The EVolution #6: Going back to black?

Dissecting a widely-reported study which claims 1 in 5 drivers bail on their EVs

In automotive and clean energy news publications alike, one headline was a fixture this week: the results of a newly-published study in Nature Energy with sobering news for electric vehicle enthusiasts. Roughly 1 in 5 drivers of plug-in “hybrids” or fully battery-powered EVs in California, it said, wind up switching back to gas-powered cars.

It’s a striking finding—and coverage of the study has focused on the pain points that EV discontinuers cited, namely around convenience of charging and on vehicle driving range. Sure, that makes sense. My day job (and its industry) owes its existence to the need to provide more charging options to the public. And my own recent EV purchase decision was skewed heavily by wanting the longest possible range option. But still… 1 in 5?

Then I read the actual published study by Scott Hardman and Gil Tal, and to me, the eye-popping stat falls apart. In brief, their study worked like this:

1. Among CA households that purchased a hybrid or battery electric vehicle between 2012-2018, 4,167 completed the survey at some point between 2015-2019

2. 384 respondents reported no longer owning their “green car” and subsequently owning “conventionally fueled vehicles” (384—not “1,840” nor “more than 4,000”!)

3. 1,842 respondents (the 384 above included) had, by the time surveyed, made a definitive decision about continuing to own their green car; Hardman and Tal’s ~20% abandonment rate seemingly comes from dividing these two numbers, adjusted slightly for different weightings of hybrids and battery electrics

My bone to pick stems from this methodological note:

We excluded those who have not made any decisions on the ownership of their original PEV as these households may or may not be planning to continue with PEV ownership.

All of the individuals Hardman and Tal excluded are EV owners who confirmed they had not switched back to gas cars. Depending on when these owners received the survey, they could have owned their EV for multiple years (e.g. 2012 purchase, 2015 survey response). Rather than exclude this group—the majority of respondents—they need to be in the denominator. Dividing 384 known “abandoners” out of 4,167 total survey respondents yields a discontinuance rate of ~9%. That’s less than half of what the headlines claim!

I didn’t set out to find holes in this story but here we are (PS: name the movie!)

Hey, I ain’t an academic. If I’m missing something here, please dunk on me. In any case, I’m wary of overreliance on a study of consumers who purchased EVs between 2012-2018—a period of significant technological advancement for electric vehicles. I’d wager that abandonment declined for later-model vehicles during the study, and that it has continued to decline since.

Keep in mind the best-selling battery EV in 2012, among few overall choices, was the Nissan Leaf; it maxed out at a meager 73 miles per charge. In 2021, options from Chevy, Ford, Hyundai, Kia, and Volkswagen get ~250 miles on a charge (and Tesla models typically much more).

The landscape is very different for charging availability, too. For much of the study’s time range, public charging options were extremely limited. In 2012, my employer and Tesla’s Supercharger network were just launching, and other leading networks were then either minor subsidiaries (EVgo) or years away (Electrify America). A majority of today’s ~41,000 public charging stations have been built in the past 3-4 years. So while there’s a lot of work still to be done to provide more and better charging options to EV drivers, I agree with the unnamed Ford official who commented, “Recent efforts are much more encouraging than the article and study imply”.