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The first room-temperature ambient-pressure superconductor?

arxiv.org

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Re: The first room-temperature ambient-pressure superconductor?

#771

Post by Filligree »

jacquesm wrote: post #758
Filligree wrote: post #739

Earlier quoted context omitted.

The figures I’ve seen for superconducting energy storage are in the regime of “10GWh per km of cable”. Quite a bit more than chemical, in other words, the chief problem being what happens if it quenches. Or the cables break. And cost.

Room temperature super conductors don't quench. Or at least, not until they reach the temperature at which they no longer work as superconductors, which for this one is 127 degrees Celsius . That does make for an interesting failure mode if anything should every cause a small spot on a longer conductor to reach that temperature...

"Beam of light shooting the heavens" value of "interesting", yes. Though I suppose it would look like a small tactical nuke in effect.

Re: The first room-temperature ambient-pressure superconductor?

#772

Post by treeman79 »

nvm0n1 wrote: post #761
klodolph wrote: post #689

Earlier quoted context omitted.

The direct impact could be relatively limited, at least for a while. Having a room-temperature superconductor is really awesome, but existing high-temperature superconductors are fragile and expensive. You can make motors, electromagnets, and power grids with much better efficiency—but that’s not so useful if the parts break when you look at them wrong. You’ll still get better magnets and sensors, probably. Maybe eve…

Isn't the big win of superconductors that you can build batteries with them? Like, you just pump them full of power that goes round and round forever with no or trivial losses. I always heard that this was why they were interesting.

Until someone sneezes and all the power is released at once.

Re: The first room-temperature ambient-pressure superconductor?

#773

Post by mabbo »

jacquesm wrote: post #456
andreiklochko wrote: post #389

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

This is a dancing pig. The thing to appreciate is not how well it dances but that it dances at all .

This is one of those lines that sounds like it came from a book of quotations, but I can't seem to find any source beyond this post.

Re: The first room-temperature ambient-pressure superconductor?

#774

Post by inglor_cz »

zamalek wrote: post #694
justahuman74 wrote: post #680

Earlier quoted context omitted.

As someone who doesn't follow superconductors, what sorts of things about life/engineering/society would change, how dramatic would it be, and more importantly: which stocks would you pick :)

The changes would be more dramatic than the discovery of fire, but would occur gradually.

The changes introduced by discovery of fire were very gradual. No Internet, no written language at all: any innovation back then could only spread as quickly as humans walked, and would temporarily stop at every significant geographic barrier such as sea.

Compared to the discovery of fire, the changes from room temperature superconductors would be a flash fire.

Re: The first room-temperature ambient-pressure superconductor?

#776

Post by tsimionescu »

yyyk wrote: post #749
tsimionescu wrote: post #703

Earlier quoted context omitted.

I believe the biggest envisioned possibility is superconducting power lines. Those would allow long-distance power transfer with minimal losses. In the most idealistic scenario, you could imagine a belt of solar power plants around the globe connected by superconducting power lines, providing solar power 24h a day. Of course, there are huge hurdles to such a project even if we did have the superconducting lines, but…

>In the most idealistic scenario, you could imagine a belt of solar power plants around the globe connected by superconducting power lines There's no technical impairment for doing this with current tech, and it's not clear the new tech is cheaper. Power lines are already very efficient, especially the long-distance ones. We would save a bit on converting from HVDC to AC but that's also very efficient.

The numbers I found on a quick search are 3% loss per 1000 km for HVDC lines. That's a pretty huge loss for the 20k+ km lines you'd need to transmit power from daytime to nighttime areas on the globe.

Re: The first room-temperature ambient-pressure superconductor?

#777

Post by throwawaymobule »

sheepscreek wrote: post #505
xxpor wrote: post #322

Earlier quoted context omitted.

One catch would be the use of lead would restrict the use cases fairly heavily

This is a phenomenal find in any case. As for how to avoid lead poisoning, coat the lead with a thin layer of some substance, perhaps a plastic or rubber that doesn’t affect its magnetic capabilities. Or perhaps they can galvanize it with safer metal, leaving a really small part exposed.

I think people are talking about RoHS rather than practical danger. Since RoHS is incredibly strict about quantities, e.g. if you can mechanically seperate a piece of the widget, that's what gets measured.

It'd likely be exempt though.

Re: The first room-temperature ambient-pressure superconductor?

#778

Post by rbanffy »

jacquesm wrote: post #757
rbanffy wrote: post #732

Earlier quoted context omitted.

One thing I can imagine is desktop MRI machines, or, at least, much cheaper and less finicky big MRI machines that don’t take days to chill to operating temperature. Maglevs are also a popular guess - safer, faster, and more power efficient ground mass transport would be a huge thing. Maybe even magnetic rail space launches. And, of course, military applications (the last few examples I mentioned involve acceleration…

Make sure you don't have anything metal lying around your desk.

Maybe if it pulsed the magnetic field very quickly it wouldn't be a big deal.

Re: The first room-temperature ambient-pressure superconductor?

#779

Post by yyyk »

tsimionescu wrote: post #776
yyyk wrote: post #749

Earlier quoted context omitted.

>In the most idealistic scenario, you could imagine a belt of solar power plants around the globe connected by superconducting power lines There's no technical impairment for doing this with current tech, and it's not clear the new tech is cheaper. Power lines are already very efficient, especially the long-distance ones. We would save a bit on converting from HVDC to AC but that's also very efficient.

The numbers I found on a quick search are 3% loss per 1000 km for HVDC lines. That's a pretty huge loss for the 20k+ km lines you'd need to transmit power from daytime to nighttime areas on the globe.

I thought these were mostly fixed conversion losses, but checking this again you're right, it's 3% per 1000km (not including the conversion loss at the stations).

Re: The first room-temperature ambient-pressure superconductor?

#780

Post by hollerith »

hguant wrote: post #719
hollerith wrote: post #617

Earlier quoted context omitted.

I worded my original assertion the way I did (lead replaced with copper) so that it would be true even if the majority of the bullet is steel. >I get that you're trying to be snide because you were so publicly wrong, but your tone here really just makes you sound like you're trying to sound smart Right back at you. I don't think I'm motivated by trying to sound smart, but rather by curiosity about the subject. Well,…

Answering without doxxing myself is harder than I thought. The last time I was on a US military range, which to be fair was right before the pandemic so things probably have changed - we drew green tip (M855) from the range master. My understanding was that a) the steel targets were getting beat up by A1 and there wasn't any money to replace them and b) we weren't a combat group so we didn't rate the good shit. EDIT…

Thanks for taking the time to set me straight on that. I didn't realizes I was posting misinformation when I wrote, "the US Army has completely stopped using lead in bullets".
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