Feeding large amounts of excess PV solar-generated power back to the grid is problematic because neither the grid nor most residential solar installations have

Feeding large amounts of excess PV solar-generated power back to the grid is problematic because neither the grid nor most residential solar installations have any storage capacity. If you return power to the grid, it must be used somewhere else immediately. As I understand it, peak PV generation times don't coincide with peak grid demand times.