I did an experiment with Sentry mode last week and thought I'd share the results here.
I flew to Sydney for a business trip on Sunday the 20th and returned on Friday the 25th. I checked in on the car each day and took a screen shot to record the state of charge. Here is the data with the assumption the battery is 79.5 kWh as per EVSpecifications:
Feb 20, 10:32, 61%, 48.5 kWh
Feb 21, 13:44, 56%, 44.5 kWh , ~147 W consumption
Feb 22, 07:44, 53%, 42.1 kWh, ~133 W consumption
Feb 23, 10:26, 46%, 36.6 kWh, ~206 W consumption
Feb 24, 11:24, 39%, 31 kWh, ~224 W consumption
Feb 25, 13:38, 30%, 23.9 kWh, ~273 W consumption
Feb 25, 19:44, 29%, 23.1 kWh, ~133 W consumption
There were 50 Sentry mode events during the entire period. I've not looked at them, so not sure of the activity spread across the days. I also realized that I had the cabin heat protection mode with AC set to on, so that might have fired up at some point.
My car is a 2020 Model 3, Performance. It would be interesting to see if the new 2022 cars are more efficient?
On normal days that I travel from the Gold Coast to work in Brisbane I would use about 20% each way. Unfortunately that calculation went out the window when we arrived in Brisbane and it was raining heavily. Adding my wife and luggage to the equation was not helping either. Thus, soon after the Gateway Bridge the car was complaining and asking me to drive below 90 km/h. Then after the M3/M1 merge the car was saying we would not make it home and to drop speed further. I changed the destination to Helensvale Railway Station, thinking I could get a quick top up there and kept going at 90 km/h. With the rain starting to ease as we headed south I tried dropping the speed to 85 km/h and set the destination to home. The car said we would arrive with 3%.
I stuck to the left lane and kept the car set to 85 km/h for the rest of the journey. Surprisingly I still had to pass a couple of cars that were going slower, presumably because of the weather. I kept asking my wife to check the navigation status and it dropped to 2% and then 1% during the trip. I turned off the A/C once we got on Smith St. and accelerated very slowly from any lights. Thankfully we made it home without needing a charge and 1% left.
Even at those low speeds the consumption was 205 Wh/km with a normal trip to Brisbane and back using ~165 Wh/km.
Lesson - Charge to 100% before going to the airport if you want to use Sentry Mode
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