With 3 hours of free power, a 15kW inverter and a 42kWh battery, I could almost do away with my solar panels and just survive of free grid power. I do have a 15kW solar panel set up, but I get very little from selling anything back to the grid.
In winter, I’ve been using Ovo’s 3 hours free for about a year now and that ensures the battery is filled up daily. My electricity bill returns a credit every month since I got the battery a year ago.