LK-99 would have interesting applications, known and unknown, but we have a pretty good understanding of superconductors based on 100 years of practical research, and I find this kind of instant punditry pretty tiresome.
LK-99 would have interesting applications, known and unknown, but we have a pretty good understanding of superconductors based on 100 years of practical research, and I find this kind of instant punditry pretty tiresome.
REBCO supports stronger magnetic fields, and conveniently, tokamak output scales with the fourth power of magnetic field strength.
So instead of being 400 times the volume of a PWR with the same gross power output, they're just 40 times the volume. It's no panacea to the economic challenges facing fusion.
The other way to get high volumetric power density is go with a configuration of higher beta, the ratio of plasma pressure to magnetic pressure (fusion power at a given magnetic field scales as beta^2). Helion isn't using superconductors at all.
You're correct, and this highlights a problem I often see in discussions: "efficiency" just is a measure of benefit/cost. Without knowing the units of benefit and cost, people aren't making meaningful statements when they say "efficient". The important efficiency of transmission lines is capacity per dollar, not capacity per material, and no material requiring lab crystallization is going to be remotely competitive in capacity per dollar.
Maybe new technology made in a lab can one day scale up and compete against current low-cost high-scale solutions. Crazy idea, I know.
However, trying to artificially limit all discussion about R&D and future tech by claiming "it's more expensive than fully scaled solutions" has got to be full luddism. This loom prototype is too expensive! I can hire a man for a shilling a day!
>material requiring lab crystallization
How are you going to string a crystals between towers? The material properties are all wrong for this application.
As far as I'm aware this is a brittle /inflexible material so my point about the mechanical properties still stands.
And when people refer to growing crystals, that generally refers to a particular kind of crystal. Ive never heard of anyone growing aluminium crystals, except if it's a compound, and then you get a crystal like we think of when we say crystals.
Yes. You want them to be ductile (malleable, or that can be deformed permanently in less-technical language). Although they could also be flexible (meaning that they can deform, but go back to their natural shape if we stop applying a force), as in the case of fibre optics cables, which are actually not crystals but quite brittle.
The interesting twist is that a solid pretty much has to be a crystal to be malleable. Almost all the metals you can think of are in their crystalline state.
> And when people refer to growing crystals, that generally refers to a particular kind of crystal.
I don’t know. From my experience people equate crystals with shiny things without really thinking about it. But this is HN, and we should try to be a bit better than a random person on the street. After all, most people don’t know a web browser from an OS, but I would be ridiculed if I make that confusion here.
It is a wonderful community where you are almost certain to discuss with some experts in pretty much any given field, it is a great opportunity to learn and grow.
> Ive never heard of anyone growing aluminium crystals
If you’ve seen solid aluminium, then you’ve seen it as a crystal. It is pretty much impossible with common techniques to get non-crystalline solid aluminium.
> except if it's a compound, and then you get a crystal like we think of when we say crystals.
That’s the thing, I don’t know what you think of when you say “crystal”. In actual fact, a crystal is a state of condensed matter in which atoms or ions are aligned in a 3-dimensional pattern that can be replicated to fill the space. In the case of aluminium, you can actually see how the atoms are arranged in a periodic way in articles such as this one (figure 3): https://www.researchgate.net/publication/323423565_Anomalous... . There are many other examples, and it is absolutely fascinating. We have the tools to count atoms and see the structure of the material!
And it is undoubtedly a crystal.
A ceramic?
I'm happy to accept that internet explorer isn't an OS, but it would be nice to know what terminology you would find acceptable.
I am not blaming you, I know the knowledge of the general population of this sort of things is not great and you cannot know it before some tells you. A whole bunch of new age scams would completely fall apart if most people actually knew what a crystal is and where we can find them.
They are not ceramics because this is used for compounds with elements such as oxygen or nitrogen, which is not applicable here. Aluminium oxide, Al2O3, which used in sapphire "glass" in watches, is a ceramic that contains aluminium.
No, you're just the one pedantically enforcing a definition that's irrelevant to the conversation at large.
You aren't holding up your end of the conversation. Being a good listener means putting some effort into understanding what people are trying to say even if they get terminology a bit wrong. Jumping in to correct people on minor misuses of terminology doesn't show you're smart, it shows that you care more about correcting them than about their ideas.
I mean, cool, good to know copper and aluminum are crystalline metals, but the point here is that they're ductile and LK-99 isn't--you can't make wires out of LK-99. Arguing that copper and aluminum are crystals isn't adding to the conversation, it's just missing the point.
> No, you're just the one pedantically enforcing a definition that's irrelevant to the conversation at large.
I am not enforcing anything. How could I, anyway? I am pointing out an error in terminology. It is far from irrelevant, all the threads about that subject are full of misinterpretations and misunderstandings. One of the reason for that is that scientific articles use the jargon of the field, which can deviate from how certain words are used in our daily lives.
> You aren't holding up your end of the conversation. Being a good listener means putting some effort into understanding what people are trying to say even if they get terminology a bit wrong. Jumping in to correct people on minor misuses of terminology doesn't show you're smart, it shows that you care more about correcting them than about their ideas.
It is not a small vocabulary issue. This stuff is fundamental materials science and you cannot understand anything about this subject if you are confused about this. Again, this thread is full of people who are confused because they don’t understand some words in the same way as the writer. Crystalline and amorphous materials have very different properties as far as conductivity is concerned. The crystalline aspect is fundamental.
> I mean, cool, good to know copper and aluminum are crystalline metals, but the point here is that they're ductile and LK-99 isn't--you can't make wires out of LK-99. Arguing that copper and aluminum are crystals isn't adding to the conversation, it's just missing the point.
What is missing the point is that we know how to make wires with brittle materials. Prime examples are silica in fibre optics and YBCO in superconducting tape. And yes, whether they are crystalline or not is very important for both of them.
No, even at scale, materials that you can extract from ore are inherently going to be cheaper than materials you have to extract from three different ores and then crystallize, even in a manufacturing lab. These just aren't comparable processes, and no amount of scale is ever going to fix that.
Instead of assuming I'm making a disingenuous point, you might have asked for clarification.
That's setting aside the problems others have brought up, which is that the materials in question have other properties besides conductivity which make these materials inappropriate for transmission application.
As with all toy models being applied to the real world, there are important factors to model in that aren't immediately obvious.
I suppose I didn't expect that we necessarily had like, the "absolute most efficient that could be made" (if that is something substantially more complicated at a materials-science level than "some simple-to-make-alloy"), but I hadn't imagined that it was a substantial difference. (I think I had imagined that they were... copper wires with like, surrounding metal tubes, or something? I hadn't thought much about it.)
Could you either say, or give my a search term I should look up in order to read, a little more about the trade-off being made between materials cost and efficiency of transmission lines?
Super conductors are superconductive to a point. Once that point is crossed they turn into regular conductors. (I've seen ~1A cited. For context, EVs charge at around 500A).
To make them useful for power transmission, you'd have to up the voltage to insane levels to avoid collapsing the field.
The AmpaCity project in Essen, Germany, gives insights about the implementation details, as the involved parties were required to publish their work.
https://www.enargus.de/pub/bscw.cgi/?op=enargus.eps2&q=%2201...
for the specific aspect under discussion, the Karlsruhe Institute of Technology report is of interest:
https://www.tib.eu/de/suchen/id/TIBKAT:872231372/Ampacity-10...
[0] https://en.wikipedia.org/wiki/Yttrium_barium_copper_oxide#/m...
[1] https://www.amsc.com/comed-and-amsc-announce-successful-inte...
If we did discover a room-temperature superconductor, I suspect it would be a while before the cost to produce it in the bulk quantities required for electrical transmission are economically attractive compared to what’s already available.
Communication/low voltage is a different matter of course.
They might find a niche in some instruments in probes, but for wiring it does not make sense. The rest of the probe electronics don't like being that cold.
Note that there is no guarantee that that would ever happen. Electrical resistance is not the only thing you need for something to be an economically efficient power line. While superconductors are by definition excellent in terms of electrical resistance, there is nothing to guarantee that they wouldn't be too brittle, or too heavy, or too hard to mould into the required shape, or simply require materials that are too rare on Earth. And all of these would not be things that can just be worked around with better production processes or smart engineering - they would be fundamental limitations of the specific material, just like the low temperature requirements of currently known superconductors will never be improved with more research.
So this isn't a matter of when they would reach the point of being better economically, it's also very much a matter of if they would ever reach that point. Hopefully, we'll get lucky one day and find a material that is superconducting at room temperature and above, that is study and light and easy to make into wires and made out of abundantly available elements. LK-99 certainly wasn't most of these things. Even if it had been superconducting, it wasn't a good candidate for any of the other properties we want anyway, so it likely wouldn't have been much better than other known materials for most applications.
There is a good chance that they never reach the exponential breakpoints that everyone likes to fantasize about.
In other cases it is more important to reduce resistance, not so much because of the power loss but because of what the power loss means: the generation of heat that may be difficult to remove.
Of course you can get around those problems at extra cost, but it is more than a straight up comparison of the material cost of the conductor.
Very expensive to build anything sizable out of it
It does have excellent anti-corrosion properties.
I wonder what kinds of alloys we will see in the potential future with asteroid mining and thus comparatively cheap gold. Imagine replacing lead with gold in industrial applications. Or the stainless steels with a gold component in them.
My guess is the main application will be for space missions that find it cheaper to carry mining/manufacturing equipment rather than all the materials they need. Even that seems potentially a ways off. I suppose we could mine asteroids for science sooner, but that's quite a bit different than any mission plan which includes mining as a part of the required logistics. Maybe if there's some materials needed for extending life support capabilities? But still I'd have to wonder why not just take the extra supplies with you.
Maybe a moon or Mars base could change some calculus. As I suspect the break even point of such a plan may require lots of use of any such equipment.
Aluminum wires even made it into residential housing when copper was expensive/rare. https://en.wikipedia.org/wiki/Aluminum_building_wiring
Copper is expensive so over hundreds of miles you may not want that.
So popular science wraps it in a "what you could do with it. maybe. possibly." Or what it means. And commenters have latched onto it, but a lot is said with an air of confidence, of just-so. "Oh uh, superconductors, conducting is passing electricity from one end to the next, super is like really good, uuh uh uh... I know, what about power lines from the Sahara to Europe so they can build solar collectors down there!"
Same with exoplanets, the actual science is "yeah the luminosity of this star drops by 0.0003% at a cycle of 300 days and we're getting some photons that indicate there may be hydrogen molecules", pop sci turns that into "EARTH-2 TEEMING WITH LIFE DISCOVERED, GENERATION SHIP WHEN?"
Which seems ideal to me. Very educational.
I hope that those that got dashed (and observed the dashing) take a step back the next time something from "FuturistSuperScienceNews.com" or whatever pops up touting a revolutionary XYZ. Those sites are like 99% trash that train their readers to distrust science when their clickbate articles don't pan out. If I were conspiracy minded, I'd swear they exist to build out a mistrust in institutions.
They achieved this fusion by creating a container of material that produced massive amounts of xrays when it was bombarded by a high powered laser. These xrays caused another container's surface to ablate at such a rate it compressed its interior to the point that fusion was achieved.
However, this being a weapons lab, they created the experiment to model the secondary device in an H-Bomb. The secondary is theorized outside the Top Secret world to be a cylindrical tamper of (enriched?) uranium. One hypothesis in the public sphere, is its the primary device's Xrays that cause this to ablate at such a rate and that the inside is compressed to achieve fusion. The purpose of the fusion is primarily for the neutrons it generates, which are used to cause a massive amount of fission in the tamper, producing the majority of the energy. For example, if replace the uranium with another non-fissile material, and you have a "neutron bomb".
The reason the breathless hype annoyed me is that at no point was usable energy the desire of the test. In fact, the test solely was to feed real world data back into the supercomputer models, so that we know how our existing stockpile of weapons would work or even perhaps to find optimizations. We know this mechanism of ablation causing fusion works, we've known for 60+ years, all we're doing is doing it in a lab.
I'm not sure why there is this need to hype these events, like fusion or LK-99 so much. It seems that being a naysayer is reacted to as if the naysayers are explaining a magician's tricks. As if we don't hype these events the public will lose interest, or even our children will drop out of STEM careers.
You are telling me that a US weapons lab just announced a successful path to a laser triggered pure fusion bomb? Yikes!
Not actually sure if it can be used to ignite more fusion fuel, but if they using this to test secondaries then it sounds like it might.
I really hope we get fusion reactors before pure fusion bombs, as pure fusion bombs are going to be a nuclear non-proliferation nightmare. While it might not be easier to built pure fusion bombs than bombs with a fission trigger, controlling the precursors and knowledge is going to be very difficult.
> "Fusion power is here! All we need to do is engineering!".
I agree with this statement and it has been true of fusion since at least the early 2000s. Don't underestimate the difficulty of engineering. Safe fission breeder reactors are an engineering problem as well, one which humanity has largely abandoned due to repeated failures.
However... In the early 80s, the SDI initiative aimed to have orbiting satellites that utilized x-ray lasers to shoot down incoming warheads. The theory of these were you had h-bombs in orbit, with long cylinders of a material that would amplify the x-rays from the bomb. You'd point these at the incoming warheads and trigger the bomb and (chefs kiss) you have beams of xrays that would destroy warheads.
One of the major reasons this was skuttled, was that the test they used to find a material they thought amplified xrays was flawed (see below).
With the test-ban treaty, they weren't able to test any other materials. Now we have a facility that tests materials to amplify x-rays...
Sidenote: The test was, explode a bomb in a tunnel, shut the tunnel down with explosives to trap the shockwave, then use the xrays to test materials to withstand x-rays as well as amplify them. Teller thought they had seen amplification and sold the military on the satellite idea. Another scientist, thought it was a secondary thermal effect on Oxygen. There is an interesting story about the back and forth, and the pressure to have another scientist lose his credentials for disagreeing with Teller, that is a good follow on to the Oppenheimer story. https://en.wikipedia.org/wiki/Project_Excalibur
I agree with you, if you have fission triggers, you aren't going to want to use lasers. At least with today's lasers.
> I wouldn't be too worried about this test creating a new weapon.
My concern is that NNP has focused on controlling access to fissionable material, so potentially this is a path to h-bomb that doesn't require fissionable material. As lasers get better, secondaries that don't use controlled fission materials become a risk. At what point does the world start having to worry about controlling access to lasers? How does this impact the future research and funding of lasers?
Additionally if you can test h-bombs without tests. This also makes it easier to develop and test a h-bomb without revealing you have an h-bomb. Typically nuclear weapons tests are detectable via seismographs.
If you remove that, those things become... really, just tubes wrapped in various coils connected to a software defined radio of average quality.
Also you can't just write off the fringe field.
Would a cheap room temperature superconductor bring any benefits here?
High-efficiency DC-DC converters often use a resonant tank circuit[1], which supports high-frequency operation and zero-current or zero-volt switching, which together significantly reduces switching losses.
In such a circuit I imagine superconducting inductors/transformers and superconducting capacitors could be beneficial to improving efficiency further.
Keep in mind though that resonant DC-DC converters can reach 98% (or higher) efficiency already[3] with current tech.
[1]: https://www.analog.com/en/technical-articles/an-efficiency-p...
[2]: https://www.monolithicpower.com/understanding-llc-operation-...
[3]: https://ietresearch.onlinelibrary.wiley.com/doi/10.1049/iet-... (random example)
Can you point me in the direction to learn more about this?