Beyond that, what about collectors on the far side of the moon? Much larger area to play with, then store or send to near side for transmission to earth. And no problems about being seen from here.

But I think that wind and wave energy will be much bigger than people think, and sooner rather than later, in any case.

codemaniac

As Criswell noted, you can design the receiving antennas to have net neutral heat flow: by painting them white to reflect sunlight, for example, they can be balanced with the incoming energy on average so there’s no net change in retained heat.

In any case, even without the balanced design, the heat flow involved is about a factor of 3 less than the extra heat flow caused by any non-renewable electric power plant: nuclear or fossil-fuel based plants are only about 34% efficient in converting the heat of burning to electric energy, and nuclear or fossil fuels are just as “external” to natural heat flows as additional power beamed from space.

But even that heat flow from “burning” is miniscule relative to the additional retained heat caused by the CO2 and other greenhouse gases themselves. After the heat release from burning, the CO2 that remains in the atmosphere acts to enhance the heat retained on Earth’s surface from sunlight – that heat retention amounts to (depending on the level of greenhouse warming expected) about 300 times more than the initial heat release from burning.

So our energy imports from space would have to be about 1000 times greater than current energy usage to have the same 2-degree warming effect that we’re getting from all the CO2 we’re releasing – assuming that with all that energy we can’t find good ways to balance things out.