toward fusion energy gain as measured against the Lawson criteria

fusionenergybase.com

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Re: Progress toward fusion energy gain as measured against the Lawson criteria

#101

Post by chuckleMuscle »

mapt wrote: post #97

Anyone have any idea where First Light Fusion's third machine fits into this? The idea of using literal guns (gunpowder, then light gas gun, then coil gun) to impact projectiles against each other seemed like it was probably ludicrous, but I haven't seen any critical media or numbers yet.

FLF's own numbers on this are given in a white paper [1, fig 7.]. Note the "fusion measured" datapoint used a gas gun, rather than Machine-3, as the driver... [1] https://firstlightfusion.com/wp-content/uploads/2024/08/firs...

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#102

Post by tim333 »

0xbadcafebee wrote: post #80

Amazing! Commercial fusion energy is only 30 years away. (it's been 30 years away for 50 years already, but as long as I'm not dead 30 years from now, it's still a good investment...)

Or maybe 10 https://news.mit.edu/2024/commonwealth-fusion-systems-unveil...

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#103

Post by myrmidon »

pfdietz wrote: post #28
cyberax wrote: post #6

Earlier quoted context omitted.

The ITER is in development hell. Mind you, it's not useless! It produced a TON of very useful fusion research: neutral beam injectors, divertors, construction techniques for complex vacuum chambers, etc. At this point, I don't think it's going to be complete by the time its competitors arrive. One spinoff of this is high-temperature superconductor research that is now close to producing actually usable high-TC flexib…

ITER doesn't use high temperature superconductors. It uses niobium-tin and niobium-titanium low temperature superconductors in its magnets. ITER has been criticized since early days as a dead end, for example because of its enormous size relative to the power produced. A commercial follow-on would not be much better by that power density metric, certainly far worse than a fission reactor. There is basically no chance…

> I call things like ITER "Blazing Saddles" projects. "We have to protect our phony baloney jobs, gentlemen!"

I think this is overly harsh and somewhat unfair. You could make the same argument that anything operating in a regime similar to the Chicago Pile 1 could never be an economical reactor nor a bomb, but that does not mean skipping that particular development step is viable.

As far as fusion reporting goes, articles are at least somewhat consistent on the fact that ITER is a pure research project/reactor, while every 10-man fusion startup is being hyped up beyond all reason even if there is not even a credible roadmap towards an actual reactor in the 100MW range at all.

Personally I don't see fusion being a mainstream energy source (or helpful against climate change) in this century at all and maybe never, but ITER (even with all the delays) is at least an honest attempt at a credible size, and being stuck on older technology is an unfortunate side-effect of that.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#104

Post by trollbridge »

willis936 wrote: post #98
russdill wrote: post #92

Earlier quoted context omitted.

It's always confused me a bit. It's not like if you put 10kWh into the reactor, that 10kWh goes away. You still lose a significant fraction of it in inefficiency of the cycle but it still goes towards heat which can be used to heat steam and turn a turbine. iirc, you can get about 4kWh back. On the other side of the coin, if you put 10kWh in and get 10kWh of fusion out, that's 20kWh to run a steam turbine, which nets…

Cars are a good analogy. You wouldn't talk about miles per gallon until you have an engine that idles. Humans are in the engine building phase.

That’s a good analogy - and the situation right now is trying to make a car that doesn’t use its entire tank of fuel before it arrives at the service station.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#105

Post by numb7rs »

CGMthrowaway wrote: post #15

I heard that NIF was never intended to be a power plant, not even a prototype of one. It's primarily a nuclear weapon research program. For a power plant you would need much more efficient lasers, you would need a much larger gain in the capsules, you would need lasers that can do many shots per second, some automated reloading system for the capsules, and you would need a heat to electricity conversion system around…

From my time in fusion research circles, you're correct, but it's also not a simple "weapons or energy?" question. It could only have ever been a pure research facility. At the time of design, the physics wasn't certain enough to aim for net energy gain. Where the weapons research came in is in the choice of laser focus. Instead of "direct drive", where the lasers directly strike the fusion fuel, NIF lasers strike the inside of a Hohlraum, which produces X-Rays that then heat the fuel. X-Ray opacity is an important topic in nuclear weapons research.

Bear in mind that I wasn't directly involved, and this my impression picked up from conversations during my time in fusion research, which was about 10 years ago.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#107

Post by myrmidon »

greenavocado wrote: post #43
sneak wrote: post #24

Earlier quoted context omitted.

What's the ROI on that versus current and near-term expected pricing for solar+storage? Is fission getting safer/cheaper at the same rate that solar and batteries are?

I wonder if it would make sense to make ultra heavy spent nuclear fuel into gigantic flywheels for short-term grid energy storage

No. Because flywheels are not limited by material density, they are limited by centrifugal force.

High density is actively bad, you want to maximize strength and minimize density for flywheel designs, and this makes you much more likely to end up with low density composites (rather than high density tungsten alloys or somesuch).

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#108

Post by pfdietz »

myrmidon wrote: post #103
pfdietz wrote: post #28

Earlier quoted context omitted.

ITER doesn't use high temperature superconductors. It uses niobium-tin and niobium-titanium low temperature superconductors in its magnets. ITER has been criticized since early days as a dead end, for example because of its enormous size relative to the power produced. A commercial follow-on would not be much better by that power density metric, certainly far worse than a fission reactor. There is basically no chance…

> I call things like ITER "Blazing Saddles" projects. "We have to protect our phony baloney jobs, gentlemen!" I think this is overly harsh and somewhat unfair. You could make the same argument that anything operating in a regime similar to the Chicago Pile 1 could never be an economical reactor nor a bomb, but that does not mean skipping that particular development step is viable. As far as fusion reporting goes, art…

I don't think it's unfair at all. And I don't see ITER as an "honest attempt", far from it.

The initial cost figures for ITER were obviously deliberate lies. When the true costs inevitably came out (after commitment had been made) this led to alternative approaches being canned. ITER has done grievous damage to fusion as a field, in a way eerily similar to how the Space Shuttle and ISS have done damage to NASA.

The true purpose of ITER wasn't to achieve fusion or push forward fusion; it was to preserve funding until those making the decisions had retired. If this required sacrificing long term goals, like actually delivering competitive energy (or, really, delivering anything at all), so be it.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#109

Post by Calwestjobs »

cyberax wrote: post #73
pfdietz wrote: post #68

Earlier quoted context omitted.

> ITER is NOT designed for power generation. It's essentially a lab experiment to see how plasma behaves in magnetic confinement and test various technologies. That's the go-to excuse. But if you look at DEMO, it's power density is not enormously greater. ITER is so far out of the running that DEMO (or PROTO, etc.) will be too. We're learning a great deal about something that's largely irrelevant.

DEMO concept sketches are completely obsolete at this point. It's not going to look anything like this. They're based on the state-of-the art from about 2005. Since then, a lot of improvements happened. A more realistic power plant design is going to use a thinner center column (because of better superconducting magnets), resulting in a smaller cryostat volume. Possibly high-TC magnets. It can also be made more compa…

misunderstanding about ITER what you some people doing is that it is just one thing, it is not.

ITER is not only facility in france it is multitude of manufacturing capabilities all over the globe which build parts for ITER and all future power plants.

Re: Progress toward fusion energy gain as measured against the Lawson criteria

#110

Post by bbatha »

boxed wrote: post #91
DennisP wrote: post #16

Earlier quoted context omitted.

It's an experimental facility. Yes, a power plant would need much more efficient lasers, but NIF's lasers date back to the 1990s, equivalent modern lasers are about 40X more efficient, and for an experiment it's easy enough to do a multiplication to see what the net result would have been with modern lasers. Modern lasers can also repeat shots much more quickly. Power gain on the capsules appears to scale faster than…

From what I understood, laser fusion needs laser efficiencies not just 40x better than what NIF uses, but like 3 or 4 orders of magnitude more efficient than the state of the art. Seems like a non-starter.

Everything fusion reactor design needs similar gains in some part of the stack outside of the fusion parts to make it a viable power source: tokamaks need magnets to be orders of magnitude better, the lining for the reactors needs to last for much longer, the whole steam conversion mess, etc.
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