Anyone interested in Temp vs energy consumption charts?

[Fourdoor]

I just went to the trouble of compiling my daily commute data from the first 6 months of owning the car. I used Teslafi data and then edited out anomalous data (different average speed than normal). If you use teslafi, it gives a nice "temp vs efficiency" chart, but that is not controlled for vehicle speed. The data I used is for my daily drive where I take the same route at the same speed each day.

For the first month of ownership I was on the stock 21" wheels and summer tires that came on the MYP, after that I am on a set of Gemini 19" wheels and OEM all season tires. Driving conditions are 60 mph peak speed with an average speed of 50 mph with climate control set on 70F auto.

Later,

Keith

 

[Puma2020]

This is interesting. Thanks. However it is not really showing efficiency but instead how the Y uses more power in the colder temps than in the warmer temps, although above 85 or so, appears to show more energy used as well. Since cold air is more dense, it does that more energy to push through it. Also as the temperatures rise (above 80) or fall, the Y needs to use some energy to heat or cool the cabin and/or heat the seats. Plus having the data on the 21" wheels .vs. 19" wheels provides more data to ponder. It is interesting data.

 

[Johnny Vector]

Impressively linear! Nice measurement of the overall combination of effects. Thanks for the data. Typo alert: The y axis of the first graph should be watt-hours per mile!

 

[GtiMart]

For those that have TeslaFi, there is a Temperature Efficiency graph available that shows similar information.

 

[Fourdoor]

For those that have TeslaFi, there is a Temperature Efficiency graph available that shows similar information.

I pointed that out in my original post, but that graph takes no account of vehicle speed. If you only drive local all winter at 55 mph or less for your commute, but in the summer you make highway road trips at 80+ mph then it will skew the results to show you are more efficient in winter temperatures and less at summer temperatures. My results are for the same route at the same speed for each data point.

Keith

 

[Fourdoor]

Impressively linear! Nice measurement of the overall combination of effects. Thanks for the data. Typo alert: The y axis of the first graph should be watt-hours per mile!

Oh $hit! Don't tell querdna!

Keith

 

[ThePirate]

Thank so much for taking the trouble to publish that. Really appreciate it!

Between 65 and 35 F your "W/mi" [sic] went from 250 to 280 roughly, an increase of roughly 12% for let's say 40-60 mph driving. That's great! That won't amount to an extra stop for me when I go skiing (should I ever get my car, sign...).

Now people on youtube report really horrific winter efficiency, so I can only conclude that they are going 70 mph, a very different test, and that efficiency somehow drops a lot more at higher speed. Does anyone have any data on that? (someone above said air is denser, friction is maybe v^2, so maybe that's it???) I'm not going to admit I speed, just a theoretical academic curiosity, you know...

 

[GtiMart]

@Fourdoor , there's a separate speed graph in TeslaFi. But you are correct, the two aspects are correlated. In my case with harsh winters, the speed graph doesn't work because of wide temperature differences.
Note that the TeslaFi graph lets you pick a minimum of say 25 mile drives. In such cases, you are already filtering only highway drives. If you commonly drive at the same speed all the time, you eliminate the speed factor for the most part.

 

[T.J.]

Thank so much for taking the trouble to publish that. Really appreciate it!

Between 65 and 35 F your "W/mi" [sic] went from 250 to 280 roughly, an increase of roughly 12% for let's say 40-60 mph driving. That's great! That won't amount to an extra stop for me when I go skiing (should I ever get my car, sign...).

Now people on youtube report really horrific winter efficiency, so I can only conclude that they are going 70 mph, a very different test, and that efficiency somehow drops a lot more at higher speed. Does anyone have any data on that? (someone above said air is denser, friction is maybe v^2, so maybe that's it???) I'm not going to admit I speed, just a theoretical academic curiosity, you know...

From what I’ve read, winter driving at colder temps isn’t as much of an issue of battery efficiency but of what your energy is used for. Assuming the battery is preconditioned. ICE vehicle efficiency is stated around 60% energy used for driving and the rest is just latent heat. The heat recaptured for cabin heating is functionally free. In an EV, electric motors are very efficient, in the high 90% and heating the cabin with a heat pump or even worse, resistance heating, results in a noticeable use in energy. This results in a higher energy use as the temp drops. This has been my experience.

 

[Fourdoor]

@Fourdoor , there's a separate speed graph in TeslaFi. But you are correct, the two aspects are correlated. In my case with harsh winters, the speed graph doesn't work because of wide temperature differences.
Note that the TeslaFi graph lets you pick a minimum of say 25 mile drives. In such cases, you are already filtering only highway drives. If you commonly drive at the same speed all the time, you eliminate the speed factor for the most part.

Good point there, I never looked into the filters available on the temp vs efficiency graphs... I still like temp vs energy consumption graphs better though

Keith

 

[Fourdoor]

From what I’ve read, winter driving at colder temps isn’t as much of an issue of battery efficiency but of what your energy is used for. Assuming the battery is preconditioned. ICE vehicle efficiency is stated around 60% energy used for driving and the rest is just latent heat. The heat recaptured for cabin heating is functionally free. In an EV, electric motors are very efficient, in the high 90% and heating the cabin with a heat pump or even worse, resistance heating, results in a noticeable use in energy. This results in a higher energy use as the temp drops. This has been my experience.

Yup.

This is why my thread is title says "Temperature vs energy consumption" instead of "temperature vs efficiency". I named the thread this way for a reason If you do a word search on this thread you will see that the only place I used the word efficiency was in reference to the graphs available on Teslafi... and in this reply

Keith