As the story goes, all EV range tests are not created equal.
A recent article share with us via PR Newswire is entitled "AMCI Testing Responds to MotorTrend Calling Their Real World Range Testing of the Porsche Taycan A 'Guesstimation'". However, the subtitle reads, "MotorTrend Calls AMCI Testing's Certified Results A 'Guesstimation' —They're Wrong…Here's Why".
Wait, what? Confusing as heck, right? It sort of reads like the famous Abbott and Costello skit, "Who's on First?". In summary, and for the purpose of clarification, MotorTrend asserted that its Porsche Taycan range test was more accurate than AMCI's. Not surprisingly, AMCI responded stating the opposite. You can find the AMCI's full report on the Porsche Taycan's range by clicking here.
MotorTrend recently tested the real-world range of the Porsche Taycan. The publication said:
"Now it's our turn, and MotorTrend does it with proper instrumentation, not guesstimation."
Below are the details related to the two organizations' testing procedures, according to PR Newswire:
- AMCI Testing started with 100% charge and ran both cars in tandem until limp-home battery exhaustion—the only real-world approach to verifying total vehicle efficiency and range
- AMCI Testing ran the maximum-range configuration for five full days and nearly 1,400 miles, then ran the normal-driving configuration for another five full days and another nearly 1,400 miles. That is ten days (two shifts/day) and just under 2,800 total miles of range testing
- MotorTrend's "normal mode" range for the Taycan Turbo S was a partial-charge extrapolation from a single 88-mile loop, and its "range mode" performance was a partial-charge extrapolation from just two 88-mile loops. It appears that MotorTrend never completed (or assessed range over) a single, complete, discharge cycle
- AMCI Testing Certified and reported the results from every mile of testing that was run—MotorTrend employed some type of "data cleaning" according to their description
- In normal mode, AMCI Testing only Certified a combined City/Highway range figure, because that's precisely what we tested. MotorTrend evidently used a further-truncated portion of their one-loop, 88-mile dataset to then break out distinct figures for both city and highway driving (evidently extrapolating from 48.4 miles of city driving and 39.6 miles of highway driving)
The article concludes that MotorTrend did well with its testing when considering "the time and budget constraints of an editorial publication." However, such certified testing "requires significant resources, proven repeatability, and detailed protocols designed to anticipate and address every significant variable."
With that said, the AMCI testing procedure, which appears to be much more extensive, shows an extra 24 miles of real-world range. MotorTrend's tests extrapolate some data and shows less range, but this needs to be taken with a grain of salt. In the end, both organizations are among the many that have found the first all-electric Porsche to offer more range than the EPA suggests.