A Fridge that was solar power aware could absolutely freeze a big chunk of water or another material that was more energy dense with diverted solar power and then use it as cooling through the night when solar wasn't available. The same is true of water heaters (for which we have diverters already available) for storing hot water and a bunch of other devices like ceramic heaters.
A lot of these appliances exist already for shifting power use to the sunny hours based on electricity, but right now all the various parts don't really work together as the home grid is just dumb AC and people orchestrate it all with Home assistant where possible.