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Revamped German stellarator should run longer, hotter and compete with tokamaks

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Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#41

Post by moogly »

NKosmatos wrote: post #28

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

> We’re still a few years away from having them in actual power plants

I admire your optimism. I'd say half a century, if things go well, but I'm not convinced fusion will ever be economically feasible.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#42

Post by imglorp »

Tuna-Fish wrote: post #32
ak217 wrote: post #23

Earlier quoted context omitted.

By capturing neutrons (which, not being charged, escape the magnetic confinement continuously as the reaction goes on) with a moderator blanket which is then cooled with water/steam. How to keep the blanket from quickly degrading and becoming nuclear waste seems to be an open problem (not too different from what goes on in fission reactors though) https://en.wikipedia.org/wiki/Fusion_power#Energy_capture

> How to keep the blanket from quickly degrading and becoming nuclear waste seems to be an open problem Not really. Most reactors plan to also use the neutrons to breed the tritium fuel for the reactor, so the blanket would consist of liquid metallic lithium. The only products from neutrons reacting with lithium nucleii (either 6 or 7) are He-4 and tritium. The open problem is how to safely maintain the reactor-facin…

It looks like all the isotopes of LI are very short lived. Is the problem some of the daughters, or perhaps the Fe and C in the steel that are the problem?

https://www.thoughtco.com/lithium-isotopes-radioactive-decay...

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#43

Post by simonebrunozzi »

moogly wrote: post #41
NKosmatos wrote: post #28

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

> We’re still a few years away from having them in actual power plants I admire your optimism. I'd say half a century, if things go well, but I'm not convinced fusion will ever be economically feasible.

I think that 50 years is a reasonable timeframe to give fusion the possibility of delivering results. But I agree with you, it's pretty much impossible that anything will come out of fusion in the coming 10-15 years, despite the publicity we keep hearing lately.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#44

Post by ajross »

NKosmatos wrote: post #28

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

> ongoing/coming energy crisis

This has been IMHO inappropriately hyped. We have an expected gas shortfall in Europe due to the mess made by one rogue actor (though Putin hasn't shut the pipes off yet, The existing price shocks are all speculative!). Petroleum production is fine. Gas production outside of Europe is fine. Existing interests in those industries have been exploiting the resulting price shocks (which are not the same thing as a crisis) to try to drive public policy decisions in their direction.

We've been here before in the 1970's when rogue actors tried to exploit their production capacity for political gain. It sucked, but we didn't get fusion out of it then either.

Frankly it's not even the first time we've had a supply shortfall. People tend to forget this, but we ran out of oil in the late 90's too! Turns out, there was lots more oil available at higher price points.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#45

Post by ben_w »

DennisP wrote: post #7
wincy wrote: post #2

This has to be the most opaque title I’ve ever seen on Hacker News. For anyone wondering, this is about a potential development in cold fusion reactors.

Hot fusion, not cold fusion. It runs at a hundred million degrees C. Hot fusion is a well-known process that powers the sun. Cold fusion is a supposed low-temperature process that most scientists doubt is real, and if it is real we don't understand the physics of it.

Sometimes I like to say that the 15 million kelvin core of the sun is actually a cold fusion reactor, on the grounds that fusion within it is dominated by quantum tunnelling, rather than classical kinematics, overcoming the Columb barrier.

Also like to surprise people with a fusion process that works at temperatures in the single-digit kelvin range: https://en.wikipedia.org/wiki/Muon-catalyzed_fusion

But yes, the linked reactor isn’t that, and the thing commonly referred to as “cold fusion” probably isn’t real.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#46

Post by wincy »

irjustin wrote: post #18
wincy wrote: post #2

This has to be the most opaque title I’ve ever seen on Hacker News. For anyone wondering, this is about a potential development in cold fusion reactors.

How did you get cold anything from this?!

I dunno I thought hot fusion was a waste of time unless you’re doing it inside of a star. So I just assumed it was about cold fusion.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#47

Post by ClumsyPilot »

sidkshatriya wrote: post #39
GordonS wrote: post #29

Earlier quoted context omitted.

I agree. If we were able to eventually miniaturise fusion reactors, they would be incredible for space flight. Back on Earth, if they could be made safe enough, maybe we could even use them to run container ships?

With all the fast neutrons emanating from a fusion reactor (and the heavy confinement that it requires) I don't think a container ship would be a safe enough environment (threat of disaster at sea, constantly jostling which might affect plasma stability etc.). But yes, there is a potential for a lot of space applications and other things we haven't thought of yet.

what kindof disaster could be relevant in this context? If the ship sinks, the minor radioctivity of a shutdown reactor will not be relevany

Technically, container ships are enormous and can use ballast water for shielding. I can't judge the ecobomics ofcourse

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#48

Post by okasaki »

moogly wrote: post #41
NKosmatos wrote: post #28

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

> We’re still a few years away from having them in actual power plants I admire your optimism. I'd say half a century, if things go well, but I'm not convinced fusion will ever be economically feasible.

The UK government plans to have a fusion power plant on the grid by 2040

https://assets.publishing.service.gov.uk/government/uploads/...

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#49

Post by Maken »

moogly wrote: post #41
NKosmatos wrote: post #28

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

> We’re still a few years away from having them in actual power plants I admire your optimism. I'd say half a century, if things go well, but I'm not convinced fusion will ever be economically feasible.

It feels like fusion energy is perpetually 50 years away.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#50

Post by Retric »

Maken wrote: post #49
moogly wrote: post #41

Earlier quoted context omitted.

> We’re still a few years away from having them in actual power plants I admire your optimism. I'd say half a century, if things go well, but I'm not convinced fusion will ever be economically feasible.

It feels like fusion energy is perpetually 50 years away.

Minimal investment means minimal progress. ITER was basically a Regan/Gorbachev project from 1985 that’s still not built yet. It’s JET’s the current largest device was completed in 1983. Real progress has been made, but the major projects have been extremely conservative by necessity.

Early designs for ITER where for a larger device that would have actually produced electricity though not cheaply enough to be economically viable, but it got scaled way down.

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