There are two major mechanisms at work with a solar panel circuit. The production of “free electrons” and then the flow of the “free electrons”. Solar panels are basically special crystals that make the “free electrons” when they’re hit with sunlight. Once the ‘free electrons’ are produced, they flow through conductors to do whatever electrical work we want them to do.

The that special crystal is what is inefficient and it can’t be replaced with superconductors. Only the flow portion of this circuit could be replaced with superconductors.

I hope this helped, it’s a pretty simplified explanation.