I have a dumb question about the efficiency of an inverter AC, such as a ductless mini split. Basically, my question is in general at what capacity is an inverter AC generally most efficient? I am sure the answer will vary a bit based on the design of the specific unit, but what would be “typical”? I have not been able to find any efficiency curves at different capacities, or any actual data on efficiency at different capacities.

I have heard that the unit’s efficiency is highest when the unit is running at the lowest speed because the heat exchangers are largest compared to the unit’s capacity. This makes sense to me.

However, I have also heard that the unit doesn’t operate very efficiently at minimum capacity because the compressor is inefficient below a certain capacity, which also sounds reasonable.

So in general, which would be correct? Or would the unit’s best efficiency be somewhere between minimum and maximum capacity? Thanks in advance, I have been wondering about this for a while and I have not been able to find any answers