Woodley’s first big research project, published last year in Nature Sustainability with Nunes as lead author, found EV buying incentives often fail to deliver on the government’s investment. Not only do U.S. subsidies flow to the well-off, with new EVs still averaging nearly $12,000 more per vehicle in 2022 than those powered by fossil fuels, but it turns out tax credits (up to $7,500 in 2023) can incentivize the wrong buyers. Many are led to increase their carbon footprint.
“If you’re somebody who drives a fair amount then you are likely well-suited to drive an electric vehicle,” Woodley said. “If, on the other hand, you’re someone who seldom drives, and the vehicle is mostly going to sit in the garage, then you may counterintuitively be better off owning a gasoline-powered vehicle.”
This is because the batteries that power EVs are responsible for an outsize share of emissions during the manufacturing process. Because EVs are dirtier to build but cleaner to drive, Woodley explained, they must meet certain mileage thresholds before environmental advantages are realized. In the U.S., the typical non-luxury EV needs to log between 28,069 and 68,160 miles before netting any emissions benefits.
“However, many households sell their vehicle before they get there,” he said.
Tax credits, the researchers concluded, should incentivize long-term use of individual EVs. Furthermore, low- and middle-income buyers are, on average, better positioned to realize the emissions advantages of EV drivership (that is, they log more miles relative to the number of cars they own). In April 2022, just after their paper was published, Woodley and Nunes put out a policy memo that recommended extending procurement incentives to the secondhand market. Within days, the Biden Administration announced tax credits for used EVs (up to $4,000 in 2023) as part of the Inflation Reduction Act.
“I wouldn’t be so arrogant as to assume it was because of our work,” Woodley said. “But it was great to see some of our policy recommendations reflected.”