Electric vehicles are one important way for America to use less fossil fuels—driving down emissions that cause climate change and reducing exposure to oil price shocks that threaten economic growth. But as more households buy electric cars, they must also charge those cars, which typically happens after people get home from work. Many EVs charging at once can put a strain on local electric grids. Some utilities are trying to lessen this burden by scheduling EV charging themselves, spreading charging out so that fewer vehicles need power all at once. However, this requires EV owners to cede control of their car to their utility.
Harris Public Policy’s Fiona Burlig and her co-authors investigated whether EV owners would cede control. In a randomized cohort of consumers in the San Francisco Bay Area, fewer than 5 percent of EV households signed up for the managed charging program even when they were given an incentive of up to $40 per month to participate. Far fewer signed up when given less of an incentive.
Those who signed up enrolled through a smart EV charging app that was linked to their EV. Every time they plugged in their EV to charge, they were asked by the app if they wanted to allow the app (i.e., the utility) to decide the best time to draw power based on when electricity was cheapest and cleanest. Even of those who did sign up, a full 20 percent of households never granted the app the ability to adjust their charging. Because so few households signed up, and fewer still granted charging access, the managed charging program could not meaningfully shift EV charging or electricity usage.