Help me understand kWh used

[bell2041]

This is a 75D Model X. So my math is 100% is 75kWh, my last charge was up to 90%(67.50kWh), now the car at 55%(41.25kWh) so "Since last charged kWh" should be 67.50-41.25= 26.25kWh, but it says 19.90kWh

Thoughts?

 

[P85_DA]

That number is only your driving usage ..not sure if u have cabin overheat on etc ...vampire drain from car sitting there is also not counted in that number

 

[bell2041]

so you mean that 19.90 kWh used only for driving? not including AC/Heat use when car is parked, etc?

 

[skraid]

so you mean that 19.90 kWh used only for driving? not including AC/Heat use when car is parked, etc?

Exactly

 

[dethman]

that's a lot (7kwh) of extraneous drain.

 

[P85_DA]

~13-14 miles not bad ...OP didn’t say how long car was sitting etc

 

[eladts]

Also, 75kWh is the nominal capacity of the battery, not the useable one. There are buffers above 100% and below 0% to protect that battery.

 

[Uncle Paul]

75 battery is slightly less than 75. Think it more like a 73 or so, rounded up to 75>

 

[animorph]

Many many threads on this. My favorite answer is that you get more energy out of the battery if you take it out slowly. So your calculation should look closer to advertised capacity if you just travel at 25 MPH steady-state. And the kWh added during charging will probably be closer to the real battery capacity than the kWh measured coming out of the battery, which will depend on how you drive. One reason is the internal resistance of the battery. The more current coming out of the battery, the higher the internal losses, which are not captured by the measurement you are seeing.

 

[animorph]

Here's a nice graph:

Car’s energy consumption (lack of) accuracy

Notice how the calculation gets better (around 96% match) when the consumption rate is low, but worse (82%) when consumption rate is high.

 

[hill]

that's a lot (7kwh) of extraneous drain.

I've seen worse, especially during updates. And for the OP, don't forget (or, fyi) your 75 Tesla does not actually have 75kWh's usable - even if it were brand new straight off the manufacturing floor. iirc, it's ~72kWh.
.

 

[bell2041]

I like to leave my car with "keep AC ON" (for like 10-15 minutes at a time), so I wanted to find out how much does AC actually uses, I guess it's 7kWh

 

[unpollo2]

I like to leave my car with "keep AC ON" (for like 10-15 minutes at a time), so I wanted to find out how much does AC actually uses, I guess it's 7kWh

i do this all day i'm out, i find it is very efficient like 3 miles an hour drain, but i set the fan to 3 or 4 and recirculate on