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Average kW/M or kw/KM mileage?

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Hi all,

Since my car is a company car, I need to report my mileage every now and then, just as my ICE colleagues. There's only 1 problem: there's no data to compare my usage with.
Here's a quick graph of my usage during the last few months:

I'm seeing an average of about 200Wh/km at the moment, which would be around 320Wh/Mile.
useage.png

This is based on OVMS odometer logs and charge card data.


So I would like to know: What are your average mileages... kWh/km, kWh/Miles.
Thanks all!
 
EDIT: The below is referring to the Model S, not Roadster. Tried unsuccessfully to delete post.

There's no easy way to do this properly. The Tesla displays only show how much energy comes out of the battery when the car is running, not how much energy you put in to the car.

The car has charging efficiency losses meaning that not all of the input power makes it to the battery and gets converted back from chemical energy to electrical energy when you use it. An analogy would be like spilling gasoline when you fill your car (you still pay for the spilled gas).

The car also has standby losses that are not accounted for in the car's displays. These are sometimes referred to as "vampire" losses, and a gas car analogy would be like having a small leak in your gas tank.

What I do, and it's a lot of work, is meter all of the electricity I put in to the car at home with a separate sub-meter on my EV circuit and I also carefully record how much power I put in to the car at public stations.

I typically calculate around 30 to 40% greater consumption (Wh/mi) than the car's energy meter reports for the same period. I do this monthly. It will vary depending on your driving habits (how often the car is charged, how long it is parked, whether you have Energy Savings On or Off etc.)
 
If you pull the logs, you should be able to get all the charging and driving information, at least for the last little while. Seems like it'd be easy to compute based on that information, although the energy used to charge might not match the energy used to drive due to some energy loss in the charging process.