Empirical Analysis of Electric Vehicles’ Charging Patterns: Case Study From Shanghai

Abstract

Automotive electrification is a vital component of the carbon-neutrality agenda. To counter the influence of shrinking public incentives for purchasing electric vehicles (EVs), it is crucial to deepen the understanding of the existing users’ use cases and clear the barriers for potential EV owners in daily usage. To this end, our study analyzes an 11-month usage data from a large sample of EVs, including 3,777 battery EVs (BEVs) and 5,973 plug-in hybrid EVs (PHEVs) in Shanghai, China. Based on their daily travel intensity, the EVs are clustered into two groups used primarily for private and commercial purposes. Comprehensive analyses are then conducted for each group of EVs, with major findings retrieved as follows: 1) Similar to gasoline-car users, BEV users also tend to charge their vehicles when the SOC declines to a certain level; 2) Private BEVs use slow charging in 69% charging sessions, whereas commercial BEVs use fast charging dominantly for 89% occasions; 3) Replacing all the remaining gas-based passenger cars in Shanghai with BEVs will result in a 10-15% surge in charging load to the power grid; 4) In opposite to BEVs, PHEVs with small batteries are charged less often and rely more on gas power, whereas large-battery PHEVs are used like BEVs and charged more frequently; and 5) PHEVs' battery utilization can be significantly overestimated using the method proposed by the Society of Automotive Engineers, especially for the private sector. Potential EV-related policy implications are discussed based on the empirical findings.

Keywords: Electric vehicles, Charging activities, Charging facilities, Range anxiety, Energy consumption rate, Empirical analysis