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Well? What is your average Wh/m?

I drove 204 miles as carefully as I could, and managed 348 Wh/mi to get home with 21 miles of range to spare.

My average over 1200 or so miles is closer to 375, and it isn't uncommon to see 400Wh/mi with "normal" driving.

What are you seeing?

The original thoughts of "300 mile range" seem out of the question here in the midwest.

I've averaged 331 Wh/mi over the first 1500 miles. I occasionally drive 75-80 mph on the freeway, but more often my top speed on any trip is in the 50-65 mph range, and grocery runs top out at 45 mph. I've got a non-Performance model with 19" wheels; full performance starts and sustained high speeds are what push up Wh/mi the most.

85000Wh/331Wh/mi = 256miles. Still quite high if you compare it to reviews.

If I understand correctly, 265 miles is based on 308Wh/mile. 265*308=~81,6kWh. The rest is supposedly kept as a reserve.

This would make his range 246 miles.

I have only driven 500 miles and so far am at an even 300wh/mile. It dropped to that level from 304 wh/mile after a 90 mile mostly highway drive at 60mph. I do tend to drive conservatively.

Elon said at one point something like this "lets see who gets 400 miles on one charge first".

85000Wh/400miles = 212.5Wh/mile. That's roughly 2/3 of that 308Wh/mile.

Which speed gives you approx that number? Is it close to that in city traffic? Blog chart puts 400 mile range at roughly 37mph, is that even close to real life figure?

So I have 1,644 miles and my average since day 1 is 344Wh/mile.
However just a few weeks ago I was averaging 331. My driving habits haven't really changed; however, 2 things have changed. First I switched from the 21" performance wheels and tires to the 19" wheels and snows. Also, being in NJ the weather has been much colder the last few weeks (down around 32 degrees at night. With the cold the car apparently does not coast regen the battery until the battery pack warms up. For instance last night it took a good 15 minutes to be able to regen fully when coasting. There is a dashed yellow line that appears in the regen area of the speedometer display. This is also probably negatively impacting the Wh/mile rate.

Most of my driving has been back roads but I live in a hilly area and that results in not being able to achieve a rate similar to some of those above. I drive about 20% highway and 80% back roads. I will be taking my first long trip this week from NJ to CT to Boston to NH to Mid Mass to CT to NJ which is about a total distance of 500 miles. I am going to reset the trip odometer and see what my rating is based on mostly highway mileage probably at an average speed of around 70 MPH. Might also see how it handles in the snow as we are expecting a snow event in the Northeast this Tues/Wed.

Did a 255 mile trip yesterday and averaged 295 Wh/mile. That was on a single charge. Had 10 miles left when I got home. Average for 2500 miles is 310Wh/mile. BTW, my trip had 4 adult aboard.

Can everyone post which version s they have, ie performance or not?

After 3,700 miles our average is 318 Wh/Mile in our 85kWh non-performance Signature Model S.

jkirkebo is right, the usable battery capacity is less than 85kWh. Based on empirical data I’m collecting in our Model S, and assuming a normal distribution, the usable battery capacity is between 80.8 and 81.7 kWh (99% confidence level). As an aside, this puts the Rated Mile efficiency between 305 and 308 Wh/Mile.

perf, 377Wh/mi

1700 miles, sig performance, about 352 wh/m, there was the 1021 mile road trip, the rest are maybe half lcal half highway. I don't drive particularly slowly.

I don't doubt that temperature has some impact on the matter... It does get cold in Wisconsin. (not to mention it isn't exactly flat)

Mine is Signature Performance.

In general, I drive it like I would drive any other car. I use the climate control to stay comfortable, I turn on the windshield defroster when necessary to maintain the ability to actually see the road. You know.... the little things.

Thoughts of 300 miles or more seem less like driving and more like theoretical driving conditions and ridiculously slow accelerations, only driving with the wind, tailgating 10ft behind a semi trailer.

For me, Chicago is 100 miles away. I've made the round trip, but it wasn't comfortable - was not able to "keep up with traffic" without giving up on being confident that I'd make it home.

On my commute (Silicon Valley traffic), I get 289 Wh/m. For high speed trips it is more like 340.

355 Wh/mile over the fist ~400 miles. Used for Silicon Valley 280 commute, e.g. periodic burst to 85mph and long sustained stretches 70-80mph up and down hills some city streets and the occasional stop and go back up

Sig performance, 1800 miles, getting consistent 350Wh/mile. Earlier, I was getting 335Wh/m, but I've started driving more "spiritedly" lately. As of today, I've had my Model S for exactly 1 month!

@Vic M;
Very glad to see you say that!

Cross-posted:
... when EPA came out with the ratings saying city driving got lower MPGe than highway, I was very dubious. Didn't fit the BEV profile at all, or the early beta reports.
.
But late in the game, it seems Elon ordained a retuning to give more oomph in the passing ranges. It now occurs to me that since you don't get something for nothing, that this moved the power band "north" at the expense of low RPM efficiency. Don't know how this was achieved, though.

Interesting comparison: I just stumbled across a comment from an i-MiEV driver who bragged that he achieves 255 Wh/mi (real-world driving averaged over all seasons incl. heating and accessories). Given the size, weight and power of an i-MiEV, it occurs to me that the Model S' power consumption compares favorably.

In all fairness, it should be noted that the above mentioned 255 Wh/mi for the i-MiEV (real-world driving averaged over all seasons incl. heating and accessories) was measured from the grid, not from the battery, i.e., while all numbers for the Model S that are mentioned in this thread ignore charging losses, the i-MiEV mileage includes them.

It's the weight of the Model S which makes it use more than i-MiEV. You just can't beat rolling resistance difference by better engineering if other car weights only half of your car.

Also frontal area is quite a bit bigger (i-MiEV is only ~1500mm wide while Model S is more than 2000mm, about same height).

Considering those Model S is very efficient vehicle, though I still wonder why does it weight so much.

8000 * 46g (about 90kWh) is only 368kg and car weights over 2100. That's a lot when almost entire car has been made using aluminum. Is it the wiring? Does the liquid cooling add hundreds of kg? Motor is tiny, but it probably still is (with PEM) 100-150kg. Battery pack casing? Bottom armor protecting the batteries? All of the above?

I have created the following google doc/form for entry of date to get some Avg numbers

https://docs.google.com/spreadsheet/viewform?formkey=dHc3Y2JwSmlpMWdFY2F...

I only have total avg calculated at this point but intend to add per type of car avg.

The raw data can be seen here and the avg calc in the I & J columns

https://docs.google.com/spreadsheet/ccc?key=0AhXq4QSAykf4dHc3Y2JwSmlpMWd...

My Leaf is at 286Wh/mile so far this year, measured from the battery. I often do not drive very economically as we have a lot of quick chargers around now. I'd rather use heat and travel at a good speed and use 10 minutes for free QC, than travel slowly while freezing ;)

A bit off topic, but for those with experience, if the reserve power indicates 10 miles, how accurate is this value? I would expect it will depend on driving style for the balance of the power, but thought I'd ask what some are experiencing. Thanks

I think I'm driving her too hard. I'm at about 400 Wh/ mi, after 2 weeks. I can't resist!! I only drive about 40 miles a day, so I don't care.

re: Velo1's question;

Suggestion: when the projected miles is very low, reset the system to the lowest averaging base value, and watch as you drive. That should show the effects of "careful driving" best for that last leg.

Thanks H.

Andrew;
Hey, when you've got a rocket in your pocket ... ;0 ;) ;P

Andrew;
I can just hear you: "Ohboyohboyoboy! Commute time again!"

@ Velo1 – When the Rated Miles Remaining indicates 10 miles, you will be able to drive 10 more miles if you drive at 307 Wh/Mile. You will drive more or less than 10 miles if your energy use is better or worse than 307 Wh/Mile. You can monitor your current energy use on the Energy app on the 17” touch screen. When the Rated Miles Remaining reaches 0, the car stops, there is no reserve capability.

@ Brian H – What does “reset the system to the lowest averaging base value, and watch as you drive” mean? I’m not sure you can do what you are referring to in the Model S.

You have "projected" options, don't you? Averaging over 30 miles, or less? Pick the lowest figure, that will give the best instantaneous read on how far you have left if you carry on as you've just been doing. Eg, show the effect of slowing down.

@ Brian H - There are only two range predictions in the Model S - Rated Miles Remaining and Projected Miles Remaining. Rated Miles Remaining is based on a constant power usage derived from the EPA 5-cycle test. Although Tesla does not advertise this value, based on empirical data I collected I determined that is about 307 Wh/Mile. Projected Miles Remaining is based on the Wh/Mile experienced over the last 30 miles and is constantly updating as you drive. You cannot select a different mile range or a different efficiency to be used in the Projected Miles calculation. In addition to monitoring the Energy app display, you can also reset one of the two trip odometers. The trip odometers display miles traveled, kWhr expended, and power usage in Wh/Mile since the last reset. So with 10 Rated Miles Remaining, you could reset a trip odometer and then monitor the Wh/Mile as you drive. If it is more than 307 you will be able to drive less than 10 miles and if it is less than 307 you will be able to drive more than 10 miles.