Does that efficiency figure fit with footprint though?

As in, Solar may be 12x cheaper per kW but requires 20x more spaces so the argument isn't quite so easy to make? I had always heard that the problem with Electricity in general is shipping it from empty spaces where you could build vast solar arrays to populated regions, but I'm not sure if that's just a lie OPEC sold me.

I don’t see where 12x number is coming from and what are the error bars on it. It looks like depending on the source (i.e. France) nuclear energy is considered to be competitive with solar installations.

Numbers are from the pdf in the link. There is a table with cost per kW installed and maintenance per kW.

Grid interconnection is a huge problem for the centralized generation of solar. Most plans call for a microgrid strategy where rooftop solar plays a huge part. Microgrids eliminate huge costs in terms of grid maintenance and transmission, which is currently 60-90% of the average electricity bill.