We can't "harness one millionth of the Sun's power". Earth is only in the way of 4.35E-10 of all sunrays. You'd need a surface 2300x larger than Earth to do that...
Also sending that amount of energy to the earth would definitely cook it terminally, killing everything...
It is humbling to consider that if we harness just 1 millionth of the Sun’s power for AI, that will be much more than a million times the intelligence of all of humanity