It’s one thing for something to make sense intuitively, nevertheless it’s one other thing altogether to have the option to prove it. So, while the tire and brake dust that electric vehicles generate could be a problem, without exhaust continually spewing out of the back, it would not be crazy to assume air quality would improve if more people drove EVs. Nevertheless, since EVs only account for a small percentage of latest automotive sales within the U.S., are they even popular enough to make a measurable difference? Well, our friends over at The Autopian just covered a brand new study claiming that is exactly what’s happened in California.
That study was published within the Lancet Planetary Health scientific journal and was conducted by the University of Southern California’s Keck School of Medicine and claims to be “the primary real-world study showing statistically significant reductions in observed NO2 air pollution related to the continuing transition to light-duty electric vehicles over time.” Using satellite data provided by NASA, researchers studied 1,687 different “ZIP code tabulation areas” spread across the state. And in the long run, they found that EVs really did contribute to a noticeable drop in nitrogen dioxide levels.
What’s perhaps more surprising, though, is just how few zero-emissions vehicles it took to cause a statistically significant reduction in NO2 pollution. If you would like to cut NO2 levels by 1.1%, you do not need just a few thousand EVs in your neighborhood. Apparently, on average, you simply need 200. So while those Tesla drivers do still make world worse by propping up the CEO’s fortune with their purchases, it is best to still thank them for making it somewhat easier to breathe.
No study is ideal
As with all studies, you’ve to account for other aspects in your evaluation, and while it’s plausible there is likely to be just a few nits to choose with the researchers’ methods, they no less than tried to account for all the pieces from the “non-linear effect of calendar 12 months” to “time-varying population size, socioeconomic status, fuel price, and telecommuting patterns,” in addition to the “time-varying variety of ICEVs.” And because the pandemic really threw a wrench into just about all the pieces, they excluded data from 2020 entirely.
There’s also more to air pollution and vehicle emissions than simply nitrogen dioxide, and it’s plausible that future studies may not show as significant of a discount in other greenhouse gasses. The authors also readily admit the study has its limitations, especially because the satellite data they used wasn’t available until 2018, meaning they were only in a position to study the years 2019 through 2023. As for why they only focused on NO2, the authors wrote, “We focused on NO2 since this pollutant arises from the combustion of fossil fuels, primarily from vehicle emissions, and the one source of NO2 from local vehicle operation is exhaust emissions, which fully electric vehicles would not have. Effects on other air pollutants merit further study and is likely to be complex.”
Still, it’s great to see evidence that EVs reduce NO2 because, because the authors put it, “traffic-related air pollution exposures, including NO2, negatively affect cardio-pulmonary health and contribute to premature death.” In spite of everything, Volkswagen wasn’t just forced to spend billions of dollars atoning for its sins since it broke the law. Its dirty diesels spewed a pollutant that actively made life worse for everybody else.
This Article First Appeared At www.jalopnik.com
