Mitigation of congestion related to quick charging of electric vehicles based on waiting time and cost-benefit analyses: A japanese case study

Increased use of electric vehicles (EVs) has led to the demand for a larger number of quick-charging units (QCUs) and charging stations (CSs). Long charging queues (congestion) result in inconvenience and high social cost. In this study, QC service is modeled in terms of queueing, and the charging records of QCUs are analyzed to estimate future waiting times. Using these results, an analysis is conducted to determine how the installation of additional QCUs would reduce waiting times for charging. In addition, a cost-benefit analysis is performed on the installation of an additional QCU. To reveal the quick charging (QC) demand, 93,839 QC records in Japan are analyzed. As a result, the inter-arrival and charging times of QC demand can be represented as exponential and normal distributions, respectively. In addition, the expected waiting times for EV charging in the future are also calculated and applied to calculate the allowable waiting time and to perform cost-benefit analysis. Two different evaluations show that the demand criterion for installing an additional QCU is 10 +/- 3 vehicles per day per CS.