Porsche Taycan EPA range

[AlanSubie4Life]

That link to the independent test is also pretty misleading. They don't provide any information on a highway test in range mode! Arguably that is what matters the most to people who want to use an EV for road trips, which is the only place range usually matters. They have a city/hwy test in normal mode (no details on the test that I could see), and a city-only test in range mode (which is where the 288 number comes from - probably a Model 3 would get 400-450 on that same test).

800 rated miles per hour for the Porsche Taycan at a 350kW charger....about 1000 rated miles per hour for the Model 3 at a 250kW charger.

I find it interesting that the highway efficiency is better than the city efficiency. Unusual for an EV and must be related to the gearbox? Or maybe their static electronics power draw is enormous?

On the upside, driving in cold conditions and using the HVAC isn't going to make nearly as much a % difference with this Taycan as it does with, say, a Tesla SR+!

 

[Eno Deb]

The WLTP is based on the extremely unrealistic stop and go pattern of the old NEDC cycle, which was itself a modification of the really unrealistic ECE ("urban drive cycle" below) cycle. These cycles may have originated in actual driving conditions in certain metro areas but their selection for determining range and ICE emissions/mpg ended up being a result of industry lobbying. The EPA cycles are based on somebody doing some driving in LA back in the 60s (city cycle) and in Michigan in the 70s (highway cycle). They've added extra tests and argued over fudge factors over the years, at least in the US.

I have no idea if that is accurate or not, but while this may explain in general why WLTP is on average by about 12% more optimistic than EPA for other EVs, it does not explain why the discrepancy is so much bigger (39%) with the Tayan.

 

[M3BlueGeorgia]

Not sure how you arrive at that conclusion. The EPA cycle reaches a top speed of 60 mph, the WLTP cycle 82 mph.

David Roper did some statistical analysis on EPA vs. WLTP numbers for EVs a while ago, with the result that WLTP numbers are on average by a factor of about 1.12 higher than EPA numbers. In case of the Taycan Turbo, it's about 1.39. I wonder what might cause that.

In any case, this will be a big marketing problem for Porsche in the US.

I'd hazard a guess that the WLTP figures might be a little cooked. We are talking about part of the VW Group, after all.

 

[AlanSubie4Life]

Porsche apparently doesn't quite believe it either:

The Porsche Taycan Turbo's EPA Range Of 201 Miles Is So Bad Porsche Requested An Independent Test

Will be interesting to see some real-world impressions. I have never seen such a big discrepancy between WLTP and EPA numbers.

I found the title of that story to be weird...it kind of implies that Porsche is not the one doing the original EPA test...which of course they are doing themselves. It's like "oh, the EPA screwed us with their test...we had to go to an independent lab to have them test it" - that's what it sounds like to someone who has no idea how things work. What actually happened is Porsche did a carefully optimized EPA test under controlled conditions according to the EPA rules in their own testing lab with Porsche engineers present, and when that predictably produced a terrible result, they went with the AMCI random number generator/inflator using a totally different cycle and set of rules (which are not easy to find), which provides no additional information.

 

[arghx7]

The EPA audits cars. They can take a Taycan and check the road load coefficients (measure of drag and weight) or run it at their lab in Michigan.

 

[M3BlueGeorgia]

I found the title of that story to be weird...it kind of implies that Porsche is not the one doing the original EPA test...which of course they are doing themselves. It's like "oh, the EPA screwed us with their test...we had to go to an independent lab to have them test it" - that's what it sounds like to someone who has no idea how things work. What actually happened is Porsche did a carefully optimized EPA test under controlled conditions according to the EPA rules in their own testing lab with Porsche engineers present, and when that predictably produced a terrible result, they went with the AMCI random number generator/inflator using a totally different cycle and set of rules (which are not easy to find), which provides no additional information.

Also, I'd be surprised if Porsche were actually surprised by the result.

Since they were always intending to sell in the USA, they would have been running simulations at multiple points during the development process and they'd be able to predict the EPA range within a few percent even before they had a driveable car.

Like Audi and their 204 EPA mile range, Porsche have kept this information secret until after all the initial marketing push was complete.

 

[Eno Deb]

I'd hazard a guess that the WLTP figures might be a little cooked. We are talking about part of the VW Group, after all.

If they are so devious, why wouldn't they also have "cooked" the EPA tests?

 

[Eno Deb]

I found the title of that story to be weird...it kind of implies that Porsche is not the one doing the original EPA test...which of course they are doing themselves.

This isn't necessarily true. Many manufacturers outsource the tests to independent labs. This is, BTW, also true for WLTP (and caused delays in Europe last year because there weren't enough certified test labs for the new test cycles).

 

[arghx7]

The certification tests require witnesses to sign off that they were being done correctly.

 

[M3BlueGeorgia]

If they are so devious, why wouldn't they also have "cooked" the EPA tests?

Having a 201 mile EPA range suggests that they've been working hard to get it just across the 'magic' 200 mile number.

The EPA tests are very specific, so Porsche's flexibility is limited, but we could probably safely assume that they've pushed the envelope as far as they could to get the number they now publish.

 

[AlanSubie4Life]

The EPA audits cars. They can take a Taycan and check the road load coefficients (measure of drag and weight) or run it at their lab in Michigan.

Maybe this is what you were saying, I get the impression manufacturers always do the testing themselves and self report. Never mind...missed a bunch of posts above...

Many manufacturers outsource the tests to independent labs.

Sure (that's actually what I meant by their "own" testing lab), but reasonably sure they're done with close interaction with Porsche and their engineers. Obviously Porsche may not want to assume the burden of owning their own complete testing facility. No idea what they have specifically decided to do in this case.

In any case the numbers are likely all legit.

I assume the difference has something to do with the effect of the gearbox and how it affects the WLTP cycle differently. There was also a range of results in that correlation test - ~1.12 was just the average as I recall (checked...stdev was ~9%). So definitely this seems like a statistically significant outlier.

Or maybe they have massive "on-drain" which would give worse results for a test that takes longer runs at a lower average speed. (I'd have to familiarize myself with WLTP to see whether this effect would "go" the right direction - I'm only vaguely familiar with the EPA cycles and how that test is done, never have looked at WLTP.) Edit: Looks to me like the average speed of WLTP is 46.5km/h while the weighted average of the UDDS and highway cycles under EPA would probably be lower average speed, so it would look worse if there were enormous static overhead. But not sure it's anywhere enough to explain the result. EDIT: fixed the km/hr number above. I read it as mph. Looks like the average speeds are pretty similar for the tests.

If I'm calculating correctly, assuming 10% charging losses, the 14kWh/100mi discrepancy with the Model S at an average test speed of 45km/hr would require static losses of around 3.5kW in Taycan to explain the discrepancy, so that doesn't make much sense! 14kWh/100mi*0.9*1mi/1.609km*45km/hr = 3.5kW

 

[hydro 481]

201 miles for a 200K EV is just pitiful. What does that mean for the base Taycan with smaller battery pack? 150 miles?

 

[AlanSubie4Life]

201 miles for a 200K EV is just pitiful. What does that mean for the base Taycan with smaller battery pack? 150 miles?

It means bad bad things probably.

Nonsensical verbiage from electrek.co:

"Hopefully, like Audi and Jaguar before them, Porsche’s efficiency is so bad because they are being conservative with their energy capacity that they let people access in the Taycan."

Umm...that's not how efficiency works. Porsche's efficiency is bad because they have a very inefficient drivetrain. Maybe they will be able to tweak it a bit in the future with software updates, but it's in a big hole and they'll likely have to redo the platform from scratch. By 2024 they will likely have a competitive offering. Unlike with an ICE, better efficiency in an EV likely means better performance in many situations (but yes there are caveats).

 

[hydro 481]

It means bad bad things probably.

Nonsensical verbiage from electrek.co:

"Hopefully, like Audi and Jaguar before them, Porsche’s efficiency is so bad because they are being conservative with their energy capacity that they let people access in the Taycan."

Umm...that's not how efficiency works.

I guess it must be that difficult to achieve high performance AND good range? If the Roadster comes out with a true 600 mile range, it’s going to put the Taycan to shame.

I’m not even sure what that article is implying. That Porsche is reserving a portion of the battery for some reason?

 

[AlanSubie4Life]

That Porsche is reserving a portion of the battery for some reason?

They probably do reserve a portion of the battery (they do on the eTron)...and based on the Wh/100mi and assuming charging losses of 10% they're probably reserving about 5kWh of the 93kWh battery. We'd have to see the test details to know.

But it doesn't matter at all. That would only affect the range, it does not affect the efficiency (which is extremely poor).

I downloaded the EPA datafile. Download Fuel Economy Data

Adding to the comedy, the Taycan Turbo (not the Turbo S) has been derated to 201 miles (from 202).

Presumably the Turbo S will have even worse efficiency, while the regular plebeian Taycan will have worse range. Though maybe the front inverter being different on the Turbo S will actually make it more efficient. We'll see I guess.

Weirdly, the datafile suggests that the Taycan has just 1 motor (that is just an error). I couldn't see any other useful info in there (the actual battery capacity in kWh is not given and you can't multiply voltage by Ah). But the battery is something like 93kWh, and they probably don't use all of it based on the numbers.

 

[Uncle Paul]

The lower range may be caused by the design.

Porsche has "tuned" the car for high performance, perhaps at the expense of economy.
Perhaps they allow more current to flow, to give the feeling of a more powerful motor, thus adding enjoyment to the driving experience.
It could also be that the two speed transmission does not shift during the test cycle, and that it runs the entire time in the lower (less efficient) gear ratio.

Just some guesses as why the disappointing EPA figures.

 

[hydro 481]

I just received this email from Porsche:

Dear Taycan Enthusiast,
Porsche will soon add a new chapter to its history as the new Taycan arrives in the United States. Among the first Taycan models to arrive will be the Model Year 2020 Taycan Turbo.
The estimated EPA range for the Taycan Turbo is 201 miles.
In preparation for the Taycan launch in the United States, Porsche asked AMCI Testing to conduct independent tests to evaluate the Taycan Turbo range to help customers make more informed decisions. AMCI Testing is an independent automotive research firm, specializing in unbiased evaluations of automotive products.
Tested on AMCI Testing’s “City/Highway Commute Cycle” route on public roads in and around Southern California, the results were calculated by averaging the vehicle’s performance over five test cycles. The Taycan Turbo achieved a range of 275 miles.

 

[Uncle Paul]

Gotta be the truth...no way they would lie about something like this

 

[jerry33]

If they are so devious, why wouldn't they also have "cooked" the EPA tests?

The EPA tests do get audited if there is any suspicion of cooking and also just randomly.

 

[willow_hiller]

I just received this email from Porsche:

Dear Taycan Enthusiast,
Porsche will soon add a new chapter to its history as the new Taycan arrives in the United States. Among the first Taycan models to arrive will be the Model Year 2020 Taycan Turbo.
The estimated EPA range for the Taycan Turbo is 201 miles.
In preparation for the Taycan launch in the United States, Porsche asked AMCI Testing to conduct independent tests to evaluate the Taycan Turbo range to help customers make more informed decisions. AMCI Testing is an independent automotive research firm, specializing in unbiased evaluations of automotive products.
Tested on AMCI Testing’s “City/Highway Commute Cycle” route on public roads in and around Southern California, the results were calculated by averaging the vehicle’s performance over five test cycles. The Taycan Turbo achieved a range of 275 miles.

Not accusing Porsche of fitting a vehicle with a cheat device or anything outlandish like that, but...

Do car companies get to pick the particular vehicle used for the EPA test? Or does the EPA pick it?

I imagine for any independent test, Porsche would have had to provided AMCI with a specific vehicle for testing.