People who drive a Tesla are a lot less likely to get in an accident in their electric car than when they drive another brand of vehicle they own, according to new research from Cambridge Mobile Telematics.
The Cambridge firm, which monitors driver behavior in millions of vehicles via in-car trackers, smartphone apps, and other devices, reported the research in a presentation Tuesday organized by the Insurance Institute for Highway Safety. The report contrasted how the same drivers performed in different vehicles.
The crash rate per million miles driven was 91 percent lower for a person driving in a Tesla compared to when the same person drove another car they owned, according to the data. That wasn’t the case when the firm compared rates for Porsche drivers: People driving a Porsche were 55 percent more likely to get in an accident than when they drove another brand of car they owned.
There are a variety of possible explanations for the lower crash rate in Teslas, Cambridge Mobile Telematics vice president Ryan McMahon said in an interview. People driving Teslas were also 21 percent less likely to engage in distracted driving with their phone in their Tesla compared to when they drove another car. And they were 9 percent less likely to drive above the speed limit, he said.
Another factor could be the required stops for recharging electric cars. Accidents are more likely on longer trips, but Tesla drivers have to stop and recharge more frequently and for a longer time than gas car drivers stop to refuel, McMahon said. “That could create safer conditions for driving because of fatigue,” he said. “Longer trips are riskier, but there are breaks in the trip from an EV that require people to stop.”
The data didn’t measure the specific impact of Tesla’s controversial self-driving features. Tesla chief executive Elon Musk has promised that Tesla’s full self-driving feature would be available “next year” for the past nine years. And a more limited version of self-driving technology now in use has been blamed for some crashes.
The report was meant to isolate the effect of car design and safety features on accident rates, McMahon said. Studies that typically measure accident rates of different cars may reflect demographic differences in car ownership in addition to car features.
The Cambridge Mobile Telematics analysis also comes at a crucial time, as road deaths are rising at an alarming rate, according to the National Highway Traffic Safety Administration. An estimated 42,915 people died in motor vehicle crashes last year, 10.5 percent more than in 2020 and the highest death total since 2005, the agency reported last week.
In Massachusetts, 403 people died in car accidents last year, up from 327 in 2020, according to MassDOT.
Overall, the increasing rate of crashes and deaths on the road since the pandemic began could be due to an increase in distracted driving, McMahon said. While average speeds and congestion levels have returned to roughly pre-pandemic levels in the Cambridge Mobile data, distracted driving is 35 percent higher.
“We believe that distracted driving is one of the most impactful variables that causes crashes,” McMahon said. “Speed overall on a macro basis skyrocketed during the pandemic, but it has come back to pre-pandemic numbers.”
Still, other researchers have offered alternative explanations for the jump in US traffic fatalities, a trend that has not been seen in other countries that also have high smartphone usage.
“It would seem peculiar if Americans started using their phones differently while driving, causing more crashes, but people in other nations did not,” David Zipper, a visiting fellow at the Harvard Kennedy School, said.
Better designed roads, cameras to deter speeding, and stricter enforcement of drunken driving rules have helped Europe reduce traffic deaths. Such strategies “reduce people’s willingness to drive dangerously even if, frustrated by COVID lockdowns, some might want to,” Zipper said.
Aaron Pressman can be reached at email@example.com. Follow him on Twitter @ampressman.