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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.

First I'm in Ohio and heat is required.

Delivered Nov. 2nd - 1511 Miles - 548.5 kWh - Average - 363 Wh/mi

This would be much lower, but I've given at least 12 test rides with full acceleration to prove that an electric was not slow. Once those rides are over and the newness goes away, I image I'll average about 320 during the colder months and less during the summer.

bottom of p17 of the Owners' Guide:

To display how much energy Model S has been using, touch the Energy
APP on the touchscreen. This displays a graph that you can pinch or
expand to display the energy used over the past 5,15 or 30 miles. This is a useful way to show how driving habits and condition impact the amount of energy use"

I learned this from cinergy's videos!!


I've been driving in Seattle, in the dark (mornings and evenings), with lights on, heaters on (35-50 degrees outside), in a mix of rush hour traffic and highway speeds, in a hilly envoronment. I'm seeing around 425 WH/mi average over the first few hundred miles (and pretty consistent on a daily basis), or roughly 170 miles on a standard charge. I hope due to the above, that in summer (or on the highway) I will see a higher range.

For the EPA estimate: with 85kWH and 265 miles EPA, that is 320.75 WH/mi (e.g. ~320); it's straight division. For the "standard" charge, I see a rated 238-240 miles fully charged - which is almost exactly 90% of 85KWH at 320. (240/265 is also 90%). The "standard" charge cycle is therefore 90% of the full change.

@ Brian H – I am very familiar with both the Guide For Owners and the Energy app on the touch screen. In your second to last post you said, “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.” The Energy app screen you reference in your last post does not provide an “instantaneous read of how far you have left.” The Energy app screen can be set to display the last 30, 15 or 5 miles. The screen displays the instantaneous power use in Wh/Mile, the average power use in Wh/Mile over the selected miles (30, 15 or 5) and a graphic representation of the power use over the selected miles. To use this screen to obtain an “instantaneous read of how far you have left” one would have to make the following calculation: (Rated Miles Reamining) x (307) /(average Wh/Mile from Energy screen) = miles remaining if driving efficiency does not change from the average displayed on the Energy screen. I find my previous recommendations more useful for determining how things are progressing near the end of a battery charge.

@ John-S886 – You are correct that determining the power use of a Rated Mile involves straight division once you know the usable battery capacity and the 5-cycle EPA mile value. Fortunately, the 5-cycle EPA value is an official, published number, 265 miles. However, the usable battery capacity is not published anywhere and it is definitely less than 85 kWh. I have collected extensive data while driving over 3,900 miles in my Model S. Based on my data, the usable battery capacity is about 81.3 kWh (assuming a normal distribution, it is 81.3 kWh + or – 0.4 kWh with a 99% confidence level). Now the straight division will yield the correct value for the power use of a Rated Mile, about 307 Wh/Mile.

With respect to your calculation of a standard level charge there is another issue at play. When the Rated Miles Remaining (RMR) reaches 0, there is still 5% to 7% State of Charge (SOC) left in the battery. I have driven my car to this point on two occasions. What this means is that you cannot divide RMR by 265 to determine the battery SOC. The battery graphic displayed on the Charge screen on the touch screen is a very good estimate of the SOC of the battery. Tesla has informed me that the standard level charge changed from 85% to 87% SOC with software version 1.9.17 which was released on 9/26/12. Apparently this 87% value isn’t a hard number since I routinely see 93% SOC on my car following a standard level charge with the RMR of about 240 to 244 miles.

It looks like real world conditions can possibly knock the actual range to 50-70% of the advertised numbers, and it's not even winter yet. This is a great thread because purchase decisions are being made on the advertised ranges and the real world data is indeed "eye opening".

I finalized with a 60 kWh battery to get the sub-six second 0-60 time, but now I realize I need it for the range also. Those considering a 40 kWh battery are going to get less than 100 miles if they live in a hilly area and have real winter weather. Choose wisely!

If you take an ICE car, would you normally drive with less than 30 mi range left ?
It's as hard (if not harder) to predict how long that would last since different manufacturers have different ideas about fuel tank size and reserve.
85kWh battery is definitely worth the expense so you don't have to wait for your range to drop to 10 mi and then guess whether you make it or not.
It's probably good for science but is unnecessary in most cases.
If I know I'm averaging 378Wh/mi, I wouldn't drive over 200 mi between charges and realistically I wouldn't let it drop under 30 miles, so probably 170-180 miles tops.
It's a bit harder than ICE cars at the moment since in populated areas you're almost always within 30 mi range from a gas station and not necessarily within same range from a charging station.
We'll get there with EVs in a couple of years, thanks to Tesla that made a real and desirable electric car justifying an investment in charging infrastructure.

@Rod and Barbara, can you program display to show you what your average power usage should be to reach some point into GPS map at your current speed? AFAIK you get your current power usage in dash. Am I correct in that?

If there is no such display I think that would be nice to get into Model S power display options. Not just your Wh/mi but W at your current speed. Kind of "don't go above that line, and you will be fine".

Rod, you can, however, choose a last 15 miles or 5 miles energy use chart on either the touch screen or the dash. Not sure this helps a lot.

Brian and others: I'm doing almost all city driving in SF, up and down, up and down, and I'm over 400 in that venue. Out on the road is much better.

Seems to me that 307 is a very difficult goal to attain, so we all ought to be cautious at the end of rated miles.


@ Timo - The display of needed power usage to reach a location does not exist in the Model S. There are multiple displays available to monitor current power usage or the average power usage over the last 30, 15 or 5 miles.

Indeed, "instantaneous" is a bit strong. The 5 mile average would give a more responsive indication of how you are doing squeezing out the last few miles, tho'. Imagine the opposite situation, if you only had projected range based on, say, the last 1000 miles; that wouldn't tell you much about how likely you were to make it home when you're hyper-crawling along!

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