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How to Squeeze the Most Miles out of a Nearly Dead Battery?

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My car is in a parking lot with 25 miles of range and no charger. Nearest supercharger is 38 miles away. Is it possible to drive in such a way as to squeeze 38 miles out of a battery with 25 indicated?
did you check plugshare for any closer chargers? is there a 110 outlet available nearby? this will be dreadfully slow but in about 6 hours you'll have enough to make it to the SpC.
 
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Anyhew,
Range mode on (energy saving on 8.0), A/C off 25-35mph, light acceleration, max use of regen as opposed to brakes.
Turn on energy graph set instantaneous 5 miles start your drive and it will tell you immediately what your actual real time range is and you'll know,if your gonna make it.

In between find a 110 plug if your not gonna make it.

Best of luck!
 
did you check plugshare for any closer chargers? is there a 110 outlet available nearby? this will be dreadfully slow but in about 6 hours you'll have enough to make it to the SpC.

That's a good resource, thanks. I'm in an airport parking lot with EV chargers, but they're all full with cars that will be there for days. Plugshare says there's charging in the free waiting area so I'll check that out.

25 rated or ideal?

Not sure. Just says 25 on the instrument cluster.

Anyhew,
Range mode on (energy saving on 8.0), A/C off 25-35mph, light acceleration, max use of regen as opposed to brakes.
Turn on energy graph set instantaneous 5 miles start your drive and it will tell you immediately what your actual real time range is and you'll know,if your gonna make it.

In between find a 110 plug if your not gonna make it.

Best of luck!

Good to know. The other drivers on the freeway will curse at me but it's better than nothing. Is there any power in reserve once the indicator reads zero?
 
Is it downhill to the supercharger?

If not and you have AAA try calling for a mobile charge unit, someone had posted a pic of one on a recent post.
If you're going to call AAA anyway, why not try and make it first and then call if you can't? An S85 can go close to 500 miles at 25MPH so, if you go slow, you might make it.
 
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In the Roadster, at least, peak efficiency was at 18mph, so yeah slower is generally better if you can. Increasing tire pressure is a great idea. If it's warm, flat or downhill, dry and no wind you should be able to make it at that speed, but boy I would hate to try. I agree that plugging in to 120V somewhere to get a bigger buffer is a good idea. Driving steady is better than stopping and starting if you can; but if you do have to slow down, as noted above regen is better than brakes.

By the way, while some people get lucky and have driven past zero miles, Tesla does not keep a buffer of energy below zero. Tesla has been extremely clear from the very beginning that zero means zero, and many cars have shut down at zero - in fact a small handful have shut down before then (though not much before - maybe 2 to 4 miles - and they were generally going at fairly high speed). Of course, the battery doesn't store miles, so Tesla just has to estimate when the battery will reach conditions that cause it to shut down. It is a conservative estimate to help ensure shutdowns before zero are rare, so sometimes you may get lucky with a too-conservative guess and be able to go beyond zero. I have heard of people getting as far as 17 miles past zero. But you absolutely can not count on that. It's just a sometimes-side effect of a conservative guess. Going really slow in good weather conditions will increase your chances, but guessing at the bottom of the battery is a very delicate business.
 
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Good to know. The other drivers on the freeway will curse at me but it's better than nothing. Is there any power in reserve once the indicator reads zero?

Not to overstate the obvious, but please never drive on a freeway at 35 mph.
At best you (only) get ticketed, at worst you may cause or be involved in a traffic accident.
Bad Karma.
Best to use the side streets if that is your stated mph goal.

Most cities that have an airport with chargers also have something nearby on plugshare, even a residence.
Yes, Superchargers are always fastest charging, but the best driving tactic is one that allows you to arrive with some amount of charge still in your battery pack.

Have your A/C turned off, windows down.
And Zero does mean Zero.
If you get below Zero and are still driving, there is a lucky angel following you around.
I do know a local driver whose car did shut off with couple of miles still indicating on his battery charge.
And it was not during cold weather.
 
I think if you drive right about 35mph you'll get great range... Assuming the roads aren't all surface streets anyways.

Anyhew,
Range mode on (energy saving on 8.0), A/C off 25-35mph, light acceleration, max use of regen as opposed to brakes.
Turn on energy graph set instantaneous 5 miles start your drive and it will tell you immediately what your actual real time range is and you'll know,if your gonna make it. In between find a 110 plug if your not gonna make it.

Best of luck!

Maximum range has been achieved at 25 MPH based on testing with AC and accessories off :cool:

Model S Range.jpg
 
Oh yeah, thanks for pulling that up, I forgot I did that chart for the Model S in addition to the Roadster. That was from THIS thread.

The green line at the top was data from Tesla assuming ideal conditions (flat, warm, no wind, etc); the green shaded area was my calculation for HVAC draw (based on numbers from Cinergi, if I recall).
 
For those wondering I was able to grab a slow speed charger at the airport to get enough juice to get to the supercharger. Glad I did, as driving slow with the AC seems to get you about 20% better miles than the indicated range, so there's no way I would have made it otherwise.

Now at the supercharger in a line 4 deep waiting for a space to open up. The joys of being a new tesla owner i suppose.