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Creep Impact on Range

Creep Impact on Range

Do any of you have any empirical data on how (or if) range is affected by the new creep feature?

jbunn | November 12, 2012

If you're using creep to hold your position on a hill, you're using power. Better to use the brake.

Level ground, creep should be no different than driving really, really, really slow.

DouglasR | November 12, 2012

I know it would take a really really long time to go 265 miles.

Brian H | November 13, 2012

DouglasR;
That's a truly creepy image ...

>;(
:p

richb28 | November 13, 2012

I have definitely noticed a difference in wh/mile ratings since I installed creep. Noting empirical just anecdotal.

nickjhowe | November 13, 2012

It is a pity this graph doesn't go below 10mph:

Since rolling resistance is independent of speed, and drag effects are negligible at low speed it suggests that the motor efficiencies are much lower at lower speed. Creep is therefore one of the least efficient places to be.

Without creep, it is likely that at 0mph there is zero current going to the motor (given the "rolling backwards on a hill" statements). With creep, and with sloppy programming it is possible current is always being fed to the motor even when you have the brake on, and therefore you are using power to stay still.

Wild speculation on my part...

Timo | November 14, 2012

Chart real start point is zero range at 0mph. Going very slowly rolling resistance and all speed-independent ancillary losses have enormous impact on range.

OTOH it does not mean that you lose a lot of charge / second, just that you didn't move much. It's like wondering what is your range when your car is parked, you have zero range because any loss of charge is enough to drain the battery eventually. Creep doesn't have huge impact on range unless you try to actually get somewhere using it.

STEVEZ | November 14, 2012

Unlike with automatic transmission in an ICE car, the Model S creep function applies no torque and uses no power when the car is at a complete stop. As others have said, it shouldn't impact range much unless you try to go somewhere using creep. Or, just possibly, if you creep at every traffic light instead of coming to a complete stop.

I keep vacillating about whether to leave creep on; it's turned off at the moment.

STEVEZ | November 14, 2012

Pondering the graph posted above: is the fact that the S gets its best range at a higher speed than the Roadster due entirely to superior aerodynamics?

Timo | November 14, 2012

Actually combination of higher rolling resistance and about same CdA. If you drive a very heavy car the sweet spot of the range is higher because it moves the speed where air drag starts to affect more than rolling resistance.

Difference would be much more clear of Roadster would have same Cd as Model S, unfortunately it is more like a smooth brick for aerodynamics point of view.

Heartland | November 14, 2012

@Stevez, I seriously doubt that creep uses no power when the car is at a complete stop. Maybe you misspoke and mean if you have the brake on in which case you really are not "creeping". In the Roadster when I have my foot off the brake I can see it does use a small amount of power to creep. When I have my foot on the brake it does not use power and there is no creep. I would expect the same results using the Model S.