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What exactly are the interesting use cases & practical applications of room temperature superconductors?



just from the top of my head:

- transport electricity from anywhere without losses - handheld tomography devices - super powerful small/light electric motors - light electric motors means: electric planes - cheap maglev trains - rail guns - possibly faster computer chips using josephson junctions


> super powerful small/light electric motors - light electric motors means: electric planes

I would be extremely sceptical that this would help electric planes all that much. Current brushless motors aren't really all that heavy for their kW output and already boast 90% efficiency at optimal load and RPM, which on a plane will be for the majority of the cruise.

So maybe you can reduce the plane mass by a few percent, give it a bit more efficiency, but it doesn't change the fact that kerosene has 100x more energy density per kg than lithium ion. Electric drivetrains are already god tier in terms of power and efficiency, they just need an energy source that doesn't completely suck.

Every doctor's office having an MRI and terahertz processors that use next to no power will be very cool though, if this all pans out.


>I would be extremely sceptical that this would help electric planes all that much. Current brushless motors aren't really all that heavy for their kW output and already boast 90% efficiency at optimal load and RPM, which on a plane will be for the majority of the cruise.

The highest power brushless motors listed on Amazon are about 8kW (motorcycle hub motors). Superconductors could make possible a motor of the same size with approximately a 50kW output. The weight savings would be considerable.

Read this paper for more info - the paper also has a picture of a 5 MW high temperature (liquid nitrogen) superconducting motor, which is about the size of a car, and being tested for potential use in propelling large ships.

https://utw10356.utweb.utexas.edu/sites/default/files/Superc...


Lol, listed on Amazon. Look up some proper electric airplanes, e.g. https://www.pipistrel-aircraft.com/products/velis-electro

A 60kW motor in a tiny package. A single Tesla plaid motor can do a third of a megawatt. It's very doable without superconductors.


Another one: Lossless storage of energy.


How does this impact storage? Conduction (as in the superconducting) is charge flow, storage is generally static charge. Is this some sort of new storage system which somehow has a benefit by constantly moving charge? But wouldn't this generate losses due to the magnetic field interactions?


The fields do not interact in that way. When you move a normal electromagnet through a magnetic field, the electromagnet's field is affected because the the other magnet induces a current in the conductor. Possibly a counter-current, lessening the total magnetic field of the electromagnet.

That kind of induction doesn't happen in a superconductor. That's the Meissner effect - a superconductor rejects the induction of currents by exterior magnetic fields. I don't really understand the physics but, I think, the zero resistance is a property of a state of matter able to transfer electrons without electrons actually being involved. It's immune to normal electromagnetic effects.

Practically speaking, when you charge up an inductor made out of a superconductor, and then connect the two ends together -- the current cycles endlessly and the coil holds the magnetic field. It behaves like a permanent magnet you can turn on and off.

If you were to then apply a load to the terminals and break the loop, the energy held in the magnetic field will flow back out of the inductor as electricity.

It's already a thing, practically. Such systems have been built to load balance spiky transmission lines, etc. They fit into a unique niche somewhere between capacitors and batteries in trade-offs.


So you've not explained how this can be used as storage. Just because the conduction is free does not mean that the field interactions don't induce a load...


There is no induction, so there is no load.

Consider: why does a permanent magnet stay magnetized even in a changing magnetic field? Why do two permanent magnets stay magnetized when you bring them together and apart again?

When you move through the magnetic field of a permanent magnet, no energy is drawn out from the permanent magnet. All of the work occurred externally. It's the same with an energized superconducting electromagnet. Its field will not be "stripped away" by interacting with magnetic objects. The flux might be reduced if you brought an opposing magnetic flux near it -- but it would be increased again when you moved it back away. Net zero work.


https://en.wikipedia.org/wiki/Superconducting_magnetic_energ...

..but SMES has low energy density (but high power density).


This was great. Thanks.




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