Environmental concerns have, of course, been a key catalyst in the emerging popularity of EVs around the globe. However, a U.K-based study has revealed that larger battery packs in EVs (for the purpose of extending range) may inadvertently lead to a “major increases in particulate emissions” from tires.
The study, which was conducted by Emissions Analytics, an independent emissions testing firm, was designed to provide a additional context to a study previously released in 2020, which demonstrated that tire-wear particulate emissions were 1,000 times worse than tailpipe emissions. With this in mind, The latest study is described as a “detailed analysis conducted in the interim, encompassing a wider range of driving conditions”. The testing firm also performed a chemical analysis of hundreds of new tires to “quantify uncertainties” in chemical composition.
According to Emissions Analytics, in normal driving, tire-wear particulate emissions are 1,850 times greater than tailpipe particulate emissions, as tire wear emissions increase with vehicle mass and aggressiveness of driving style. “That doesn’t bode well for larger EV battery packs, which contribute a significant amount of weight,” explained the firm. “Half a metric ton of battery weight can cause tire emissions 400 times greater than real-world tailpipe emissions, everything else being equal.”
Although tailpipe emissions are much lower on new cars, Emissions Analytics did concede that those emissions are “suspended in the air” for a time, which can wreak havoc on air quality. Tire emissions, on the other hand, settle into the ground (soil and water). The study also revealed that around 11 per cent of the mass of tire emissions is smaller than 2.5 microns in diameter, which is the threshold for airborne particulates that can cause respiratory issues. Moreover, a 2021 study found that tires were a significant contributor to microplastic pollution, which is a growing health concern.
Although a solution has not yet been determined, some innovative companies, like Dyson, are reportedly coming up with “novel ways” to help vehicles clean up as they go.