Solar power systems have at least one thing in common with other large-scale power generating systems- they have to handle large amounts of energy in a controlled manner, and when the controls fail bad things happen:
Note that the heliostats are under computer control, and many of them had to have been simultaneously off-target in the SAME WAY to do the indicated damage.
Software glitch? Terrorist hack? That nobody was in the part of the tower that got torched looks to be pure dumb luck. Also, I wonder if hiking in the mountains in the background is restricted?
Mark L. Fergerson