Overall Efficiency of MPPT Charge Controller vs. Inverter vs. Combo Units (Off-Grid)
Is there a general consensus on how to build the most efficient off grid system? I see these 90+% efficiency specs, but I am not sure how to compare them to determine the best option:
1) MPPT Charge Controller + Inverter as separate units tied together via the battery bank (do I multiply their efficiency percentages) vs.
2) A combo MPPT Charge Controller - Inverter unit. Does the efficiency spec mean solar output to 110V AC efficiency?
Also, is there a general rule that combo units are more efficient? I am also wondering if there is difference in efficiency in using the AC electricity as it is being generated in the day vs the conversion to battery energy then back to AC via the inverter at night. I suspect that the roundtrip to the battery probably wastes some energy.