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Actual wattage lower than planned? [on the utility PTO notification]

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Are you sure about that as Tesla inverters are either 3.8kw or 7.6kw?

My PG&E interconnect agreement from 2020 has my Solar CEC-AC rating listed as 7.556 kW and there is a footnote that says
CEC-AC (kW) = California Energy Commission Alternating Current, refers to the inverter efficiency rate (Quantity of PV Modules x PTC Rating of PV Modules x CEC Inverter Efficiency Rating)/1000
There is a CEC website that lists these values for all solar equipment:
I have 24 PV modules made by Hanwha Q CELLS model Q.PEAK DUO BLK-G6+/SC 340 which have a nameplate value of 340W, but a PTC rating of 318.1W.
My inverter is a SolarEdge SE7600H-US with Efficiency rating of 99%.

Plugging those numbers into the formula I get 24 * 318.1W * 99%/1000 = 7.5581 kW which isn't quite right. So I round down on the panel rating to get 24 * 318 * 99%/100 = 7.5557kW which rounds to 7.556kW which matches what Tesla submitted on my interconnect form. Maybe Tesla uses integer PV PTC ratings or maybe the value changed from 2020 to today.

I find this formula strange as there isn't any consideration for an undersized inverter that would clip the AC output. Also, for myself I have panels in four different directions due to my roof surfaces and the most that I will every get out of my inverter is 6.2kW, so my rating is far higher than I could ever produce.
 
I just got PTO on my 7.2kW system, but the PTO letter from SDG&E says congratulations on your 6.553 kW system. I know there’s some inefficiencies, but is it normal for the utility company to factor that in?
Hi, this literally just happened today with me and w/ SDG&E (same sized system as you, too). Did you ever find out the reason why? I guess I should reach out to Tesla?