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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

#31

Post by dale_glass »

sneak wrote: post #26
arghandugh wrote: post #20

Earlier quoted context omitted.

You will not live long enough to see commercial fusion power, and your children will not live long enough to see a complete end to thermal coal.

Tossing out your opinions as fact doesn't do much to win hearts and minds, or educate us bystanders to the basis for your point of view. Presumably your comment is either to persuade or to inform; it does neither. I'm very curious about this field and its future, do you care to try again?

I'm a different person, but I tend to agree.

ITER began building in 2013, first plasma is expected for 2034. DEMO is expected to start in 2040.

So, ITER is taking an estimated 20 years. It's being built for a reason, so I imagine follow-ups want to wait to see how that shakes out. So certainly, DEMO needs to start a few years after ITER is finally done.

Then DEMO isn't a production setup either, it's going to be the first attempt at a working reactor. So let's say optimistically 20 years is enough to build DEMO, run it for a few years, see how it shakes out, design the follow-ups with the lessons learned.

That means the first real, post-DEMO plant starts building somewhere in 2060. Yeah, fair to say a lot of the here present will be dead by then, and that'll only be the slow start of grid fusion if it sticks at all. Nobody is going to just go and build a hundred reactors at once. They'll be built slowly at first unless we somehow manage to start making them amazingly quickly and cheaply.

So that's what, half a century? By the time fusion gets all the kinks worked out, chances are it'll never be commercially viable. Renewables are far faster to build, many problems are solvable by brute force, and half a century is a lot of time to invent something new in the area.

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

#32

Post by BizarroLand »

arghandugh wrote: post #19
BizarroLand wrote: post #17

Earlier quoted context omitted.

Real talk, the point is not that whatever system is first past the post for fusion becomes the gold standard and fills the planet. The issue right now is cracking the code. Once that is done, performance gains and miniaturization can take place. Fusion can work on lots of things. Its possible that a fusion system the size of a car could be made within 25 years of the code being cracked that would power a house, or th…

You’ve disputed nothing I’ve said and unless a dramatically higher temperature fusion reaction that does not generate a neutron flux is achieved, it will generate radioactive waste as a matter of factual physics. Thank you though!

I mean, yes, you're right, but it's not a permanently radioactive waste.

Quote:

A fusion power plant produces radioactive waste because the high-energy neutrons produced by fusion activate the walls of the plasma vessel. The intensity and duration of this activation depend on the material impinged on by the neutrons.

The walls of the plasma vessel must be temporarily stored after the end of operation. This waste quantity is initially larger than that from nuclear fission plants. However, these are mainly low- and medium-level radioactive materials that pose a much lower risk to the environment and human health than high-level radioactive materials from fission power plants. The radiation from this fusion waste decreases significantly faster than that of high-level radioactive waste from fission power plants. Scientists are researching materials for wall components that allow for further reduction of activation. They are also developing recycling technologies through which all activated components of a fusion reactor can be released after some time or reused in new power plants. Currently, it can be assumed that recycling by remote handling could be started as early as one year after switching off a fusion power plant. Unlike nuclear fission reactors, the long term storage should not be required.

https://www.ipp.mpg.de/2769068/faq9

Basically, whatever containment vessel becomes standard for the whole fusion industry would need probably an annual cycle of vessel replacements, which would be recycled indefinitely and possibly mined for other useful radioactive byproducts in the process.

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

#33

Post by robocat »

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…

They should also have put fusion bombs on the graph?

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

#34

Post by dale_glass »

It should be noted that "breakeven" is often misleading.

There's "breakeven" as in "the reaction produces more energy than put into it", and there's breakeven as in "the entire reactor system produces more energy than put into it", which isn't quite the same thing.

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

#35

Post by hinkley »

DennisP wrote: post #16
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…

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…

I was trying to work out a joke about buying better lasers off of alibaba but it seems that despite being 30 years old they're still orders of magnitude beyond off the shelf options.

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

#36

Post by hinkley »

UltraSane wrote: post #22
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…

It was never intended to be a power plant but it was hoped that it would achieve a net gain fusion reaction for the first time. This turned out to be a lot harder than expected.

NIF has achieved net power, right? But only if you ignore the massive, massive power losses in converting electricity to feed energy into the system.

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

#37

Post by twothreeone »

sam wrote: post #14
CGMthrowaway wrote: post #13

Earlier quoted context omitted.

If ITER is where it's at why are we building commercial scale tokamak? https://en.wikipedia.org/wiki/Commonwealth_Fusion_Systems

Companies like Commonwealth Fusion Systems are an example of those utilizing high-temperature superconductors which did not exist commercially when ITER was being designed.

ITER uses HTSs, just not for the coils:

> The design operating current of the feeders is 68Ka. High temperature superconductor (HTS) current leads transmit the high-power currents from the room-temperature power supplies to the low-temperature superconducting coils 4K (-269°C) with minimum heat load.

Source: https://www.iter.org/machine/magnets

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

#38

Post by __MatrixMan__ »

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…

Nothing about the NIF looks like a power plant to me. It's like the laser weapons guy and the nuclear weapons guy found a way to spend giant piles of money without having to acknowledge the weapons angle.

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

#39

Post by robocat »

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…

> phony baloney jobs

I looked hopefully at the HR report https://www.iter.org/sites/default/files/media/2024-11/rh-20... to see if there was some sort of job categorisation - scientist, engineer, management. Disappointingly scant. PhD heavy. Perhaps the budget would be more insightful.

"Execution not ideas" is a common refrain for startups.

I wonder how much of the real engineering for ITER is occurring in subcontractors?

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