It's all about grid capacity and efficiency, not personal cost savings. Think about rooftop solar from the utility perspective. On peak load days in the summer,

It's all about grid capacity and efficiency, not personal cost savings. Think about rooftop solar from the utility perspective. On peak load days in the summer, they will have a more stable grid when AC units are being offset in real time by the very sunlight that is causing them to be needed. Even a cheap 1kW system with no batteries on every house would make a massive difference.