Interpret the operating expenses in the Cash Flow Results

Hi there,

My SAM version is 2020.2.29. I find it's difficult to interpret the total operating expenses ($) in the cash flow for the SAM project attached.  

I created a fixed-tilt PV+AC system with the SDG&E time of delivery schedule. After the simulation, in the Cash Flow file, I am assuming the total operating expenses equals to all operating related costs: O&M, battery replacement, property tax expenses, and insurance expense. However, the total operating expenses are significantly higher than the sum of all costs.

The Year 1 total operating expenses are over 4 million while the sum of all operating expenses is less than 2 million. It seems the number difference only applies to this specific configuration. PV+DC, PV only, PV+AC with uniform TOD do not have such a significant difference.  
It would be helpful if anyone can help me find/ calculate it. Thanks.

Thanks, Paul.

I think I used the older version (2020.2.29 without the revision), thus missing the electricity purchase row. The revised version makes sense.

Best,
Kai