Tom Murphy wrote a good post on space-based solar a while ago: http://physics.ucsd.edu/do-the-math/2012/03/space-based-solar-power/ http://physics.ucsd.edu/do-t

Tom Murphy wrote a good post on space-based solar a while ago: http://physics.ucsd.edu/do-the-math/2012/03/space-based-solar-power/ http://physics.ucsd.edu/do-the-math/2012/03/space-based-sola... Either the power density is high enough that it roasts anything crossing the beam path, or it's low enough that it's not appreciably higher than regular old sunlight flux.