When people propose the "cover 150,000 km^2 with solar cells solution", I like to see them go on the record as saying that if we actually tried, they would not immediately turn around and start screaming about the 150,000 km^2 of Mother Earth we just converted to industrial land.

Solar of any form has a major power density problem. At least, it does in the biosphere, which it should be observed is only a rather small percentage of the universe....