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Comment by justina1 | Hacker News Reader

"Testing" implies the Edmunds report is in some way scientific while it is anything but. They drove the Tesla cars in temperatures as much as 20 degrees colder than the other cars. The EPA ranges are derived by testing in a controlled environment to ensure cars are treated in the same manner. There is variability in range when driving an EV, but this report is deeply skewed and unscientific.

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On the other hand, just seeing the headline I can't say I found it hard to believe - among the major car manufacturers, Tesla seems particularly prone to tweaking the performance numbers they put out. 0-60 figures measured from a rolling start instead of dead stop (that no one seems to be able to reproduce either way), hp figures that are a "peak system power" calculated by adding things up in weird ways and which can't be sustained for any length of time, range figures no one hits in the real world, ... they're very aggressive at this, and it'd be a mistake to think everyone does it this way - for example professional testers regularly exceed 0-60 figures Porsche releases officially.

I've seen a fair amount of professional testers/journalists reprimand them along the lines of "every manufacturer is guilty of this to some extent, but Tesla really ought to tone it down" (e.g. Alexander Bloch, who is generally very positive on the brand). As EV tech is commodifying swiftly and the competition closing in, I expect this to become a larger discussion.

> 0-60 figures measured from a rolling start instead of dead stop

That's pretty normal. One magazine (I don't remember if it is one of the car magazines or Consumer Reports) offers both numbers, from a true standstill and with a slightly rolling start. The latter is much more common, I believe.

Hagarty has a program with Jason Cammisa where this was recently debunked as well [0]. Many manufacturers do this.

[0] https://www.youtube.com/watch?v=JOWKJHvYK54

> range figures no one hits in the real world

I was curious so I looked...

Wikipedia[0] says the energy of a gallon of gas is 33.70 kWh and MPGe is:

    (total miles driven) * (energy of one gallon of gasoline) / (total energy of all fuels consumed)

My Tesla Model 3 LR RWD has a government rating[1] of 130 MPGe, the odometer[2] reads 26,328 mi and 6,727 kWh:

    26328 * 33.7 / 6727 = 131.89 MPGe

So I'm doing better than the rated MPGe. I don't hypermile either, my partner would kindly describe my driving as aggressive.

[0] https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equi...

[1] https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform...

[2] https://i.imgur.com/AACiz7d.jpg

They drove one of the Teslas in a temperature 20 degrees below the warmest temperature they tested in, and that was the Tesla test that underperformed EPA range by the least. Most of the Teslas were tested in the same temperature range as all the other cars and still undershot EPA range.

Source: https://www.edmunds.com/car-news/electric-car-range-and-cons...

Guessing you didn't read the article? This article is saying that when Tesla made those complaints, Edmunds reran the test the way that Tesla suggested and got the following results. Sure, maybe its not a big deal that the cars come up a few miles short of the advertised range under these conditions, but the Tesla ones were the _only_ ones to do so, which is at least interesting.

It would be a very interesting result if it were a controlled test in any way. Tell me, how do you test two cars in real-world driving conditions when one care goes 100 miles further than the other? The longer range car must go through more 'real world' than the other, right? Is Edmunds going on a 10 mile identical loop in identical weather again and again, or did they extend their existing circuit? I guess we'll never know.

Also, they "re-ran" the test? The went from real-world, to a test track, and then _only_ released the results of the 'buffer' range. Then they "re-ran" again but with just two of the cars. Then, they only shared the results for one of the cars they tested (noticeably missing is the data from the other car) calling it "validation" of their results.

You have to at least agree that not releasing the full data on their results is suspicious, no? It seems like they got caught with bad data and a hyperbolic headline ("Every Tesla we've tested has failed to hit its EPA range estimate") and then rushed to find any data that would help confirm their results. That's confirmation bias if I've ever seen it.

Also, the 1st version of the Edmunds report didn't account for the buffer all batteries have while showing "zero range." Turns out the Teslas have more of that buffer. (Though Tesla itself is kinda coy about how big that buffer is, for obvious reasons.)

Yeah, running an EV battery completely dead can be catastrophic to the battery so they try to scare the driver into recharging early. I think the Model 3 LR has about 25 miles of buffer.

Hey man, you try getting headlines (clicks) with the truth all the time.

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