The most modern of these use molten salt systems with the ability to store heat for overnight power generation:
https://en.wikipedia.org/wiki/Ouarzazate_Solar_Power_Station
Waterless robotic cleaning is possible:
“It uses a waterless robotic technology to clean the solar panels. The robots travel a distance of 1600 kilometres every day to clean it.”
https://en.wikipedia.org/wiki/Noor_Abu_Dhabi_Solar_Power_plant
Solar and Wind are purported to return 5 times the energy invested. That is equivalent to cutting and burning cord wood.
You can’t have a modern civilization with that type of return.