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hunson_abadeer | 2 years ago

This is precisely what put me off in these discussions. Not the idea that we might have found a room-temperature superconductor - that part was exciting. It's the part where people confidently talked about its applications without realizing that they probably wouldn't revolutionize CPU performance (Josephson junctions don't seem to work well as non-cryogenic temperatures for reasons unrelated to superconductivity), power grid transmission (transmission lines are already pretty efficient and we already choose less efficient materials for cost), or energy storage (LK-99 would likely have a fairly modest current limit before it stops superconducting).

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.

discuss

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raphlinus|2 years ago

Amen. When someone does the math and adds up the winners and losers in all this, one clear winner will be this video from Asianometry, entitled The History of Superconductors (Before LK-99)[1]. It only lightly touched on LK-99 itself, but did an excellent job going through the actual science-based history of superconductors, covering in particular detail previous hype waves. A major point is that the YBCO superconductors, while an amazing scientific discovery, haven't had revolutionary applications, and have only lightly displaced lower temperature (niobium-titanium metal alloy) superconductors in applications requiring generating strong magnetic fields, including MRI machines. For the curious, [2] goes into considerable detail on potential applications and challenges for HTSC in MRI.

[1]: https://www.youtube.com/watch?v=wUczYHyOhLM

[2]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5472374/

DennisP|2 years ago

REBCO is revolutionizing fusion reactors. Several companies are using it to build tokamaks with the same performance as ITER, but in a tenth the size.

REBCO supports stronger magnetic fields, and conveniently, tokamak output scales with the fourth power of magnetic field strength.

kerkeslager|2 years ago

> transmission lines are already pretty efficient and we already choose less efficient materials for cost

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.

criley2|2 years ago

This is an absolutely disingenuous point that compares the cost of full-economy-of-scale tech to literal one off R&D prototypes.

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!

rubylark|2 years ago

In this context, they are speaking of electrical efficiency, i.e. the amount of power lost to system impedance during transmission, not some abstract concept like effectivity. The efficiency of a transmission line is expressed as a ratio of power received at one end of the line over the power sent at the other.[1]

[1] https://en.m.wikipedia.org/wiki/Electrical_efficiency

drdeca|2 years ago

I had heard the parts about "probably wouldn't be a big deal for CPU performance" and "probably wouldn't be great for energy storage", but I hadn't heard the point about "we use less efficient materials for power grid transmission than we could, because of costs".

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?

svetb|2 years ago

Am not the author of that comment, but the fact that comes to mind is that aluminum is used for virtually all transmission and distribution lines - for price reasons - even though copper has better conductivity.

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.

MobiusHorizons|2 years ago

We frequently use aluminum wires with a higher thickness to make up for the lower conductivity as compared to copper. It’s not as simple as cost vs performance though, as aluminum is substantially less dense than copper. Gold and silver are also better conductors than copper, but of course are very expensive, and still have resistance. Zero resistance may be with it on some cases. For instance in projects that currently use high voltage dc it may be worth it due to safety and complexity wins, but that all would depend on how hard (expense and complexity) the superconductor is to deploy.

cogman10|2 years ago

The crux of the problem for superconductors used as power delivery is the "critical field" problem. [1]

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.

[1] https://en.wikipedia.org/wiki/Critical_field

TylerE|2 years ago

A 2" diameter copper wire will have lower losses than a 1" diameter copper wire.

Copper is expensive so over hundreds of miles you may not want that.

trzy|2 years ago

Accelerationism has become a religion for many people working in tech. Social media is teaming with John the Baptists heralding the next messiah.

Cthulhu_|2 years ago

This is the curse of popular science websites hyping things up; most people, present company included, have no idea what the scientific language means - be it superconductivity, LHC results, or astronomic spectrography.

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?"

burnished|2 years ago

Interesting, from what I saw a lot of people got informed on why those overly confident predictions were drek - I don't know that I have seen a claim go unchallenged.

Which seems ideal to me. Very educational.

cogman10|2 years ago

It was like stomping out weeds and it wasn't always well received.

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.

jboy55|2 years ago

I felt a similar way with the news of the fusion 'breakthrough' around 6 months ago. "Fusion power is here! All we need to do is engineering!".

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.

EthanHeilman|2 years ago

> 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.

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.

Forgotthepass8|2 years ago

It also wouldn't change much in MRI (formally NMR) -- it's also very limited on other factors

pbmonster|2 years ago

I mean, both NMR spectrometers and medical MRI machines would be a hell of a lot less complex without the cryostat.

If you remove that, those things become... really, just tubes wrapped in various coils connected to a software defined radio of average quality.

KSteffensen|2 years ago

A large part of the energy loss in electronics happens in switch-mode Buck-Boost DC-DC converters, as I understand it mainly due to internal resistance in the components used and due to the magnetic field not being directed enough to transfer 100% power between two inductors.

Would a cheap room temperature superconductor bring any benefits here?

magicalhippo|2 years ago

For "normal" DC-DC converters it's the losses in the semiconductor switches and diodes that dominate[1], unless cheap inductors or capacitors are used.

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)

floxy|2 years ago

>Josephson junctions don't seem to work well as non-cryogenic temperatures for reasons unrelated to superconductivity

Can you point me in the direction to learn more about this?

Fatnino|2 years ago

I think it would make MRI machines cheaper

laserbeam|2 years ago

Also... The material was always a ceramic, and you can't do much with other ceramic superconductors either.