“Now 80% of all the power we need comes from solar, including charging the EV.”
NICE! Just make sure that if the grid goes down, you still can use the power that your arrays generate, as that is usually NOT the case.
Correct. It depends on your state's regulations. In Alabama you can power your house with your solar and batteries even when the grid is down as long as your inverter(s) have the feature to not put power onto the grid when the grid is down. Not all inverters have that feature. But if your inverter has the feature to optionally not put power onto the grid (because your power utility would charge a large monthly fee, or if your state would force you to let them control your inverter settings, etc.), then chances are it also has the feature to not put power onto the grid if the grid is down.
The idea is to protect linemen working on downed lines, which is very understandable. My idea is to always be the one in control -- if I don't like the power utility's power buyback rules, I can turn it off without replacing my inverters. But if I like the rules and if they work best for my situation, I sign up for it (which I'm in the process of doing now after having solar for 2 years without putting power onto the grid and having power even the little bit the grid has gone down here). If my state changes the power buyback rules or mine an my wife's power consumption habits change so that the power buyback option isn't good for us, I'll disable it.
And it's a whole house system (using backup generator lingo). My inverters can put out up to 18kW continuous AC power (assuming I have solar and/or power in batteries). All circuits are powered from the inverters. So in a grid-down situation I might have to walk around the house to shut off some appliances (i.e. if I'm charging the EV at 5.6kW while it's below freezing outside and my home heater is running at 11kW while I'm in the hot tub using up 4 kW while my wife is cooking and using 7 kW, etc. would total beyond 18kW). But at least I could pick and choose at any point which appliances to power at that time (no dedicated circuits like with a lot of backup generator situations). In fact, from spring through fall I can go weeks in a row without pulling power from the grid even with the grid up the whole time (thus it's normal to power whatever I want without the grid).