[londons_explore]

Keeping things cold is effectively an energy vs space tradeoff.

For example, if you wanted to keep an underground superconducting wire cold, then you would send coolant pipes along it, and wrap it in an insulator. You need to put energy into chilling the coolant, inversely proportional to the thickness of the insulation.

However, typically for most things humans want to do, the cooling cost works out higher than the energy lost to resistance in a non-superconductor, so, apart from a few specialist use cases (MRI machines, particle accelerators), superconductors have seen no use.