Your "physics" based comment seems to hinge on the totally invented axiom that the solar needs to provide all the power, rather than just contribute some in a way that is cost effective and/or more convenient.
Imagine wearing a Garden Cress hat 24/7. It grows fast and new batch is ready to be eaten every 2-4 days. Thats ~10 calories for free per day, FREE sun energy! Hat weights a pound and you cant take it off, even at night.
We seem to be moving further away from "physics" based reasoning with this analogy. Do trucks not like wearing hats? Do they get crushed against their pillows when they sleep?
All this time and I never realised Pixar's Cars has been spreading misleading physics.