11 ms·
Revamped German stellarator should run longer, hotter and compete with tokamaks
- wincy 4y agoThis 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.
- Jabbles 4y ago> cold fusion This isn't "cold".
- trebligdivad 4y agoThere's nothing cold about this.
- throwawayben 4y agoStandard (hot) fusion, not cold fusion. Having read a few articles previous on fusion, I'm familiar with the words tokamak and stellarator, so it was obvious to me that it was about fusion from the title. I wonder how many other titles you would consider opaque if you didn't happen to know the terms?
- DennisP 4y agoHot 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.
- ben_w 4y agoSometimes 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 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.
- irjustin 4y agoHow did you get cold anything from this?!
- wincy 4y agoI 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.
- detritus 4y agoMore opaque than every nth HN title referring to some cutely-monikered code framework that presses all the wrong mental buttons in those oblivious to its nature? Surely not.
- EamonnMR 4y agoSplark: a new phlinto framework built in blenk. And the thread is just Blenk fans arguing with Fobl fans.
- phist_mcgee 4y agoAs a fan of Fobl and their work on Spoogum, i'm not sure you would call it 'arguing' more sharing the obvious downsides of the dinglepop pipeline when combined with the grumpkin anti-pattern.
- amacbride 4y agoMeh. This was all solved decades ago with the turbo encabulator.
- hotpotamus 4y agoOthers are pointing out that this is (very) hot fusion. But I'd just say that if you know the first thing about fusion, the title is actually very simple, ie, stellarators and tokamaks are competing designs for magnetic confinement fusion. Of course, no one is born knowing anything about nuclear physics, and it's not really a casual subject of conversation, so there might be a lesson here that people could take about writing in domain specific jargon and how inaccessible it is for outsiders.
- kQq9oHeAz6wLLS 4y agoAnd if you know nothing about fusion, the title seems to be crafted of made up words. But if you take one glance at the comments, it becomes clear. So I guess the title was sufficient to pique my interest, which, after all, is the purpose of a title.
- dleslie 4y agoForgive my ignorance; what with all the effort made to isolate the exceedingly hot plasma from connecting with any surface, what are the plans to extract the heat in order to generate power?
- amelius 4y agoSince the plasma runs hotter than the Sun, and the magnetic field cannot confine photons, my guess is that the hull will become insanely hot, and you could use it to drive a steam engine.
- dleslie 4y agoAh interesting, so then the coolant for the shielding is also the means to power a generator.
- pfdietz 4y agoThis would be for DT fusion, so most of the energy would come out as neutrons. And it would face the same showstoppingly bad volumetric power density as tokamaks, because of limits on that energy flow through the surface of the reactor.
- sidkshatriya 4y ago> And it would face the same showstoppingly bad volumetric power density as tokamaks, because of limits on that energy flow through the surface of the reactor. I do think it is worth persevering though. The future of energy is Solar/Wind but Fusion should not be ignored. It is one of Nature's fundamental processes. Mastering fusion could turn out to be useful in ways we cannot possibly fathom at the moment right now.
- GordonS 4y agoI 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?
- homarp 4y agohttps://www.energy.gov/science/doe-explainsstellarators https://www.energy.gov/science/doe-explainsstellarators A stellarator is a machine that uses magnetic fields to confine plasma in the shape of a donut, called a torus. Over tokamaks, the other main technology that scientists are exploring for fusion power, stellarators require less injected power to sustain the plasma, have greater design flexibility, and allow for simplification of some aspects of plasma control. However, these benefits come at the cost of increased complexity, especially for the magnetic field coils.
- snovv_crash 4y agoStellerators aren't really in a torus, they are in a weird fractally twisted torus, sort of like a many-twisted Mobius strip. You really need to see a picture to understand.
- Bombthecat 4y agoI would say,it's like a roller coaster in a donut?
- snovv_crash 4y agoSort of, except the donut isn't necessarily a perfect torus, it can have spirals in the extrusion path as well.
- snarfy 4y agoIf a tokamak is a donut, then a stellerator is a French cruller.
- jobstijl 4y agoIn france they are building a next privately founded stellerator which seems intresting. https://stellarator.energy/ https://stellarator.energy/
- ncmncm 4y agoIt ought to interest securities fraud investigators, anyway. Anyone else, not so much.
- jobstijl 4y agoAny specific reasons why you think its fraud?
- ncmncm 4y agoEverything needed to go from Q > 1 to actual electric power is nonexistant, not even being worked on, and far beyond the resources of these companies. Nobody knows how to produce the tritium needed to operate, or to extract it at ppb concentration if they did. Nobody knows how to build structural elements that will not fall apart after a few months' neutron blast. It has been decades since either was seriously looked at, with no promising ideas forthcoming. That hasn't mattered much thus far because Q is so far off, and investors pour money in regardless.
- NKosmatos 4y agoJust 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 we get there sooner than later.
- cl0ckt0wer 4y ago"our need will be the real creator" - Plato
- SapporoChris 4y ago"Necessity is the mother of invention" Proverb of unknown origins. Earliest reference Aesop's fable. I've been quoting the proverb for a long time. Thank you for the quote, I feel it says basically the same thing but I appreciate the different wording and that it is attributed to Plato.
- ChrisMarshallNY 4y ago"Laziness is the mother of invention." - Forgot where I heard that. It may have been a comedian.
- moogly 4y ago> 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.
- simonebrunozzi 4y agoI 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.
- hammock 4y agoWhat are all the valves and ports and things in the metal outside of the stellarator in the lead illustration?
- willis936 4y agoHeating and diagnostics. https://www.researchgate.net/figure/Port-allocation-of-the-W7-X-heating-systems-showing-the-positions-and-injection-geometry_fig10_271978056 https://www.researchgate.net/figure/Port-allocation-of-the-W... There's a chapter on W7-X diagnostics in this DOI (check sci-hub). It doesn't include a comprehensive list of diagnostics or their port assignments, but it was the best I found at a glance. 10.1007/978-1-4613-0369-5_76
- ncmncm 4y agoYou need to start these things with a hard vacuum inside before you inject your fusile material.
- deleted 4y ago[deleted]
- davesque 4y agoWhat's the theoretical advantage of the German stellarator over a tokemak? Seems like a complex design but I assume there must be a reason for the complexity.
- speeder 4y agoI am complete layman here. Still from what I read the whole point of stellarator is to be same as tokamak except you use CAD to make it twist in the same way plasma naturally would twist, to make it easier to keep the plasma in the path you want.
- sac_ 4y agoThe main advantage is that a Stellerator can be continuously operated while a Tokamak only works in pulsed operation. The complex design of a Stellerator's magnectic coils essentially avoid the need for a transformer as it is being used in a Tokamak. The transformer is the reason why a Tokamak can only be operated in pulsed mode. However, there is ongoing research to achieve continuous operations e.g. by means of high-frequency waves. Much better explanation here: https://www.ipp.mpg.de/14869/tokamak https://www.ipp.mpg.de/14869/tokamak
- TaylorAlexander 4y agoHas anyone published research on concepts for a stellarator that uses high field magnets like the SPARC/ARC systems? Obviously the idea is that it would be smaller, but I am curious if there are any interesting specifics for such a machine. You could imagine that if W7-X and SPARC show good results in the next 5 years then a high field stellarator design would start to look pretty interesting.
- willis936 4y agoBoth Type One and Renaissance (mentioned in the article) are HTS stellarator startups. I'm not sure if they've published power plant studies, but they've certainly pitched them.
- TaylorAlexander 4y agoAh great thank you! I only scanned the article. I will see if they have published anything.
- stjohnswarts 4y agoSo for those of us who just want fusion without the physics explanations; is there any possibility a stellerator could actually give us a net Q (including -all- the power put into the process, and not just point of fusion) ? or is it just a good place to run fusion experiments?
- ncmncm 4y agoGetting to net Q leaves you very, very far from useful fusion. Structural material that can stand up to the neutron bombardment has not been identified; no one has worked on it in decades. No one knows how to breed enough tritium to fuel it, or how to extract it from the shielding ("blanket") fast enough to be useful, if indeed they did manage to breed some. Current estimate is that working fusion is 40 years off and receding. People, and particularly startup companies, insisting otherwise are simply lying through their teeth. Securities fraud is poorly enforced. Q is thus not very important, except maybe for getting more money. So, there is nothing here to get excited about unless you are very keen on plasma fluid dynamics. Plasma fluid dynamics is probably the hardest kind of physics, so anybody who can do it deserves respect. It is a shame we can't find much for them to do besides fool with fusion and work on actually-useful ion propulsion.
- spaetzleesser 4y agoWendelstein 7-X is a fusion experiment. It's far away from a functioning reactor but gives a lot of input into possible designs.