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If the official EPA range is....

SoCal Rob

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I trust that the Tesla EPA numbers are accurate yet some (many?) people complain that they cannot reproduce those numbers in the real world. This doesn’t surprise me given the discrepancies between a rigidly-defined test rightly used by Tesla and real world conditions experienced by drivers.

I suspect that other established manufacturers are intentionally choosing the allowed protocol which shows a lower range because they have been dealing with average car buyers for a lot longer than Tesla has. From a customer satisfaction standpoint, not to mention roadside assistance costs, most car manufacturers know consumers expect any range or distance to empty number to be a MINIMUM. Tesla’s calculations may be the best in the business but that doesn’t always help them if most other manufacturers use a less accurate (but still permitted) method which is more likely to under promise and over deliver.

I think this whole disagreement is about typical consumer expectations and perceptions versus hard data. Because Tesla doesn’t behave as old-school car makers do, some consumers will have the expectation of a longer range in real world driving and the perception that Tesla is doing something wrong when they cannot ever achieve it.
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ajdelange

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FYI - if you drive down the east coast on I-95, you will find many places where the speed limit exceeds 65. In Virginia, we have 70 mph limit highways, so driving 75 mph is pretty average on those roads.
We do?

I agree the EPA test for city range is a reasonable benchmark, but we need a real highway range test. As others have posted, highway range is the most important range estimate for BEV owners, because that is when you need to know if you can make it to the next charger. And that is something we should know prior to purchasing a new BEV. Well, at least that is something I want to know before I buy one. Unfortunately, since manufacturers don't tell us that range estimate, we have to wait for independent testers to do it.
I certainly agree that it would be great to have the manufacturers specify EPA range, degradation at 60, 70, 80 etc. But the Monroney sticker has one number only on it. If they made the a, b and c coefficients available that would be great too but I don't think they are going to do that. Thus our knowledge is going to depend on anecdotes posted on fora like this one. If I tell you my consumption goes up 20 Wh/mi cruising at 65 then you need to be asking me about wind, grade road condition and temperature for that to be meaningful. I just say get to know your car/truck. I know to expect 300 - 310 Wh/mi on a trip that involves 65 mph speed limit freeway.
 

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As an engineer you should understand that the highway range has to be less than the combined range and that, therfore, a Monroney sticker that displays the highway range is not displaying the EPA range.ere the speed limit is 75 or around one of the metropolitan areas where it is 55 or 65?
Which begs the question of why stated mileage figures for ICE vehicles differentiate between highway and city driving and EV range estimates do not.
 

Gshenderson

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For me, the only value in EPA numbers is the ability to compare different model cars against each other. Is the one I’m interested more or less energy efficient than another? That’s why I’d like to see more standardization in the testing. In addition, given the impacted wind drag on an EV, especially at higher speeds, I would like to see the EPA testing include some way of measuring this. As has been previously mentioned, road trips at highway speeds is where range becomes most critical for most EV drivers.

My driving habits (usually 9 over speed limit, mountainous terrain, cold winters, etc) make it such that my actual numbers will vastly different than EPA numbers. I will simply use tools likely the trip computer in the truck, route planner like A Better Route Planner and real life experience to translate the rated range to real world range. I’ve done that in my Tesla for 6 years, so it’s nothing new.
 

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SeaGeo

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I'm afraid we have to add you to the list of those who don't understand what the EPA rating's purpose is. It is not intended to reflect real world performance at highway speed. It is intended to reflect performance against 5 profiles which blend highway and city driving. As the average speed over these profiles is appreciably lower than that of a pure freeway trip it is to be expected that there will be additional burden on the battery when driving at highway speed relative to when driving the EPA profiles. Thus it is irresponsible for Porsche to sandbag (IMO) and responsible of Tesla to report what EPA wants them to report.


As an engineer you should understand that the highway range has to be less than the combined range and that, therfore, a Monroney sticker that displays the highway range is not displaying the EPA range. Users should NOT expect to get the EPA range on the highway. The problem seems to be that many do.

This problem could be solved by redefining the test requirement to test against highway conditions but which highway conditions? Out west where the speed limit is 75 or around one of the metropolitan areas where it is 55 or 65?
No. I fully understand what the EPA range is simulating. Statements that you make like that are also what irritates people. I specifically noted in my edited response that Porsche is accounting for differences in the use case that matters, and that it's different than what is noted by the EPA combined range. What won't happen here, is me telling you that you don't understand that literally everyone who's addressing this with you is that the issue here isn't a us understanding the test (most people here seem to), it's a communications issue that manufacturers are addressing on their own in one way or another. I'm wouldn't say that because I suspect you realize that it's a communications issue and you're just being arrogant in believing other people don't understand what the strict simulation of the EPA sequence is trying to capture.

What it not happening is the Monroney sticker doesn't provide enough context for drivers. It presents range as a *single* number on it (see below). And it does *not* say "here's your range under a combined condition, you won't get this on the highway." It gives MPGe for city, combined, and highway, but it doesn't give range for all three. There an implication that the range is for combined, but it is *not* clearly stated. Further, 90%+ of people won't know what in the hell to do with that MPGe to convert it into range. Should the EPA adjust this? Yes.

Do I understand what's being shown on the sticker, and what's being tested because I'm an EV nerd and an engineer? Yes. Does the average consumer? No. What I am communicating (and others) is that to the *average* consumer, the Monroney stick is what they expect to get. When does the average consumer run into range issues? On the highway. The issue is both inconsistency between manufacturers, and setting expectations. Porsche is being *more* responsible because they (seemingly) want to make sure that when Bill the wealthy dentist buys a Taycan, he will get the range on the sticker in most (if not all) conditions. Porsche is not the only manufacturer doing this.
Rivian R1T R1S If the official EPA range is.... 1624294039807


It's a communications and consistency issue (and you're only acknowledging the latter by saying Porsche is sandbagging it). You're point of view is you think Porsche (and others) are being irresponsible, but they're trying to provide closer to a guaranteed quality of service (range) for their customers in the only use case where range generally matters because they understand that their customers likely don't understand what's going on with EPA range testing. Tesla seemingly doesn't give a shit other than to provide bragging rights for marketing purposes.

And to clarify, that last paragraph, and everything about what the intent of what both Porsche and other manufacturers are doing is reading the tea leaves and a presumption because I haven't had specific discussions with them. But it seems pretty obvious. But I don't want you to take my statements of assumed intent as me having had an explicit conversation with those manufacturers because.
 

ajdelange

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I trust that the Tesla EPA numbers are accurate yet some (many?) people complain that they cannot reproduce those numbers in the real world. This doesn’t surprise me given the discrepancies between a rigidly-defined test rightly used by Tesla and real world conditions experienced by drivers.
I think that's part of it. They don't understand what that number on the Monroney sticker means. I'm sure I didn't when I first looked at BEV. My car's said 351 and I just assumed I could go 351 miles on a charge.

The thing is, I can. We just drove 600 miles up here on interstates most of the way. Overall our consumption was 291.24 Wh/mi. That's 3.27% higher than the rated consumption and means that the rated range is 340 miles as opposed to 351. I think that's pretty close. It represents "efficiency" of 96.87%. Now you are probably thinking "tailwind". No tailwind. Or that I drive like a little old lady. Well I don't go more than 10 over the speed limit but I don't go under it either unless I have to for traffic congestion. So I find the car to operate within a couple of percent of the EPA rating. At the same time I see that the average Tesla driver experiences 90%. That's more loss than I see but still not that much. I conclude that the bulk of the drivers are in places where the speed limits are higher overall and/or that I am indeed a little old lady because I don't drive more than 10 over.

I don't see what the fuss is. What do they expect? Well I guess the answer is they expect to see what it says on the Monroney sticker no matter how they drive.
 

SeaGeo

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EV range estimates do:

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That actually doesn't show multiple range values. The person you responded to say "ev range estimates..." not "ev efficiency estimates." Apparently you don't know the difference between range and efficiency. (I know you do, but you weren't being exact, and this is the sort of response you give people.)

The sticker shows different efficiency values in a non-sense unit the EPA adopted several years ago to try and make comparisons between ICE and hybrid vehicles more readily possible. There is *one* range value presented on that sticker. It doesn't even stay which condition the range is representing. Is it City? Highway? Combined? What does Bill the Doctor do with that? Most people wouldn't figure out to take their 81 miles, and scale it down by the ratio of highway to combined MPGe even if they *knew* that the range was for the combined condition.
 

SeaGeo

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I'm sure I didn't when I first looked at BEV. My car's said 351 and I just assumed I could go 351 miles on a charge.
Exactly.
 

ajdelange

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In addition, given the impacted wind drag on an EV, especially at higher speeds, I would like to see the EPA testing include some way of measuring this.
They do. They haul the car up to I guess around 90 mph and let it go measuring speed or distance or perhaps even acceleration vs time. From this the retarding forces (drive train, drag, rolling resistance) can be calculated and a curve relating speed to retarding force developed. That's programmed into the dynamometer during the range tests.
 
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SoCal Rob

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I think that's part of it. They don't understand what that number on the Monroney sticker means. I'm sure I didn't when I first looked at BEV. My car's said 351 and I just assumed I could go 351 miles on a charge.

The thing is, I can. We just drove 600 miles up here on interstates most of the way. Overall our consumption was 291.24 Wh/mi. That's 3.27% higher than the rated consumption and means that the rated range is 340 miles as opposed to 351. I think that's pretty close. It represents "efficiency" of 96.87%. Now you are probably thinking "tailwind". No tailwind. Or that I drive like a little old lady. Well I don't go more than 10 over the speed limit but I don't go under it either unless I have to for traffic congestion. So I find the car to operate within a couple of percent of the EPA rating. At the same time I see that the average Tesla driver experiences 90%. That's more loss than I see but still not that much. I conclude that the bulk of the drivers are in places where the speed limits are higher overall and/or that I am indeed a little old lady because I don't drive more than 10 over.

I don't see what the fuss is. What do they expect? Well I guess the answer is they expect to see what it says on the Monroney sticker no matter how they drive.
I think the fuss is over the fact that most people have an expectation that things will get easier over time. At one time if you wanted to drive you had to understand every aspect of how the car and ICE worked: from hand-crank starting to setting spark advance to adjusting the choke to keeping the fuel tank pressurized.

To many people who are new to BEVs, the extra work involved in calculating EXACTLY how far they can go on a given route with anticipated weather and traffic conditions is harder than what they’ve experienced in their driving experience when taking ICE road trips. The fact that some of us enjoy the mental exercise of doing the calculations doesn’t change the fact that this is a downside for typical drivers.

So, just as some people enjoy looking at paper maps and plotting routes for a road trip, most people today use car- or phone-based navigation to do that work for them. They find no joy in dealing with maps just as they find no joy in calculating range.

At this point ICE drivers are used to starting their car and looking at their instrumentation for an indicated range and comparing that to the trip distance. They know at a glance if they should fill up before leaving, get fuel along the way, or not worry about fuel at all. If a BEV doesn’t behave this way reliably, there is a high likelihood that a typical person will think, “EVs are inferior!” or “My car manufacturer lied to me!” and not, “I need to change how I evaluate trip distance, conditions, and total range.”

You can show these people that the information is there, if only they’d use it as you do. Only a tiny fraction of people have any desire to do so.

edit: fixed a typo
 

Whataboykie!

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Two friends have LE reservations and not on this board. Both have F150 reservations and are so close to dropping their Rivian spots, getting their deposit back and buying the Ford. They been looking more and more at the Ford trucks this week and are envisioning owning one.

Whatever you’re doing Rivian, it’s not working and you’re ready to lose customers.
Yes I am also very disappointed with Rivian. I ordered mine in Nov 2018 and haven't heard a thing. You'd think that with more than $8 billion in investments, they'd be eager to deliver vehicles as promised. Luckily I also ordered a Cyber Truck in 2019, so I might just get that before my Rivian the way it seems to be going.
What ever happened to "first come first served" as promised? I'm near NY and Philly, so not in the boonies at all!
 

ajdelange

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You can show these people that the information is there, if only they’d use it as you do. Only a tiny fraction of people have any desire to do so.
I sometimes worry that the OEMs won't dumb things down enough for the general public.
I sometimes worry that the OEMs will dumb things down enough for the general public.
 

SoCal Rob

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I sometimes worry that the OEMs will dumb things down enough for the general public.
I realized that ship sailed in 2004 when I owned a sports car with an oil pressure gauge which was basically a damped mechanical warning light. Once the oil pressure switch (not variable pressure sensor) closed the needle would slowly (because it was damped) move to “Normal” so it gave the illusion of the oil pressure rising. It had the shortcomings of a warning light but without an eye-catching rapid transition between the two states or the ability to blink to really get your attention.

Since then I’ve seen the elimination of automatic transmission dipsticks (consequence: difficult to determine level or check fluid color and REALLY difficult to add fluid) and engine oil dipsticks (consequence: have to trust a sensor for oil level and impossible to check oil color/state without an oil change) in the name of making things easier.

We all have our own thresholds for what we consider acceptable. I have an issue with anything which prevents me from seeing the real state of ”health“ of a mechanical system where being isolated from the facts can lead to dire consequences.

I’m perfectly fine with a trip computer which gives me a range which is conservative so the worst consequence is having more range than you expect.

It sounds like people see the opposite effect (less range than they expect) with Teslas more than other EVs, and that is why they are annoyed.
 

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That actually doesn't show multiple range values. The person you responded to say "ev range estimates..." not "ev efficiency estimates."
Thank you, SeaGeo, for actually reading what I posted before responding.
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