Rob Mauer's early objections came from Edmunds knowingly introducing variations in conditions which would disadvantage the Teslas (like lower temperatures) but not being very clear about that.
Also, Edmunds originally did this thing, where they didn't account for the "zero remaining" buffer. Teslas put more of their capacity under the reading "zero remaining," to encourage low battery level drivers to seek charging sooner. Edmunds also had to be called out for that.
Temperatures in the 40s are not "low temperatures." It has been in the 40s at night in Los Angeles for the past month, and that is in one of the most favorable locations for EVs.
Tesla absolutely should be called out for giving range estimates that require unicorn temperatures. Edmunds testing more accurately reflects real world usage, aka, what a normal person would get if they weren't trying to artificially goose their measurements.
Edmunds tested all of the cars the same way: on roads, highways, and freeways in the LA area. It tested each car using the same settings for A/C, etc.
Tesla simply failed to live up to its marketing claims. Again. Even after Edmunds re-tested the vehicle to accomodate some of Tesla's requests. (And in fact, Edmunds notes that no Tesla has ever reached or exceeded its EPA rating in its tests, which is unique among all automakers, ICE or EV.)
In contrast, most of the other EVs outperformed their stated EPA ranges, and even with zero range buffers Tesla still underperformed its EPA ratings, while the other vehicles simply exceeded their EPA ratings even more once their zero-range buffers were included.
How does Edmunds conduct its testing?
The roads
Edmunds drives on specific road routes that cover both highway and city driving around the greater Los Angeles area. We aim for a mix of 60% city driving and 40% highway, assuming that most electric vehicle owners will likely spend more time in stop-and-go traffic than they will on the open highway. Since no electric vehicle has exactly the same range, the route length is adapted to suit each vehicle.
The methodology
In EPA tests, a vehicle is run in the default settings at startup. If there are more efficient drive modes available, or if you can increase the level of regenerative braking, but the vehicle doesn't default to these settings, they won't be utilized. Edmunds' standard practice is to use the most efficient drive mode as long as it doesn't affect safety or practical comfort levels, such as deactivating the climate control system or significantly reducing power for accelerating or maintaining appropriate highway speeds.
We run with windows up and the climate control set to auto at 72 degrees, and we maximize regenerative braking during stops. We follow the posted speed limits and keep within 5 mph of them, traffic and conditions permitting.
> Edmunds tested all of the cars the same way: on roads, highways, and freeways in the LA area. It tested each car using the same settings for A/C, etc.
That's... fairly generous to Edmunds. There was almost a 20 degree difference in temperatures between cars.
> How does Edmunds conduct its testing? The roads [...] driving around the greater Los Angeles area
Which can exaggerate the difference between cars. Suppose Car A has just enough battery to coast over the top of Angeles Forrest Highway and then regen down the other side. Car B rolls to a stop 1 ft from the top.
Most people would say these two cars have virtually the same range, but a test on hilly public roads could turn that into a 20+ miles difference in range.
They tested all of the cars in the same geographic location, following the same course on roads, highways, and freeways, ever time, during the same month. No other brand had the same systematic issue with overstated mileage despite the temperature differences, which affected all of the Teslas, not just the one driven during the coldest days (which were still no lower than 45 degrees F).
Most people would say these two cars have virtually the same range, but a test on hilly public roads could turn that into a 20+ miles difference in range.
That would have benefited Tesla, as their vehicles have larger batteries than their competitors. And yet...they systemically underperformed their EPA ratings.
Other comments mention that abusing the "zero remaining" buffer could damage the battery. On the one hand that doesn't sound ideal for a range someone may want to use more often, on the other hand the screen issue older Teslas had came with a maximum expected life of only seven years which software updates exaggerated down to three. So you can probably expect the car to fall apart long before the battery does.
https://www.youtube.com/watch?v=rb1toreNTrU
Rob Mauer's early objections came from Edmunds knowingly introducing variations in conditions which would disadvantage the Teslas (like lower temperatures) but not being very clear about that.
Also, Edmunds originally did this thing, where they didn't account for the "zero remaining" buffer. Teslas put more of their capacity under the reading "zero remaining," to encourage low battery level drivers to seek charging sooner. Edmunds also had to be called out for that.