A detailed, city-level multivariate regression analysis of EV penetration in California has found a link between electric vehicle uptake and many underlying factors. A team at the International Council on Clean Transportation (ICCT) found that electric vehicle model availability; public electric vehicle charging network; local promotion activities for electric vehicles (e.g., outreach events, informational websites; electric car sharing services; and government and fleet programs) and median income in each city to be correlated significantly with new electric vehicle sales share. They cautioned that causality could not be determined within the analysis.
The team drilled into the activities of the 30 California cities with the highest rates of electric vehicle penetration, examining how local organizations—regional and city governments, utilities, businesses, and nonprofits are promoting electric vehicles through a wide array of activities. In these 30 cities, electric vehicles account for 6% to 18% share of new vehicle sales—this is 8 to 25 times that of the US average in 2015. These vehicle markets range greatly in size, from hundreds of electric vehicle sales up to approximately 4,000 (San Jose).
Some of the examined factors (California Clean Vehicle Rebate claim rate and the prevalence of single-family homes) were not linked with electric vehicle uptake. Other factors for which data was not available (such as the income of electric vehicle purchasers specifically, rather than city-level median income) or that cannot be quantified (such as cultural differences between cities) could be influencing electric vehicle uptake in these cities, the authors observed.
Based on the analysis, the ICCT team drew three overarching conclusions:
Comprehensive policy support is helping support the electric vehicle market. Consumers in California benefit from federal and state electric vehicle incentives, as well as from persistent local action and extensive charging infrastructure. The Zero-Emission Vehicle program has increased model availability (the cities tended to have about 20 EV models locally available over 2015) and provided relative certainty about vehicle deployment that local stakeholders can bank on. The major metropolitan areas in California had 3 to 13 times the average US electric vehicle uptake in 2015.
Local promotion activities are encouraging the electric vehicle market. The 30 cities in California with the highest electric vehicle uptake—with 8 to 25 times the US electric vehicle uptake—have seen the implementation of abundant, wide-ranging electric vehicle promotion programs involving parking, permitting, fleets, utilities, education, and workplace charging. These cities tend to be smaller, but Oakland and San Jose are also within the high electric vehicle uptake cities. There were twelve cities with electric vehicle market shares of new vehicles from 10% to 18% in 2015 including Berkeley, Manhattan Beach, and many throughout Silicon Valley.
The electric vehicle market grows with its charging infrastructure. The 30 California cities with the highest electric vehicle uptake have, on average, 5 times the public charging infrastructure per capita than the US average. In addition, workplace charging availability in the San Jose metropolitan area is far higher than elsewhere. Increasingly, major public electric power utilities and workplaces are expanding the public charging network to further address consumer confidence and convenience.
This analysis of the California market could have broader implications in defining best practice policies to support electric vehicles. Governments around the world are contemplating more progressive regulatory policies to promote electric vehicles. Policymakers are also investigating complementary local outreach, city policy, and charging infrastructure planning to pave the way for the emerging electric vehicle market. California provides a template for such state and local activities that reach more businesses and prospective consumers. The California experience suggests that if electric vehicle models are brought to more markets and there is supporting policy in place, market growth will continue. Our findings suggest that California’s playbook could be a helpful example to other regions seeking to encourage electric vehicle uptake.—Searle et al.