when people say "tesla overstated their EPA #'s", and "porsche understated their EPA #'s", what exactly does that even mean?
I thought there was a VERY specific test that is done for BOTH cars. As in IDENTICAL testing. And the EPA sets the #'s.
Or are some people unaware?
Watched the video and it explained really well how the testing is done, but it really doesn't touch on why the Porsche gets better range in the real world when it has worse efficiency. A lot of the tests with the Taycan have been on the hwy I want to see a full city driving test
For what it's worth, I've been lurking on the Taycan forums. The consensus among owners there seems to be a few things:
- Porsche used a pre-production BMS with larger top and bottom buffers when doing the EPA testing. Owners report a larger usable capacity than is indicated on the EPA filings.
- Porsche used the 2-cycle EPA test, which imposes a 30% derating on the raw test result (the EPA is trying to encourage manufacturers to use the 5-cycle test by penalizing results from the 2-cycle test).
- Porsche also apparently took an additional voluntary range reduction for some reason (which is completely legal).
- The Taycan has a "range mode" that significantly heats the battery with waste heat from the motor (like older Model Ss). This increases the available energy "Because Electrochemistry"[1] at the expense of battery longevity. Range mode also disables one of the motors to reduce friction.
- However: The EPA does not let you test in range mode unless the car defaults to that mode when turning on. Porsche is required to test with "standard" or "sport" mode because the Taycan remembers your mode selection.
- In contrast to the EPA, most "real world" testing has focused on driving the car in range mode.
- Many owners on the Taycan forum seem to think the Edmunds estimate of the Taycan 4S range is unrealistically high (as I recall, one offered some sort of prize to anyone who could prove it was possible).
Another factor is that the EPA protocol also calls for the car to be driven until it can't maintain speed,
not until the dashboard shows zero miles remaining. In contrast, most "real world" testing ends with "X miles remaining" and then extrapolates to zero. Edmunds' followup testing shows that Tesla is more conservative than other makes in this regard. I would like to see someone test whether zero really means zero on a Taycan.
Editorially, I can't help but wonder if the low EPA range was an intentional marketing ploy:
If Porsche knew they couldn't quite beat Tesla[2], the next best strategy might be to sandbag the official number. Then saturate the media with reports of the car easily beating the EPA's "obviously flawed" test (which it does), as well as apples to oranges comparisons to the competition (like brand new 4S vs. used Performance). Finally, let the public's imagination run wild. The post that started this thread strains credulity, and, while the claims about the Taycan's range have become more and more outlandish, we can't
prove they are wrong.
[1] It's actually more like "because reaction kinetics", but you get the idea.
[2] When you compare apples-to-apples (Taycan 4S vs. Model S LR or a Taycan Turbo vs. Model S Performance), the Tesla still wins the range contest.