We currently have 2 solar PV 240VAC circuits(3.5kW) back feeding the grid by day on NEM1 but that'll change in early 2025 when we get switched to NEM3. Here's the plan I've come up with so far using 2 Victron MultiPlus II 48/5000/50 inverter/chargers and a Victron Distribution module with 2 15 kWh Bassen Green battery packs.
For the DC side I'll wire batteries together then to the Victron Distribution module and wire each Victron MultiPlus II to the Victron Distribution module.
For the AC side the Victron inverters will be in multi-phase configuration with AC1/primary outputs wired to a 240V subpanel. I'll move the 240V grid-tied solar back-feed circuits to this subpanel along with house load circuits and configure the Victrons for zero back-feed( ~100W ) with all solar generated energy going to battery charging.
I will have our HVAC and EV charger and a few other circuits on AC2/secondary AC output of the Victrons in the existing Mains panel.
I only charge the EV on 240V/20A circuit(16A) and the HVAC is on a 240V/30a circuit.
Our low daily load is 5-7 kW without power tools, HVAC, dishwasher, etc.
Does this sound like a sound design?
