EV Penetration's Double-Edged Sword: How Rapid EV Adoption Intensifies Traffic Congestion in China?

• In Event: Double-Edged Swords? Trying to Decrease Carbon from Transportation

Abstract

Carbon emissions from the transportation sector account for approximately 12% of total emissions in China. The rapid adoption of electric vehicles (EVs) has been widely celebrated for its potential to reduce carbon emissions (Richardson, 2013) and combat air pollution (Ji et al., 2012; Schnell et al., 2021). To support this transition, the Chinese government has introduced a series of policies to promote the widespread adoption of electric vehicles. The growing popularity of EVs has been facilitating China’s “dual carbon goals”. However, transportation electrification also presents challenges, such as traffic congestion. This study investigates the impact and mechanisms of EV adoption on traffic congestion across 100 major cities in China by using EV sales data from the Department of Motor Vehicles (DMV) and traffic jam related indices from Gaode. By analyzing monthly data from 2015 to 2023, with 9,306 observations, our empirical analysis reveals that a 1% increase in the EV adoption rate can significantly increase travel time on the same road section by 0.95%. By examining traffic data, accident reports, and ride-hailing operational patterns in major Chinese cities, this research identifies two critical mechanisms driving congestion: the surge in EV-dominated ride-hailing fleets and the rising incidence of traffic accidents linked to EVs. Given that EVs are predominantly adopted in ride-hailing services, our research finds that the popularity of these services can significantly worsen traffic conditions. Since ride-hailing electric vehicles have lower operating costs, their operating hours are generally longer than those of non-EVs. Our research also indicates that EV adoption can increase traffic litigation cases. The lower price of EVs compared to traditional combustion engine vehicles has attracted many first-time car buyers, resulting in a higher proportion of novice drivers among EV users than those with fuel vehicles. Due to novice drivers’ lack of driving experience, the probability of traffic accidents has increased, reducing road capacity, and thus causing traffic congestion. The accelerated penetration of EVs, particularly in ride-hailing services, has inadvertently intensified traffic congestion, undermining the environmental benefits of transportation electrification. To further explore this impact, this research calculates the increase in carbon emissions caused by traffic jam. Considering the effect of traffic congestion, longer travel times can somewhat undermine the benefits of electrification. According to the average penetration rate and some basic assumptions, this research estimates the percentage increase in carbon emissions due to traffic congestion. These findings underscore a critical policy dilemma: rapid EV proliferation and the changes in travel behavior caused by it, especially in ride-hailing, risks increasing electricity consumption by EVs and exhaust emissions from non-electric vehicles, further increasing carbon emissions and causing air pollution, thereby weakening the benefits of EV penetration. To mitigate this, the study advocates for integrated strategies, including dynamically improving road infrastructure, developing public transportation, and implementing stricter traffic management for EVs. Without such measures, the pressure of traffic congestion may slow down progress towards carbon neutrality. This study enhances the theoretical framework concerning the causes of traffic congestion from EV perspective and provides theoretical support for building a sustainable transportation system.

Authors

• Chengze Lu, The Hong Kong University of Science and Technology (Guangzhou)
  Presenting Author

• Zhengsheng YU, Hong Kong University of Science and Technology (Guangzhou)
  Non-Presenting Co-Author

• Tianle Liu, Harbin Institute of Technology (Shenzhen)
  Non-Presenting Co-Author