This video describes an off-grid solar charging system that I built for my Tesla. It consists of 8 Battle Born batteries (~10kWh storage), a 100A Victron charge controller, two 24V Victron Multiplus inverters, a Victron smart shunt/battery monitor, and a Victron Cerbo GX brain. The system is powered by 16 monocrystalline 320W panels, 4 parallel strings of 4 series connected panels.

The system is capable of charging the car at 4.8kW continuous, 240V split-phase. The maximum PV input is 2.7kW, limited by the single 100A charge controller.

Discharging at 4.8kw results in a 183A draw from the batteries w/o solar input. This equates to 45A draw from each of the 4 battery banks, or roughly 1/2C. This is OK, but not great for the batteries. Therefore it should only be done when solar array is fully operational to limit battery discharge rate.

I typically charge the car at ~2kW, manually setting the charge current in the vehicle to 9-10A. This results in an inverter efficiency of ~90%. If I charge slower at the minimum 5A, the inverter efficiency improves to 96%.