[cestith]

Cleaning the reflectors may not be a trivial engineering task but neither does it seem insurmountable. Ultrasonic or electrostatic techniques come to mind. Maybe titanium dioxide plays a role as in self-cleaning window glass. If some sort of mechanical action is needed, it has a whole night to complete cleaning before the reflectors need to be ready again.

Heat mass plants provide storage as part of their electric generation process. That's the whole purpose of transferring the heat into the heat mass rather than directly to the turbine loop.

[Retric]

The problem is it isn’t free.

PV extracts more electrical energy per area of solar collector and it isn’t cost effective to clean them or currently to track the sun. Concentrating solar takes a larger hit when it skips either, which is just one of the reasons it’s not cost effective.