Model X: Average Wh/mile Tracker

[ajdelange]

I find this suggestion rather amusing.

It was, of course, intended to be amusing. For the not so literal minded it means that you are likely to experience lower energy consumption per mile on longer trips as my trip history, which represents a small sample size for sure, clearly indicates. My trip history also indicates the the TREND is for longer trips to register better mileage but that this is only a trend. There is still plenty of variation possible on small trips.

I am reposting the curve from earlier with the 95% confidence band. Readers conversant with the methods of statistics will understand what this says. For others: the interpretation that longer trips give you better Whr/mi numbers is validated (with 95% confidence) even though the data sample is small.

This got posted before I was finished. I will continue with other comments in another post.

 

[ajdelange]

It actually reminds me of an argument I once witnessed in another forum where someone insisted that the MPG estimator in their vehicle was wrong if they reset it when they filled the tank instead of after they were up to speed on the highway.

And he was absolutely right were he interested in highway MPG.[/QUOTE]

I don't know whether they refused to believe that starting the engine and accelerating from 0 used more fuel (energy) than maintaining speed on the highway

The per mile consumption is certainly higher during acceleration with an Otto engine or an EV.

...or refused to understand that the high consumption showing would be brief because it had no previous data to average out against, but it was impossible to convince this person that the MPG estimator was actually accurate for the full tank if reset when refilling.

That depends on what the person is interested in. An average is computed over a span of data. Different spans give different averages. That's why the consumption graphs displayed by the car are bumpy. The individual points represent averages over a half mile in the 5 mile plot and probably a mile or two in the 15 and 30 mile plots. The departure tax is displayed as high value points early in the trip. As the departure tax "averages down" after some miles the display begins to be more centered about the mean.

Back on the topic of your post being over-simplified and/or off-point,

The curve is a simple representation of what others may experience and it's certainly not off point because folks here are interested in knowinhg what kind of energy consumption to expect. The post explains the departure tax and talks a little about how it appears and why.

But let's see what other areas you need a little help with.

here are the biggest problems I have with this analysis:

• You don't ALAWYS use heat or even A/C, so while these numbers can be involved in "departure tax" they won't always be.

• No, of course not and when the departure tax is small you don't see as much effect from it. That's why some of my short trips show consumption of less than 350 and even, for 2, less than 300. This illustrates the value of doing whatever you can to lower the departure tax as I suggested in the original post.
• 
  

  Heat, A/C, and other accessories use Wh/h, not Wh/mi, so more miles isn't automatically going to lead to a better rating, because sitting in traffic is still using those Wh/h and averaging them back into the counted miles.

  This was specifically covered in the example of 60 mpH and 1800 Watts. I assumed readers would be able to extend this to other speeds and power draws. Whr/mi = watts/mph. Thus, ostensibly, the faster you go the less the heater costs you per mile. But note that your traction demand will go up as the square (actually 2.5th power per ABRP's data) of your speed and at higher speed you may get more infiltration and thus the heater may run more.
  

• To said second point above, you seem to be acting like BEV is different than an ICEV, when in realty, they aren't.

  No - not at all. They are indeed similar. There is a departure tax for an ICE vehicle just as there is in the Tesla. If you sit in your Lexus for half an hour with the heat and radio blasting you will use fuel even though you have not moved an inch. The mpg number averaged over the first couple of tenths of a mile will be worse than once the tax is averaged down some. The big difference, of course, is that in the Lexus the heat is waste heat and the departure tax is only the idling fuel used to run the engine while you are warming up the car. In the Tesla the heat comes directly from the "fuel" supply and thus has a more profound effect on range.
  
• 
  

  While some of what you are classifying as "departure tax" is more prevalent at the beginning of a trip, most of it is not.

  No. I think you are missing the point that the departure tax is paid before you depart - just as is the case with an airport departure tax (which I always thought showed that the Aussies must not think very much of themselves if you have to pay to get out of of their country).

• The fact of the matter is that accelerating takes a lot of energy (and the amount of energy required for a given acceleration increases at a higher rate than the speed of said acceleration).

  Acceleration does not take place until after you depart. F = m*a. In t seconds the car moves x = a*t*t/2. The energy used is E = F*x so that clearly the energy use per unit of distance is just m*a. This is, for uniform acceleration, independent of speed. Now E = Fx = m*a*a*t*t/2 and the time derivative of this, P = m*a*a*t i.e. the power required for constant acceleration is a function of the square of that acceleration and the duration of the acceleration. For constant P the acceleration will be sqrt(P/(m*t)).
  

• To illustrate this point and tie the story from my previous paragraph into the topic, if you were to stop halfway through a drive and actually turn your Tesla off and back on (to Car Off state and then back into "PRNDS" state to reset the figures, not recommended, potentially unsafe [although it may be able to do something similar with the trip meters]), you would find out that the initial Wh/mi would still be bad from that acceleration even though the "start of trip" factors were already leveled off.

  Any time you put a big demand on the battery, be it departure tax, acceleration, going up hill, accelerating while going up hill... that big bump in the power graph starts its way along the sliding window of whatever integrator you are looking at. You will see a bump in the energy display that moves off to the left of it just as the departure tax moves off to the left of the display. If you stop the car mid trip and then start up again with booming acceleration then for this trip the departure tax is small but the acceleration bump goes into the first couple of cells in the integrator window and looks just like the departure tax.

The fact of the matter is that the sample set is simply too small at the start of the trip. Having this meter just for the current trip is no different than resetting an MPG estimate at the beginning of every trip, but it is apparently information overload for some people.

Your comments above suggest that you don't fully understand what is going on here. I hope my responses will help you to. Once you learn how to interpret the meters and graph they will be seen to be a font of information - at least to a geeky guy like me.

If still experiencing "departure tax syndrome" after taking said action, I also recommend they move away from flat areas so that the hills make it disappear.

Hills won't make the departure tax disappear. They will simply put more bumps that look like the departure tax on the display with the difference that the departure tax represents an "impulse" as it is billed to the first tenth of a mile (the apparent sampling interval of the car) whereas the hill will appear in bins corresponding to the actual length of the hill (could be a tenth of a mile, I guess).

 

[mxnym]

So as to not get into an extended argument with you, I will acknowledge that we are talking past each other and only respond to a couple points that have anything to do with what I was saying.

And he was absolutely right were he interested in highway MPG.

He was interested in his "actual" mileage and believed it was wrong if he reset it at fill-up instead of in the highway. He only reset it on the highway after filling, not for each trip or anything like that.

• No - not at all. They are indeed similar. There is a departure tax for an ICE vehicle just as there is in the Tesla. If you sit in your Lexus for half an hour with the heat and radio blasting you will use fuel even though you have not moved an inch. The mpg number averaged over the first couple of tenths of a mile will be worse than once the tax is averaged down some. The big difference, of course, is that in the Lexus the heat is waste heat and the departure tax is only the idling fuel used to run the engine while you are warming up the car. In the Tesla the heat comes directly from the "fuel" supply and thus has a more profound effect on range.

The Lexus most likely only shows an average MPG, and only from the time you last reset it. As such, assuming you reset when you fill up (because otherwise you probably never reset or only reset before long trips), the big departure tax you are referring to would rarely be obvious unless you lived right next to the gas station and went home after filling up or you wanted it to and intentionally reset the average meter before causing the departure tax (or happened to actually take these actions just after filling up and resetting at a gas station).

• Acceleration does not take place until after you depart. F = m*a. In t seconds the car moves x = a*t*t/2. The energy used is E = F*x so that clearly the energy use per unit of distance is just m*a. This is, for uniform acceleration, independent of speed. Now E = Fx = m*a*a*t*t/2 and the time derivative of this, P = m*a*a*t i.e. the power required for constant acceleration is a function of the square of that acceleration and the duration of the acceleration. For constant P the acceleration will be sqrt(P/(m*t)).

The problem with this theory is that, at least in my experience, the Wh/mi doesn't populate until you've driven at least .1 miles. In other words, you 've already departed and the cost of some acceleration (which is far more significant than what you were trying to measure) is already being included in the average. Now, it is possible that I am wrong about this and I have never sat in my car for long enough to really add up some consumption, while also having sat there less than 15 minutes (which causes Car Off state and a reset) after hitting the brake (to enter the PRND state). It I also possible that you are referring to a meter other than the current trip meter, as I don't have those on my dash.

• Any time you put a big demand on the battery, be it departure tax, acceleration, going up hill, accelerating while going up hill... that big bump in the power graph starts its way along the sliding window of whatever integrator you are looking at. You will see a bump in the energy display that moves off to the left of it just as the departure tax moves off to the left of the display. If you stop the car mid trip and then start up again with booming acceleration then for this trip the departure tax is small but the acceleration bump goes into the first couple of cells in the integrator window and looks just like the departure tax.

My point was and is that EVERY time you stop and start (stop signs, stop lights, etc), you are encountering the same "departure tax" (outside of extreme heating and cooling scenarios) as the first time you start from park. It only looks much worse from park because there is so little data to average against. I've already been over exactly how one could prove this out based on their real world experience (by resetting the car or a trip meter at any given stop).

Your comments above suggest that you don't fully understand what is going on here. I hope my responses will help you to. Once you learn how to interpret the meters and graph they will be seen to be a font of information - at least to a geeky guy like me.

On the contrary, I do understand, and I enjoy the data, but I suspect that the average person perusing this thread either fully understands (the type of person who actually calculated their MPG based on fuel added to the tank every time they filled up) or has no clue (the type of person concerned that their average isn't what Tesla or Joe Schmoe said it would be). The latter doesn't benefit from your post without understanding apples to oranges comparison, and the former is already fully aware of its comments. So I actually replied to benefit the latter (as opposed to for this lengthy discussion I told myself I wouldn't get into).

Hills won't make the departure tax disappear. They will simply put more bumps that look like the departure tax on the display with the difference that the departure tax represents an "impulse" as it is billed to the first tenth of a mile (the apparent sampling interval of the car) whereas the hill will appear in bins corresponding to the actual length of the hill (could be a tenth of a mile, I guess).

Firstly, the comment you are responding to was tongue-in-cheek regarding any person actually concerned about the spike on the consumption chart. Secondly, I believe I already pointed this out more than once, but to re-iterate, the departure tax you are referring to will ONLY show up on the consumption chart IF you get in the car and hit the brake to switch from "Car Off" to "PRND." Otherwise that energy consumption is not considered as part of any trip. While I used to hit the brake as I sat down to close the door automatically, and other people may do this, I suspect that the average person sits in the car and closes the door without touching the brake pedal. To be completely redundant, in that scenario, the energy consumed in the period where they are sitting in the car, but not yet shifting into drive is effectively "phantom drain" for them.

 

[mxnym]

Because the intent of my replies was primarily to benefit a specific target audience, I should also respond to this:

For the not so literal minded it means that you are likely to experience lower energy consumption per mile on longer trips as my trip history, which represents a small sample size for sure, clearly indicates. My trip history also indicates the the TREND is for longer trips to register better mileage but that this is only a trend. There is still plenty of variation possible on small trips.

While I'm sure you already understand this, I danced around it in my original reply and completely skipped it in my last reply, and it is worth stating for the benefit of anyone who may not. Longer trips are more likely to include more highway. It is the highway mileage (less stops and starts per mile) that makes those longer trips more likely to have lower consumption, not the number of miles traveled. Shorter trips are more likely to include more city driving. The additional stops and starts included in this city driving are far more significant to the average consumption than the departure tax that may or may not be included in the average you are looking at depending on what actions were taken prior to the start of the trip.

 

[ajdelange]

So as to not get into an extended argument with you, I will acknowledge that we are talking past each other and only respond to a couple points that have anything to do with what I was saying.

Each point was in direct response to something you said. If you think it wasn't then you didn't understand what I wrote. There is really no basis for argument here. There is basis for discussion. Whether you want to have a discussion on some of these points are not is up to you. Or you can, of course, choose to discuss only certain ones that interest you.

The Lexus most likely only shows an average MPG, and only from the time you last reset it. As such, assuming you reset when you fill up (because otherwise you probably never reset or only reset before long trips), the big departure tax ....

You said "...you seem to be acting like BEV is different than an ICEV, when in realty, they aren't." I pointed out that the basic theory is the same and it is. It doesn't matter what each vehicle displays or doesn't display (the Lexus is primative). The departure tax is still imposed. A large departure tax in a Lexus will manifest itself in poor mpg for the entire trip. It is energy/fuel that is used for a purpose other than moving the vehicle and therefore it degrades the AVERAGE miles attained from a unit of energy. Miles traveled divided by fuel/energy will be reduced if you idle an ICE vehicle, run the APU on an airplane, or idle the Tesla.

The problem with this theory is that, at least in my experience, the Wh/mi doesn't populate until you've driven at least .1 miles.

That is correct. Ostensibly the sampling interval is 0.1 mile and I say ostensibly because that is how often the trip data is updated and how often the energy display gets a new point. In fact, of couse, the necessary information could be going onto the CAN bus at a much higher rate and could be on a time basis but the finest resolution displayed to the driver is 0.1 mile.

what is displayed to the driver u In other words, you 've already departed and the cost of some acceleration (which is far more significant than what you were trying to measure) is already being included in the average. Now, it is possible that I am wrong about this

You are correct that the energy taken by acceleration will be added to the energy in the first tenth mile's bin. As will the energy used to cruise for the part of that first 10th after acceleration has ended. Coming out of my garage and going down the driveway (which is a tenth of a mile long so I typically get my first update whilst still in the drive) I'm probably going 20 mpH and according to the ABRP data should use about 33 Whr. That is equivalent to 1.1 minutes of the heater running at 1800 W. If you have run the heater at that level for less than a minute and depart your garage (or the parking lot of your hotel) reasonably then the traction energy required is going to be compartable to the departure tax. If, OTOH, you sit in your car for half an our basking in the warmth, playing the radio and planning trips clearly the departure tax is going to swamp the traction usage run up in that first 10th mile unless you go out of your driveway like A.J. Foyt in Ludicrous mode.

and I have never sat in my car for long enough to really add up some consumption, while also having sat there less than 15 minutes (which causes Car Off state and a reset) after hitting the brake (to enter the PRND state). It I also possible that you are referring to a meter other than the current trip meter, as I don't have those on my dash.

There are two trip "meters". One is labeled "Since hh:mm" and displays distance, time and Wh/mi. The second is labeled "Since Last Charge" and displays distance, kWhr and Whr/mi. The displays do not begin to update until you put the car in D and you have gone some distance which is less than 0.1 mile (so data is indeed apparently recorded at finer distance resolution). As soon as they update for the first time they display accumulated data since, respectively, the time you put the car in D and since you last charged it. The kWhr display jumps by the amount of the departure tax at the first update.

Those displays are, I believe, the key to understanding all this. Not that you can get kWhr from the since D totalizer simply by multiplying Whr/my by the inidicated miles. I still have some questions as to what the "since hh:mm" display is showing. I don't know when exactly it starts totalizing. I think it may be totalizing everything since the last tenth mile. It certainly seems to show the departure tax. While doing a short drive to see it read over 6000 Wh/mi at the first update. I certainly did not accumulate that kind of tax since pushing the pedal or going into drive but I really need to check on this more closely. I really wish there were a Tesla For Dummies book that explained all this. They are presenting the displays to drivers. They should tell drivers what they are displaying.

My point was and is that EVERY time you stop and start (stop signs, stop lights, etc), you are encountering the same "departure tax"

Absolutely right and my message in the first post was that one should try to keep the first departure tax to the level of the subsequent ones. But the advice to minimize stop and go driving still stands. I guess the broadest advice would be to not use battery for anything which does not involve moving the car in the desired direction of travel. Don't sit in the parking lot at McDonald's with the heater on is just as good advice as don't sit in your garage with the heater on.

I've already been over exactly how one could prove this out based on their real world experience (by resetting the car or a trip meter at any given stop).

You don't have to reset trip meters. The "Since hh:mm" display gives you Whr vs time. All you need to do is record that and you can stop and go as much as you want and reproduce the energy display with any boxcar length you like. This gives a pretty concise picture of how you are using energy over distance.

re-iterate, the departure tax you are referring to will ONLY show up on the consumption chart IF you get in the car and hit the brake to switch from "Car Off" to "PRND."

That doesn't appear to be the case but I do need to investigate more thoroughly. The consumption chart starts off with a big bang - at least it always does for me and the bang is bigger if I, for example, tell the car to warm up 10 minutes before I go out to it. I certainly didn't accelerate out of my driveway fast enough to consume kW in 0.1 mile. These high indications have to be departure tax because there is no other way to explain them.

To be completely redundant, in that scenario, the energy consumed in the period where they are sitting in the car, but not yet shifting into drive is effectively "phantom drain" for them.

That does not appear to be the case - not in my X anyway but I will be looking at this further with a mind to better understanding.

 

[dgatwood]

• Heat, A/C, and other accessories use Wh/h, not Wh/mi, so more miles isn't automatically going to lead to a better rating, because sitting in traffic is still using those Wh/h and averaging them back into the counted miles.
• To said second point above, you seem to be acting like BEV is different than an ICEV, when in realty, they aren't. This concept is even reflected in EPA efficiency estimates, highway mileage (Wh/mi is a measure of mileage, just like MPG and L/100kM) is better than city mileage (H/PEV being an exception because the benefits provided have a stronger effect on city mileage).

Yes and no. Heat on electric cars is particularly inefficient because it uses resistance heat rather than a reversible heat pump (or, ideally, a combination thereof). This makes heat considerably more expensive on EVs than on ICE cars, where the heat is actually better than free, as cooling the engine down actually improves its efficiency slightly, at least in theory.

Because the amount of energy needed to reach a given interior temperature is dramatically higher than the amount of energy needed to merely maintain that temperature, on EVs, heating causes a huge departure tax (when enabled).

 

[ajdelange]

Heat on electric cars is particularly inefficient because it uses resistance heat rather than a reversible heat pump (or, ideally, a combination thereof). This makes heat considerably more expensive on EVs than on ICE cars, where the heat is actually better than free....

I jumped in to this thread at No. 419 with the thesis that longer trips offer better energy economy and within dgatwood's comment may lie part of the explanation for that. Suppose we are doing a longish trip in cold weather and have pre-warmed the car after disconnecting shore power. That heat comes from a resistive heater and the energy dissipated by it is the major part of the departure tax. Suppose that within a couple of miles of departure we are on the freeway tooling along at 60 mph (still possible around here when, for example, the government is shut down). Assuming the traction system demands 350 Wh/mi if we are traveling 60 mph it is drawing 350*60 = 21 kW from the battery. The inverters and motors are not 100% efficient - probably more like 90% which means that 2.1 kW of that 21 is being converted to heat. That's around 2 kW which is 4600 BTU/hr or 0.38 of a ton of heat (compare to the portable heaters we use in garages, bathrooms etc.- they typically deliver 1 - 1.5 kW of heat). That heat goes into the glycol flowing through the cold plates in the inverters (and that loop may go through the motors too but I can't picture how) and is then, in warm weather, sent to a radiator to be dumped overboard. I'll bet in cold weather it doesn't go to the overboard radiator but to another radiator in the cabin heating duct work. If the Tesla engineers didn't design it that way they are not nearly as smart as I think it's pretty obvious they are. This also explains why the compressor is not operated as a heat pump in the winter (which puzzled me at first). Why try to pump heat out of cold air and fight Second Law when you have a source of heat at a higher temperature than the load and Second Law is on your side? A simple recirculation pump and a couple of computer controlled valves will save you lots of energy and that's the name of the game here.

It is also evident that initially this "waste" heat is shunted to the battery to warm it up. Once the battery is warm (dashed lines in the regen part of the power display are gone) it is available for heating the cabin. In this sense it's like the ICE situation: waste heat is available to heat the cabin. This is all speculation on my part but it does explain, in part (with the other part being the departure tax) why longer trips are more efficient than short. Once the battery has been warmed you are using less energy to heat the cabin and more kinetic energy is converted back into chemical energy when you have to slow down.

 

[mxnym]

You don't have to reset trip meters. The "Since hh:mm" display gives you Whr vs time. All you need to do is record that and you can stop and go as much as you want and reproduce the energy display with any boxcar length you like. This gives a pretty concise picture of how you are using energy over distance.


That doesn't appear to be the case but I do need to investigate more thoroughly. The consumption chart starts off with a big bang - at least it always does for me and the bang is bigger if I, for example, tell the car to warm up 10 minutes before I go out to it. I certainly didn't accelerate out of my driveway fast enough to consume kW in 0.1 mile. These high indications have to be departure tax because there is no other way to explain them.

That does not appear to be the case - not in my X anyway but I will be looking at this further with a mind to better understanding.

To provide content, these three responses all involve the continued suggestion that energy consumed while the car is in the "Car Off" state is included in the displays. What I have been trying to explain is that the average for that first acceleration (in "Since hh:mm") doesn't include any previous travel (including maintaining speed and possible regen on deceleration) while any subsequent stop and start has prior data to draw the average down. As such, if you generate a chart form that, it's probably going to look like there is a significant departure tax whether there is or not. If the trip meter has enough information, resetting it is one way to witness the difference (or lack thereof) between that first acceleration and any other acceleration. The less safe and not recommended method of powering the car off and on to reset "Since hh:mm" would be the only other way to get this data for reference.

It is possible you disagree with that explanation as well, but it seems to me more like you are either misunderstanding me or simply "not seeing the forest for the trees." I guess I might be suggesting that you need to consider what your control data looks like and/or whether or not you have enough of it.

The reason that I don't think consumption data is outside of the "PRND" state is used for the displays is this: In any given season from one day to the next is that I see relatively comparable numbers on that "Since hh:mm" screen in spite of drastically different behaviors on my part. For instance, I may pre-condition for 2 hours one day and forget to pre-condition at all the next day, but the "unusually" high reading for the first bit of the drive is about the same (in consumption and distance) between those two days. I have also gotten in the vehicle and driven with no accessories active (HVAC off, media off, cold weather package items off, etc) and still see a "unusually" high reading for the first bit of the drive. This is in spite of the fact that, more often than not, I'm in the car putting my seatbelt on as the door closes and trying to shift into drive before the car will even let me. Nonetheless, when I do that one trip and then sit in the car with the HVAC system and media running for 30 minutes before I press the brake (to switch from "Car Off" to "PRND" and start driving) on the next, the "unusually" high reading for the first bit of the trips is again, about the same. Further, when I had ICE vehicles, I got in, started the engine, and started driving. I never let it sit idle at the beginning of the trip. I always had the MPG average displayed, and I always reset it when I filled up the tank. The behavior of the MPG average in my previous ICE vehicles after a fill-up was the same as the behavior of the average in the "Since hh:mm" display of my Tesla (it was "unusually" high), and that's why I don't think the Tesla consumption you're seeing at the beginning of a trip is actually unusually high (and thusly used quotes around unusually everywhere else). It's also why I referenced an old discussion I saw in an ICE forum regarding the Average MPG display being "wrong" if reset from a stop. My experience and observations are what make me think that the departure tax you think is being included in the displays actually isn't. I'm not suggesting that it doesn't exist, just that most (if not all) drivers aren't seeing it in their Tesla displays (in fact, I only assume it might be included if you hit the brake and then sit in the car for less than 15 minutes before shifting to drive).

 

[Propwash]

I just got my 2017 75kw Model x back from its first service Monday. I charged it at home expecting my normal 208 mi city with a max of 235 . instead It charged up to 266mi with room left to go 10% more. Tesla said that rumor has it that the newest update is increasing the battery by 5% , can anyone confirm this?

 

[ps004ynos]

Did you check if it's on the "Ideal Range" setting?

 

[Fishdoc]

I say ajdelange wins the intelectual war here, hands down. He is super smart. I like all is fancy math explanations, although I only understand a small portion of them. Well done and done!

 

[Paul Carter]

And another winter almost over with 20s on.

Less distance vs last winter seen only a slight increase in consumption with more shorter city daily trips.

Yet my winter driving was only 6.6% more than lifetime now increasing my lifetime by 1 Wh/mi.

-	Distance	-	Energy	Avg. Energy	-
Description	km	miles	kWh	Wh/km	Wh/mi
20's	3,543.9	2,202.1	1,058.9	299	481
Prior Lifetime	39,940.3	24,818.1	11,173.0	280	450
Current Lifetime	50,741.6	31,529.4	14,211.3	280	451

 

[Ormond]

My lifetime (21,000 miles) average energy consumption was 313 Wh/mi.

I’m in Florida, so I’m sure that helped tremendously.

 

[ajdelange]

Temperature certainly has a profound effect but the way one drives has an effect too. Again I emphasize that one must look at lots of data, not just single points and again I mention TeslaFi and Stats as a couple of programs/apps that will enable one to get that data. The following plot shows what TeslaFi has collected for me starting in mid January (when I subscribed to it with about 300 mi on the car) to the present (odometer reading of about 1200). It's not a lot of data but the trends are pretty clear.

Salient points are that 100% efficiency (which would mean 295 mi rated range) is realized between 50 and 55 °F (TesliFi collects in 5 ° windows) at which temperature energy consumption is about 320 Wh/mi. Note that this is not the 102000/295 = 346 Wh/mi number suggested by the battery capacity and EPA range. Also note that range appears to increase 2.5 mi for each degree of warming and consumption to decrease by - 3.1 Wh/mi.

The other part of the story is how one drives and that includes, of course, where one drives. The data in the picture are derived from mostly short trips in suburbia. As to how I drive - I'm pretty long in the tooth so I generally resist the impulse to shut down the ICErs trying to cut me off etc.

Given my experience so far I'm a little surprised to see statements (seen here) to the effect that getting the spec performance is a dream and by numbers like those in #432. But I note from the Stats histograms that the median efficiency over S, X and 3 is about 82% (for X alone it appears to be a bit lower).

PS: I have no idea why the last sentence appears in red.

 

[stanX]

my 100 mile trip average was 332. Highway and 20 miles city

 

[Cperry]

I'd say high 300s, haven't really found my stride yet. I'm four weeks in and still randomly taking ludicrous jaunts whether or not I have passengers. I have also been thinking about the AP and how it still seems to stop way too late, making me very concerned about people who are tailgating me, or distracted, running into my lead-foot AP AI. Tesla needs to review these sudden stops. I also think it's either using the brake often where I would be doing one-pedal driving or else raising the regen-braking far higher than it normally goes. I'm betting it's wasting my brakes though.

Overall love the vehicle, but doesn't mean I have to love ALL of it

That would be a nice option on the control panel to choose 1 foot driving and/or the amount of regen braking.

 

[Mewtwo]

X75D Lifetime wh/mile=377 for 10k miles. 2018/8 build so I expect the number to drop further once we reach 2019/8.

I am amazed at how efficient it can be when conditions are right. I am averaging 280-290 wh/mi during the last few days (ambient temp 50-65F, normal HVAC usage, range mode off and everything in normal setting). I didn’t floor it at every light but I didn’t intentionally be gentle with it either.

 

[Mo12]

440 Wh/Mile first 800 miles. P100D with 22” Wheel

 

[Cperry]

440 Wh/Mile first 800 miles. P100D with 22” Wheel

I have the same setup with 5800 miles. Our model X’s are the roomiest so we can’t have it all regarding efficiency. I do enjoy the roomiest feeling car I’ve had Including a Suburban(12 mpg). But the X reminds me of my parents Olds Vista Cruiser a little with second row roof windows. Also probably 12mpg. LOL

 

[MrTeaUSA]

My average is 430 Wh/mi after 3000 total miles. I have MXP100DL 2018 and standard 20in wheels. I set mine at performance mode always. Most of the time is city miles to work daily and by myself. I never get below 400 wh/mi since I get this car. I always wonder how some drivers can get below 400 wh/mi for MX over 5000lbs in weight. This car is rated 98kWh/295miles x 1000Wh => 332 Wh/mi. How do Tesla get this EPGe rating? My Prius get a better 50mpg rating and gas cost saving then my MX electricity cost.