Energy consumption at start of drive is insane.. anyone else?

  • SUPPORT THE SITE AND ENJOY A PREMIUM EXPERIENCE!
    Welcome to Tesla Owners Online, four years young! For a low subscription fee, you will receive access to an ad-free version of TOO. We now offer yearly memberships! You can subscribe via this direct link:
    https://teslaownersonline.com/account/upgrades

    SUBSCRIBE TO OUR YOUTUBE CHANNEL!
    Did you know we have a YouTube channel that's all about Tesla? Lots of Tesla information, fun, vlogs, product reviews, and a weekly Tesla Owners Online Podcast as well!

GregRF

Active member
Joined
Sep 25, 2017
Messages
92
Location
Aptos CA
Country
Country
#21
It of course depends on the circumstances - including, I should add, how long of a period of time the Wh/mi is spread over. Unless it's instantaneous that is (is it? Does it go negative when they decelerate? If so, how are they determining the average consumption - manually?). Any averaged energy consumption will reflect driving conditions, and driving conditions where you're generally going faster and faster with time mean you have to pay for that very large energy difference between being stopped and being at full speed. Note also that "multiple stops early in his drive" would be a bad thing from an efficiency perspective. Also note that I've been assuming 94% battery+motor efficiency!
The trip meter updates every tenth of a mile (so I guess it might get more accurate info in km!)

The meter does go negative. I live up a mountain road and if I'm not using much heat can get down the 3.1 mile road (5km) with negative energy consumed!
 

GregRF

Active member
Joined
Sep 25, 2017
Messages
92
Location
Aptos CA
Country
Country
#22
It was set to 72F and auto, it was 68F outside so not working too hard. These numbers are kind of ridiculous right? My lifetime energy consumption is 265Wh/mi over 1,500+ miles.
The Model 3 has a PTC heater which is self limiting by having increasing resistance as it heats up. But that means when the heater core is cold it has lower resistance and will have an inrush of current until it quickly gets up to temp. I'm guessing there is a big spike in energy at startup of the heater until it hits steady state.

Perhaps try your experiment again with the HVAC off to see if this variable is contributing.