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Speed vs Temperature effect on range - graphs for your info

I lifted the data points from the "How far can I go" page on the TM site and plotted the graphs below. The first one shows the impact of speed and temperature on range with no A/C. The second is with A/C - both cooling and heating.


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I know Cliff Hannel is working on a range calculator. Until then hope this is useful.

Wow. Wouldn't it be great if these graphs and the underlying data were used in the Nav and Energy apps to calculate real world ranges rather than fictitious ranges? Shouldn't be that hard. Maybe Tesla should open up the APIs to OSS developers who could get this done in no time.

I wish these and similar charts and calculators would not all end at the (to European standards at least) very slow 65mph. I live in the Netherlands, and while we do have some parts of the highway where the speed limit is 65mph (during the day), our general highway speed limit is 80mph, and my cruise control will typically be set at 90mph for long stretches of time. Those are the kinds of speeds that the range would _really_ matter to me. Speeds from 45-65 are more "theoretical", there's pretty much no trip imaginable (that is long enough for range to matter) that would stay in this range.

Thanks Nick-- great graphs.

I attempted to extrapolate the ideal range graph to much higher speeds. No idea how accurate this is, but it looks kind right. Use your own judgement to adjust to real world range:


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Well, I just made the run out to Palm springs for fun. It was 98 deg outside and we had the AC on auto set to 76 the entire time. I left on a max charge with 260 rated. I drove minimum of 70mph. Once in a while I'd suck a draft off some speedy barge like a suburban, or expedition that would be doing about 80, hitting close to 90 a few times as they would eat ground as the traffic opened up. After 70 miles, we got there with a Wh/mi of 304. We went shopping. Interior temps got to 125 so I cooled it via the app, which ate a mile of charge.
We cruised to the giant dinos and laughed about 'fossil fuels'.
Car interior got warm again, but we just hopped in the car and left with the AC going like crazy on auto and headed to Morongo to eat.
Left after eating and temps were still 92 deg.
Drove home with AC on and got home with an overall trip of 150 miles traveled at 296 Wh/mi. Remaining rated charge of 115.
So I managed to cruise faster than most the traffic around me, on a hot day with the AC blowing and still beat the rated range.
When I would get the draft, I'd see less power used at 80, than at 70 pushing air myself.
I really like the Rated number. I never miss that number by much, + or -. Ideal, I have hit once but not driving like normal.

Thanks for the extrapolation, nickjhowe! Very curious how it will work out for me.

@nick and @pebell
I think that extrapolation is too conservative. Since wind resistance is a logarithmic function, the line should start falling rapidly towards the right of the graph. Every 10 miles per hour takes twice the energy to overcome the wind.

Cn;
So, didja enjoy yourself?

Actually it isn't logarithmic - wind resistance increases with the square of the velocity.

And wind resistance only exceeds rolling resistance above 60 mph (due to the very low 0.24 Cd)

So no reason the curve should not continue the trajectory. Should be pretty easy to test - we just need some enterprising soul to find an airfield and measure Wh/m at 100mph and calculate where it is on the curve.

Anyone up for a challenge?

I enjoy driving and pushing the S to new levels. The POI are just a perk.
I took a picture of our S next to one of the huge dinos and labeled it, "Fossil fuel, LOL"
My last 500 miles avg 292Wh/mi which is usually traveling to the in laws up the hill in Ramona. My current last 65 miles are at 279 Wh/mi, cruising to work and back.


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