[GistNoesis]

I did a quick search on the Energy Returned on Energy Invested calculations. The following site https://dothemath.ucsd.edu/2012/03/space-based-solar-power/ gave an ERoEI of 10:1 for solar panels on earth vs ERoEI of 4.2:1 for solar panels in space. Which would indicate that we would still be better laying solar panel on the ground as long as we got the appropriate empty space.

What did I missed? Have we realized enough progress since 2012 energy-wise, that the threshold has been crossed, or does it only make sense economically due to lower launch prices.

[adrianN]

Solar panels in space also work during the night and while it's cloudy. Did your calculation include the energy costs of storage?

[AstralStorm]

You do know that one can build the panels on the other hemisphere, right? It is all a small matter of building a long enough high voltage DC line. Mostly a political problem. Or you can use microwaves on ground if it is easier to build a bunch of antennas.

Ultimately also reflect off space mirrors (meshes) for much cheaper.

The main problem is theoretically weather. Space has the other kind of weather called space junk.

[adrianN]

HVDC lines are really neat tech and I fully support solar farms in the Sahara to supply Europe, but I wouldn't be surprised if it's cheaper to launch satellites than to build a global power grid that can provide solar power over night.

I think debris is not a terrible problem right now. We manage to have a large number of satellites in high orbits.