We won't run out of room on the ground. Population will level off, and concentrate in cities. There will be no value in transmitting microwaves from space, bec

We won't run out of room on the ground. Population will level off, and concentrate in cities. There will be no value in transmitting microwaves from space, because we get plenty of light already. Eventually, aneutronic fusion will provide more convenient concentrated power. In the meantime, solar coexists nicely with farm crops and reservoirs, and we have many, many, many times as much of that as we would need to put solar onto, so it will only be on the best places for it, sharing with crops that get better yield by it. When the population in space is large, they will almost all be descended from other people already there. Very few will have moved out there.