Forums

Range Estimation

Range Estimation

(Sorry if this is covered somewhere, but there is no search function and I couldn't find anything related.)
I did a road trip from Mesa AZ to Payson, a distance of 75 miles, and I started with 273 miles indicated for my charge level. I did have the A/C on, and drove the way I drive - fast (80 mph for much of the drive). There is also a 3600 ft elevation gain. When I reached Payson I only had 120 miles showing on my charge level instead of the 200 miles or so one would naively expect - 80 miles less. In other words 75 miles of fast, hard, uphill driving required double the distance in charge. (Going back, of course, I did much better as I was charging the battery going downhill.)

I'm not terribly surprised, and I haven't yet done any long range road trips, but this concerns me as I'd like to have a better feeling about my range capability when I start.

Some time ago, I know Tesla had an interactive program that would allow one to put in all sorts of factors - temperature, a/c on or off, starting location, destination, driving speed, etc., and it would give an estimate of charge level needed. Does that still exist somewhere?

I thought Tesla would have implemented an adaptive range estimate based on recent driving history, driving route, time-of-day, etc.

I'd appreciate some advice as to how to get a better range estimate.

CharleyBC | 14 maj 2019

The miles of range indicator is kinda dumb, and I don’t mean that in a pejorative way. It doesn’t know where you’re going or how hard you plan to drive.

You largely answered your own question. You were going fast, uphill. Drag is a function of the SQUARE of velocity. And climbing is climbing. AC is a bit of a factor, but not so much as heat would have been.

Check out abetterrouteplanner.com. It does a decent job of factoring in variables.

CharleyBC | 14 maj 2019

Newtonian physics geek extra credit: how much energy is required to lift a two-ton object 3600 feet in Earth gravity? Express your answer in kWh.

EVRider | 14 maj 2019

Another option is https://www.evtripplanner.com. Tesla has an online route planner, but it doesn’t let you enter variables, so you were probably thinking of one of the third-party sites, which do.

Bighorn | 14 maj 2019

If you’d put your destination in the nav, you’d have had an accounting of the elevation gain. Your markedly faster speed than EPA testing would be factored into your arrival SOC after a few dozen miles. You lose about 8 miles per 1000 foot net gain.

Magic 8 Ball | 14 maj 2019

@Charley That would depend on the losses associated with work required to do the lifting.

edhchoe | 14 maj 2019

Use Navigation even if you know the way.
Then you get the consumption graph.
As you drive, the graph shows ideal vs current.
Yes, driving at 75 mph vs 80mph results in a huge difference in consumption.

dgaz | 15 maj 2019

Thanks for all the feedback. As I noted, I wasn't too surprised at the data but wished to know what else is out there to make a better estimate of range. I will check out all of the suggestions.

jimglas | 15 maj 2019

I have found to navigation in the car to be remarkably accurate in estimating energy use

M3BlueGeorgia | 15 maj 2019

@dgaz: Agree with @jimglas

Use the onboard navigator as that adjusts for your recent driving style and provides a usable accurate estimate of arrival charge.

Always remember the battery amount shown next to the speedometer is based on EPA miles, which wouldn't be applicable for your scenario. I've changed mine to display percentage.

kcheng | 15 maj 2019

Try abetterrouteplanner.com

don.lind | 15 maj 2019

Also, there's that built-in "energy" application.

It shows a graph of your energy consumption for the last 5, 15, and 30 miles of driving.
It shows the Watts per Mile and an estimated remaining range that you'd get if the energy use remained the same as it has been for the last 5, 15, or 30 miles.
See: https://www.youtube.com/watch?v=8s773I_XPlM

I've always had the main battery graph showing miles of range but I know it's not a perfect estimation.
That's apparently calculated purely using the standard 241 watts per mile energy consumption and the percent of battery left. That is, the range it displays assumes you're burning 241 watts per mile of driving.
That's an OKish estimate.
But if you drive up a mountain, drive 80 MPH, drive in the rain, use the heater or AC, you'll likely be burning a lot more than 241 watts per mile.

With the energy graph thing, you have the ability to see other live, on-the-fly estimates of remaining range.
But, generally everything won't stay the same for a long time. You'll get to the top of the hill (and maybe drive down the other side). Weather may warm up and you can turn off the heater. You slow down to 65 MPH...

But yeah, some of those websites mentioned above can take tons of this kind of stuff into consideration.
I've played with abetterrouteplanner.com...