When going for serious global scale stuff you put the panels in sunny places and run gigantic cables to the places it isn't sunny. Again, possible to do but massive scale infrastructure projects that take time, money, and political will.
No. 1-2MV DC transmission lines can move power 3000+ miles at >97% efficiency.
This isn't directed at you, but I'm starting to get super frustrated with this myth that transporting electricity is inefficient. I see it almost everywhere these discussions take place and I don't know why.
I suppose efficiency aside, the next big problem(s) would be of a political nature? Having no control over your power supply (which is hosted in a foreign nation) is quite a big geopolitical risk?