I just did the math, it works out! What we need to do is move the aluminum reduction cells into floating solar powered processing units which drift around the

I just did the math, it works out! What we need to do is move the aluminum reduction cells into floating solar powered processing units which drift around the world receiving aluminum oxide from drone craft and deliver refined aluminum back to them. It will take 59 kilojoules per kilogram to raise the ore to 6km, times the inefficiency of the craft, lets say a number less than 10. Plus, aluminum oxide is only about half aluminum so another 2, lets call it 1 megajoule per kilogram of aluminum in round numbers. Refining aluminum oxide into aluminum takes 54 megajoules per kilogram of aluminum! (according to a number I found on the internet and most probably read correctly). That makes the energy to raise the aluminum negligible. So forget about how to transmit electricity down from the solar pelagic behemoths drifting lazily around the planet, just use them to refine aluminum. Ships of aluminum oxide will cruise out to the behemoth orbitals and track them while they exchange their cargo for refined aluminum. Presumably a sufficiently clever person will find areas in the Pacific ocean where the behemoths can lazily circle by gently pushing themselves from eastward to westward currents using altitude variation which is easy by controlling how much inventory is onboard, but also by how much waste heat you put into your gas bags. Sure, once in a while they will be blown away on longer excursions, that will take them offline until they can get back over another drone supply ship. This is the future science fiction has been promising me!