[Chris2048]

Surely sunlight is less filtered above the atmosphere than below/in it? Also, maybe microwaves pass through the atmosphere with less absorption?

The current plan for solar power stations entail using mirrors to focus it to one spot anyway, so the evolution of that might be space mirrors that convert it to a single frequency before beaming it down to a focal point.

Also, the panels/mirrors can be sun-synchronous to receive sun all the time, reducing the amount of them needed (surface panels would not get peak sunlight all the time, and half the time will be shadowed by earth).