UC Davis Institute of Transportation Studies

This study examines the relative economics of electric vehicle operation in the context of current electricity rates in specific utility service territories. The authors examined 14 utility territories offering electric vehicle (EV) rates, focusing on California but also including other regions of the United States. The consumer costs of EV charging were examined in comparison with gasoline price data, geographic location, and during three highly variable gasoline price periods of July 2008, January 2009, and July 2009. In a switch from a conventional 23 mile per gallon (10.2 liters/100 kilometers) vehicle to a 300 watt-hours/mile electric vehicle driven 10,000 miles (16,100 km) per year, the study finds that savings in fuel costs ranged from approximately $100US to $1,800US annually, with considerable geographic variation and with higher-end values mostly in Summer 2008 when gasoline prices were relatively high. Charging off-peak instead of during peak periods saves an average of only a few hundred dollars US per year, rendering the incentive to charge off-peak a relatively small one except perhaps during some summer months when the on-peak prices are especially high. Gasoline price variances have a larger effect and switching from a low fuel economy conventional vehicle to the reference EV (compared with a switch from an already efficient vehicle) presents the highest savings level. The West and Midwest are generally the most favorable regions for EV economics, when EV charging rates and gasoline prices are considered together.