The article mentions that the solar plant produces 110MW, which I presume is the thermal energy captured. On average converting thermal to electric is about 1/3 efficient so this two-mile-wide field of mirrors, all of which require electric motors, maintenance, and regular cleaning for actual operation, will produce maybe 40MW of electricity? How many megawatts would be generated if all of those mirrors had PV panels installed instead?
> 110MW, which I presume is the thermal energy captured
That would be deceptive advertising. 110 MW is the "nameplate capacity" which is basically its maximum sustainable generation capability. Its storage capacity is specified straight-forwardly as 1,100 MWh (electric)
that is one of the primary points of the system; You can generate molten salt when the sun is out, and genereate the electricity via a steam turbine whenever you want.
This gives you the possibility to use this technology as a buffer.
Perhaps a hybrid system would be the best compromise: use PV panels to capture electricity, but keep some salt molten using a combination of electrical heating and solar energy redirected off the panels' protective coatings, then at night you can supplement your batteries with the far longer lasting molten salt.