[BjoernKW]

This is where superconductors come into play, i.e. materials that allow you to move electricity at no loss due to electrical resistance. The problem with those (traditionally, at least) has been that they usually operate at very low temperatures, which of course again require energy to be maintained.

A room-temperature, ambient-pressure superconductor would be the breakthrough required for doing this at scale. This of course would still require significant infrastructure investment.

[imtringued]

A room-temperature, ambient-pressure, non-ceramic superconductor would be the breakthrough, because you need your superconductor cable to be transportable, repairable and not be a kilometer long piece of ceramic with zero tolerance for defects.