Range mode

Range mode

With the X out for a year or so now...feelings on Range Mode? Does it make much of a difference to you? With our P90D we kept it on most of the time but our mileage was awful anyway so I'm not sure it made a difference. With our 100D I'm once again starting to consider trying to get reasonable range.

So do you even bother with Range Mode?

brad | 28 juni 2017

Range mode definitely helps, but the single most important range tips are:
a) Turn off air conditioning. It really chews power. You can have it off and adjust fan speeds, air flow, etc which is usually all that you need.
b) Driving speed: Every extra MPH chews more energy. It's the square of the difference. So 70 v.s. 75 is 25w extra power. Slow down to get more range and save time because charging for less. The Tesla is a beautiful driving experience, a bit slower to enjoy it more can make the journey faster anyway in saved time.
c) Use range mode. But it's unclear whether to turn range mode off when Supercharging.
d) Use autopilot. Or at the very least, cruise control. It's far more precise than any human input so keeps the usage closer to the 0 mark. Having a consistently lower energy usage gives longer range than sharp starts and stops. Even though there's regenerative braking, a lot of power is lost through the surges of power to/from the battery in the form of heating, chemical reactions, traction on the road, etc. Even if you think that you are driving steadily, your foot is moving all the time. The car's automatic speed control is way more precise and adds miles to your range.

These 4 things are the single biggest factors to getting great range. Another great tip is to not waste time charging to full. If you're on a long trip, two stops to supercharge at 90kw or more is much better than 1 stop that charges more fully but goes all the way down to the slower <90kw charging speeds.

Triggerplz | 28 juni 2017

I don't have range mode on as I like those cute lights on the front to be on with range mode they are off

Redmiata98 | 28 juni 2017

brad why do you state this "But it's unclear whether to turn range mode off when Supercharging."
Range Mode is for duscharge of power, are you aware of a difference in charging time with it on?

Vawlkus | 29 juni 2017

It used to be the supercharging while in range mode would result in a slower rate of charge. I don't know if this is still the case or not.

psusi | 29 juni 2017

While it is true that wind resistance increases exponentially, your 25w figure is totally pulled from thin air. The actual figure is much, much higher than that.

Rocky_H | 29 juni 2017

@psusi, +1 And this other part is something I learned just recently. It's the wind resistance force on the car that goes with the square of the speed. But the power needed from the car to overcome it, goes with the _cube_ of the speed. So yeah, the battery drain goes up a lot faster with speed increases.

rossRallen | 29 juni 2017

Yes, drive power goes as the cube of the velocity.
Drag force increases with the square of velocity,
Power = velocity * drag force ~ velocity^3
There are other effects related to speed, but this is the dominant.

I have never noticed a range difference with Range Mode. I also like having the driving lights on to make my X even more visible to others. There's a cool factor as well.

RT_UK | 30 juni 2017

Interesting, didn't realise that the Daytime Running Lights are turned off when Range Mode is on - how much tangible energy consumption can be saved by turning off two LED strips?!

psusi | 30 juni 2017

I think you're misinterpreting what you are saying. The instantaneous power required does go up with the cube of velocity, but you don't care about that. What you care about is the energy efficiency, or how many Wh per mile, and that is still just squared.

Rocky_H | 30 juni 2017

@psusi, That's not how math works.

You're using that instantaneous power, measured in kilowatts, to overcome that wind resistance. As you use that extra level of power for 1 hour, 2 hours, etc. you multiply that. So you have kilowatts times hours, which is kilowatt hours. That is the amount of extra energy you have used to overcome the extra wind.

Solarman004 | 30 juni 2017

I find Range Mode to be very valuable on cold winter days when I'm taking short trips. It greatly reduces the use of the battery heater, and improves short trip efficiency. I keep it on until the regen-limiter dashed lines disappear indicating the battery is warm.

psusi | 3 juli 2017

@Rocky_H, no it *is* how math works. You are using more watts, but also getting more miles per unit time. That is, the power at twice the speed may be 4x as much, but you are getting twice the miles per hour, so the power consumed per mile is only 2x as much.

speyerj | 3 juli 2017

I don't think all the physics majors on the internet are wrong about the nature of power required to overcome resistance.

You are correct, you go faster, so you spend power for a shorter amount of time, but the time saved is not enough to offset the increased energy expenditure.

A theoretical car that has a 4 sq foot frontal area travelling 40 mph burns 1.7 HP to overcome wind resistance. The same car at 60 mph burns 5.76 HP to overcome wind resistance. The first case takes 3 hours to go 120 miles, the 2nd takes 2. You can readily see that the time saved in case 2 is not enough to outweigh the increased horsepower. Time savings is 33%, whereas the horsepower requirement has gone up by 338%, even accounting for the shorter trip you're burning almost twice as much energy to overcome wind resistance.

foryatin | 12 december 2019

I have a model x performance and its using 630wh/m, does anyone know what the problem could be I drive mostly in city on chill mode no hard acceleration or anything like that but my battery is getting drained pretty fast the temp here has been cold close to 30 deg but I am only getting 50 % of the driving miles per full charge.

Bighorn | 12 december 2019

630 sounds like something you’d see for the first few miles when the battery is cold and both cabin and battery heaters were running. That should normalize when the battery came to temperature. And getting half the miles on a full charge would be very rare on a single trip, but not so if it were a bunch of trips.

pctooling | 2 februar 2020

If yours Tesla was made in early 2016 or before 2016 Tesla Capp maxim charge from 90Kw to approx. 75Kw and slow dawn charging to prevent battery fire .Battery 65Kw,75Kw, 85kw ,90kw. Tesla confirm the are down braiding vehicles without permission.Good luck