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Room temperature superconductivity itself is not revolutionary for anything except academic papers. Lossless power lines and frictionless trains are a gimmick a
by effie 6y ago
Room temperature superconductivity itself is not revolutionary for anything except academic papers. Lossless power lines and frictionless trains are a gimmick as those losses are small part of their operating cost. Resistance of copper cables is very small and acceptable already. When price of superconducing cables is comparable to copper cables, then it becomes interesting.
- erikpukinskis 6y agoIsn’t superconducting a requirement for fusion reactors (for plasma confinement)? I think all the cooling required for that is a major impediment to both the design and the efficiency.
- effie 6y agoI think you are right for tokamaks, room temp superconductor would change the design somewhat.
- MayeulC 6y agoIn existing superconductors, you break superconductivity if your magnetic field reaches a certain threshold. That limit decreases, the closer you are to the temperature limit. So yeah, higher-temperature superconductors could either give you higher-temperature supermagnets, or same-temperature stronger magnets. The latter is being explored with relatively new materials, for smaller tokamaks, which enabled by stronger magnetic fields.
- anonuser123456 6y agoYou don't need room temp superconductors to make those magnets. REBCO tape can be cooled by liquid nitrogen. It's what they are using for the various tiny Tocamak projects.
- travisoneill1 6y agoWhy is this material not used for MRI's?
- woeirua 6y agoThis material only appeared in the last 10 years as a practical way of creating strong magnetic fields. Give it enough time and you'll see most MRIs transition away from the large hulking behemoth machines that we have today into much smaller and more portable machines. Also, as an added benefit you can use liquid nitrogen to cool them instead of helium.
- anonuser123456 6y agoAs sibling post noted, likely time. Existing designs have 4 decades of inertia behind them. South Korean and Japanese researchers definitely have it on their radar. https://ieeexplore.ieee.org/document/9000570 https://ieeexplore.ieee.org/document/9000570
- punnerud 6y agoAnd MRI-machines. Are you able to make superconducting self sustaining outside the laboratory it can have a lot of great implications: Reduce the cost of MRI (huge helium cost), make extremely fast batteries for regeneration of power, very efficient and small motors +++
- effie 6y agoMRI machines don't necessarily need helium even today. It just the common model family using Niobium-Tin wires you see in hospitals or media. There are permanent magnet MRI machines. What do you mean by "fast batteries"? For regenerative breaking one can already use supercapacitors. Will room temp SMES cheaper than that? Electric motors are pretty efficient and small already, there is 0.6mm motor from Namiki. Sure they can get smaller. How does room temp superconductor help that? Smaller motors have better cooling than big motors so ohmic heating is not a problem.
- anoncareer0212 6y agoTo be fair, the article takes some care to point out that cables are likely impossible
- effie 6y ago... with this method. My point is, even if we have room temp room pressure superconductors, this isn't as revolutionary by itself. The price is key and ordinary copper is likely to win in most places except where price does not matter, or where we need the very strongest magnets.
- pixelbash 6y agoI'm imagining if superconductors become widely used it will be in small quantities and for their unique properties that cannot be achieved otherwise. Not for minor benefits over alternatives?
- ReptileMan 6y agoBut what about energy storage? How much current you can pump in a closed circuit?
- contravariant 6y agoThe current has some limits, but with enough copper you can probably put some serious amperage on it, and a superconductive magnet in "persistent mode" can apparently keep going for months. Not sure how I'd feel about several MWh in a single circuit though. It might be easier to just build a big flywheel.
- Hextinium 6y agoIssue with flywheels tends to be containment when they explode, flashing a MWh of metal due to containment failure I would hope to be safer. Additionally a superconductor wouldnt have gyroscopic forces to worry about.
- gus_massa 6y ago1MWh is almost 1 ton of TNT. If you have that energy in a flywheel or in a electric circuit and something goes wrong, you need containment in both cases. If the circuit losses superconductivity and a part overheats, it will release 1MWh in a very short time, that will cause an explosion.
- adrian_b 6y agoIn a superconducting coil there are similar repulsive magnetic forces, which can easily disintegrate the superconducting wire at very high currents. Therefore the coil assembly must be designed to support the wire and resist to the highest forces expected. So there are similar problems with flywheels and superconducting coils, in the case when the stored energy densities are also similar.
- contravariant 6y agoYou should look up what happened at Cern when they had a superconductor meltdown. And that one wasn't even a burst of power it was a continuous current (admittedly one with enough to power a small city). Of course anything with that much energy is possibly violent, but at least a flywheel is easy to control. I haven't the faintest idea what that amount of electromagnetic energy would do, I'm not sure I want to find out. At the very least I suspect you'll find that electromagnetic current also has angular momentum at those scales.
- dplavery92 6y agoSuperconductivity is phenomenologically different than "very low resistance." The excitement about high-temperature superconductors is not only that there will be less power dissipated through power lines, but they will enable new technologies in power generation, high-energy physics research, analog and digital circuitry, sensors, and communications.
- MaxBarraclough 6y agoAs someone who knows nothing about this: what would the most obviously useful applications be, if we discovered practical room-temperature superconductors?
- asdfadsfgfdda 6y agoEnergy storage would be pretty useful, the efficiency could be even better than batteries: https://en.wikipedia.org/wiki/Superconducting_magnetic_energy_storage https://en.wikipedia.org/wiki/Superconducting_magnetic_energ...
- effie 6y agoThe only discipline in which SMES are an interesting option is high-power pulse sources. For storage of power plant production they are not interesting, as their energy density is order of magnitude lower than those of batteries. They are too heavy and too big. This problem does not go away just by having room temp superconductor. It would have to have incredibly high critical magnetic field strength and be very cheap. > https://snf.ieeecsc.org/sites/ieeecsc.org/files/CR5_Final3_012008.pdf https://snf.ieeecsc.org/sites/ieeecsc.org/files/CR5_Final3_0...
- asdfadsfgfdda 6y agoI think it could scale. If you can directly transfer mechanical stress from the cable to the earth, with no concerns over vacuum or thermal insulation, the economics might work. Even if you can only store ~1 Wh per kg of enclosed rock, it seems possible to enclose millions of kgs of granite in a solenoid.
- deelowe 6y agoI don't think the elimination of cable losses is near the top of the list when it comes to discussions around why high temperature SC is revolutionary.
- effie 6y agoAnd what is top of the list, then?
- MayeulC 6y agoStronger magnets! Better magnetic bearings! RF circuits. If superconductors were feasible on integrated circuits, I'd expect the TDP to get lower, enabling higher frequencies and integration (3D?). Frequencies would still be limited by propagation delay, but we have some room to grow. Classic FET wouldn't work, I think, at least not without bringing back switching losses, but there's probably a way to create a magnetic transistor using a few superconductor wires (locally increasing resistance above 0, for instance). Or use FETs with adiabatic computing, who knows? Future seems bright, and applications for room-temperature superconductors are aplenty. It's just that everyone thought of them as a pipe dream, so they aren't really being investigated that I know of. I wish that link had a better list: https://en.wikipedia.org/wiki/Technological_applications_of_superconductivity#High-temperature_superconductivity_(HTS) https://en.wikipedia.org/wiki/Technological_applications_of_... At least with a PoC, we might see a revival of real interest in them. Not sure how long it will last, though.
- effie 6y agoSuperconducting computer will still dissipate heat, as there is minimum cost per element switch due to thermal noise. This makes superconducting computers more efficient at lower temperatures. Room temp superconductor would be cool for making research simpler though.
- deelowe 6y agoI imagine energy storage would be up there.
- tasty_freeze 6y agoHaving another data point will help in shaping their understanding of the phenomenon, which may lead to future more practical developments. So don't discount the fact this is an academic result. Power line losses are not insignificant, and put a limit on how far power can be shipped. Solar and wind variability is a problem, but if power could be shipped anywhere on the grid with no transmission line losses (there would still be other losses) it would do a lot to smooth out local variations in power generation.
- effie 6y agohttps://www.eia.gov/tools/faqs/faq.php?id=105&t=3 https://www.eia.gov/tools/faqs/faq.php?id=105&t=3
- tasty_freeze 6y ago5% is not insignificant, and it is that low because electricity is routed to nearby consumers as much as possible.