It's worth noting that the common complaint about systems like this, which is that they could cause dangerous conditions during power outages when people expect the power lines to be unpowered, is addressed by electronics that only feed power when they detect an active mains.
All solar inventors connected to public electric grid have to detect this state and disconnect. You are not allowed to connect arbitrary inventors to electric grid, they have to be compliant with IEEE 1547, UL 1741.
