As the Biden administration seems committed to moving the country toward electric vehicles (EVs), and states like California work to ban the sale of new fully gasoline-powered cars in the next fifteen years, the pledge for an EV-powered fleet leaves a question unanswered: How much are consumers actually driving them? New research shows EVs are being driven far less than policymakers think.
“The take-away here is not that EVs should never or will never be our future,” says Fiona Burlig, an assistant professor at the University of Chicago Harris School of Public Policy, “but rather that policymakers may be underestimating the costs of going fully electric.”
Burlig and her co-authors James Bushnell, David Rapson and Catherine Wolfram combine billions of hourly electricity meter measurements with address-level EV registration records in California—home to about half of the EVs in the United States. They find that the arrival of an EV increases household electricity consumption by 2.9 kilowatt-hours per day—less than half the amount assumed by state regulators. Having adjusted for the share of out-of-home charging, the electricity consumed translates to about 5,300 electric vehicle miles traveled (eVMT) per year, roughly half as large as EV driving estimates used by regulators and also half as large as vehicle miles traveled in gasoline-powered cars.
“Regulators have been using unreliable information,” says David Rapson, an associate professor at the UC Davis Economics Department. “They have traditionally extrapolated eVMT from surveys or from a tiny number of dedicated EV meters that are unrepresentative. We used a large sample of households that is representative of EVs in California.”
James Bushnell, a professor at the UC Davis Economics Department, says, “There are several potential explanations for why EVs are driven much less than conventional cars, and unpacking these reasons is next on our research agenda.” He also notes that California’s high electricity prices may be a factor. “It is important to understand why EVs are being driven so much less in order to properly weigh the costs and benefits of EV policy and maximize environmental benefits.”
The research also studied different types of EVs and found that Teslas consume almost double the amount of electricity per hour than the others studied. This is likely due to a combination of factors, including Tesla’s higher battery capacity.
“Along with incentivizing people to purchase and drive EVs, policymakers should be investing in the infrastructure needed to ensure that EVs take full advantage of renewable sources of electricity,” says Catherine Wolfram, Cora Jane Flood Professor of Business Administration at the UC Berkeley Haas School of Business. “Doing so ensures that EVs follow through as a vital pathway for pollution reduction.”