I have a solis inverter and it comes with a load out socket, which can be connected to a standard uk socket.
My installer contacted me to say that he can now install from this connection some feeds to say the lighting circuit, it can’t go to your consumer unit but a separate unit with a connection between the two, there has to be a safe way to switch either auto or manually or things will sizzle and burn.
It works only if a battery is installed which I have, but I wish it was bigger.