There actually have been several solutions and some proofs of concept offered. However except for things like batteries, the purists object to all of them as gr

There actually have been several solutions and some proofs of concept offered. However except for things like batteries, the purists object to all of them as green washing. Why, I don’t know. Off the top of my head, I believe someone demonstrated you can add thermocouples to your water to generate electricity. The idea was that during excess electricity generation during the day by a homeowner’s solar panels, use that to heat up the existing water tank. At night, use the thermocouple to generate electricity from the hot water. Granted the efficiency is abysmal. But 5% of something is better than 0% which is what happens when the electricity is thrown away.