Breakthrough discovery of the one-way superconductor? (opens in new tab)

Any real fusion reactor would need 5+ T confinement fields and be 2+ times the radius of this machine. You would be using many GW in ohmic losses in copper confinement coils for hundreds of MW of fusion power: it simply could never work. A cryoplant for an LTS fusion reactor would use on the order of 50 MW, a bit less for HTS.

So for the big magnet application superconductors are an incredible win.

Not a thermals guy, but bog-standard, consumer air conditioners tend to have efficiencies of 300% or so. Ie, for every joule of electrical energy consumed, they'll reduce the thermal energy in the room by 3 joules.

Regardless of this, having zero heat output in the wafer itself could be far more interesting than just increased power efficiency. For example, without the issue of thermals one could imagine silicon wafers with thousands of layers and 3-D interconnects.

So you're only really fighting the inefficiency of your insulation, and insulation can be very, very good (at the extreme end you could magnetically balance something in a vacuum chamber and then chill it - it'll take a very long time to heat up by radiative emission from the walls (double wall insulated cups use this property though my take is they're just gas filled - same idea though).

Essentially the ongoing cost of keeping something cool is purely a function of heat load making it through insulation, and in all cases that's going to be much lower then generating heat in the system - the problem is that engineering and complexity wise, it's non-trivial and failure scenarios can be bad - i.e. an SC magnet quench can be very bad since you amongst other things might immediately boil your coolant. This happened at the LHC during commissioning.

but maybe... bottom of the ocean? space/moon ?