Numerous Model S' seen not running AC on hot Ontario day

[navguy12]

I will preface this with stating that this information comes from my brother.

He just informed me (via our regular weekend phone call) of the following observation he made last week.

He, along with three other chaps driving four vehicles from one wholesaler location in Toronto to another in the Ingersoll (Ontario) area were on highway 401, during a very hot and humid day.

"We say numerous Tesla's over the course of the seven hour work day. Every one of them had all the windows wide open. If it was only one or two, you could dismiss it. However, 'ALL' the Tesla's we saw were running on an extremely hot day with all the windows open".

He continued, "I know you love those cars (I plan to buy a Model 3) but they must be loosing too much range while running the AC. There is no way I could buy a car and then not be able to run the AC on a trip because it's either too hot or the range is too short....."

And on the anectodal evidence went.

Anyhow, I would like to hear some folks pipe in and answer what could have been a motivation for "all" Tesla's seen that hot afternoon on the 401 driving with all the windows open.

Thanks

Cheers

Mike

 

[wycolo]

Were they dicing and slicing back and forth, shouting at one another?
--

 

[Lesifass]

He continued, "I know you love those cars (I plan to buy a Model 3) but they must be loosing too much range while running the AC. There is no way I could buy a car and then not be able to run the AC on a trip because it's either too hot or the range is too short....."

Depending on speed / drag coefficient, driving with AC instead of open windows will actually improve range. Open windows kill the drag coefficient, so at high speeds it's a range killer.

 

[navguy12]

Were they dicing and slicing back and forth, shouting at one another?
--

I've emailed my brother to ask that specific question.

Had the Tesla's been driving as you described, my brother would have simply regaled me with a story of all the "idiot Tesla drivers doing supid things all over the road".

 

[navguy12]

Depending on speed / drag coefficient, driving with AC instead of open windows will actually improve range. Open windows kill the drag coefficient, so at high speeds it's a range killer.

Thanks for the observation. I am aware of the issue of drag, open windows and hi speeds. So it goes back to the core question, why would they be doing it?

 

[deonb]

The Model S A/C uses almost nothing compared to the energy required to move the car. You can literally run an A/C at full blast for 60 hours from a 85kWh battery.

Also, you don't save energy by running without an A/C and open a Window. The Model S is highly streamlined. The effect of drag on a Model S with the windows open is MUCH worse than the cost of running the A/C.

 

[navguy12]

Were they dicing and slicing back and forth, shouting at one another?
--

My brother just got back to me, saying it was individual cars....over more than one day period. I've asked him, any chance it was the same car you saw at different times over the time period (i.e. same color).

 

[navguy12]

The Model S A/C uses almost nothing compared to the energy required to move the car. You can literally run an A/C at full blast for 60 hours from a 85kWh battery.

Also, you don't save energy by running without an A/C and open a Window. The Model S is highly streamlined. The effect of drag on a Model S with the windows open is MUCH worse than the cost of running the A/C.

Ok, I'll pass that on. That makes total sense to me. Thanks.

 

[deonb]

So it goes back to the core question, why would they be doing it?

Maybe they didn't pay attention in physics class.

 

[SSD420]

I have a Model X. I run the AC virtually every single time I drive. Sometimes just the cooling seat option. Only when I did a range drive was I a bit more conscious of having my fan. Don't worry about running the AC @navguy12

 

[navguy12]

I guess I could track down that range calculator on the Tesla site. I'll punch in 30C as the temp, 120 kph as the speed and see what effect on range, theoretically, the use of airconditioning will have.

 

[SSD420]

*having my fan on a lower setting

 

[Hodginator]

Maybe they like to drive with the windows down and it is as simple as that...

 

[kort677]

the affect on range (which is small) of using the AC is far outweighed by the comfort afforded by using it. I don't want the wind noise at speed and I want to be comfortably cool. even if I choose to open the window and roof at lower speeds I leave the AC on.

 

[liuping]

Heating definitely effects range, but AC not so much.

Check the "Range per Charge" calculator on this page: Model S | Tesla Motors , you can toggle A/C on and off to see the effect on range.

For example: driving a 70D at 70 MPH with AC on when it's 90 degrees Fahrenheit outside, drops the range from 253 to 244 miles range.

 

[DMC-Orangeville]

I might have been one of them.I love to drive with windows/sunroof open on hot days.

 

[navguy12]

Heating definitely effects range, but AC not so much.

Check the "Range per Charge" calculator on this page: Model S | Tesla Motors , you can toggle A/C on and off to see the effect on range.

For example: driving a 70D at 70 MPH with AC on when it's 90 degrees Fahrenheit outside, drops the range from 253 to 244 miles range.

Done. Just throwing a crude summary here:

My assumptions are 120 kph, 30C temp. Range penalty is between 4.5% and 4.8% (13-19 kms).

I concur with everybody's reply's here. I'll ask my brother again how many he saw, etc. I just find it interesting that every one he claims he saw had the glass down on a very hot day. Cheers .

 

[navguy12]

I might have been one of them.I love to drive with windows/sunroof open on hot days.

OK, I'll let him know. Cheers.

 

[jerry33]

I generally have the windows on one side open 3 cm when it's below 30. This does not affect the windstream enough to make a difference. Above 30 and it's AC time. However, I would probably run the AC at lower temperatures in Toronto since it's very, very humid there.

 

[thecloud]

Maybe these cars were experiencing an issue reported here previously, where the A/C was being diverted to cool the battery?

Air Conditioning Blowing Hot Air
A/C Fail with last night's Software Upgrade?