"This is complete utter nonsense. A quick back-of-envelop calculation: The sun has an angular diameter of 0.0093 radians, so "focusing" the sun's rays from a distance is optically impossible"
Hmmm - never heard of parabolic reflectors???
It is perfectly possible to make a parabolic reflector that has a focal distance of several hundred kilometres. Besides, it has already been done - see the earlier reference in these comments to the Russian experiment.