Okay, so I went out to my usual Supercharger and documented what the car's screen displayed versus what the Tesla app showed for a charge from about 38% to 90%. Bottom line: Displayed cost changed from $16.22 to $15.20 when I disconnected, for a charge quantity of 36 or 38kW (depending upon where you look). Rate was $0.40/kWh so I'll go with 38kW delivered to the car (15.2/0.4 = 38). Contrary to all my previous data, the $1.02 difference is NOT an integer increment of $0.40; it's 2.55x. I sat in the car the whole time and did not run the climate system (I was listening to USB media). Temperature was 58F when I started and 63F at the end of the session (as indicated by the car's sensor). Here's some photos:
Car's screen just after hitting 90% and getting the Charging Complete message (note 36kWh added and $16.22 cost):
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Car's screen a few seconds later when the charging screen changed:
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Car's screen earlier in the session showing 85% charge (note 41kW charge rate and 32kWh added):
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Tesla app showing 85% charge a few seconds later when the app updated to 85% (note 47kW rate, the 32kWh added and the heating? [3 S's] icon on the battery line):
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I noticed that throughout the charging session the difference between what the car said was being delivered was 6-7kW
lower than what the app indicated. However, the charge added to the car (kWh) was identical.
Tesla app charging history showing today's session (note 38kWh figure):
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And the invoice (again showing 38kW):
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@AlanSubie4Life Is this enough info? I do have a series of photos and screen captures from the app during the entire session.