Limitations and suggestions of electric transit charge scheduling

Abstract

A major factor hindering the popularization of electric buses (EBs) in the current automotive market is the high ownership cost of batteries and its significant upfront investment. For the daily maintenance of electric fleets, the amortized battery replacement cost is at least six times the charging cost. Thus, ensuring the healthy operation of the battery and prolonging the cycle life are some of the most concerned issues of the bus operators. In order to achieve the best operating mode, the operators are required to formulate an effective charging schedule with minimized battery wear. However, little quantitative formulation exists in prior literature to consider battery wear in bus charge scheduling. In this paper, a general formula is presented for battery wear cost consideration in charge scheduling based on the emerging literature. Then, the existing charge scheduling model is improved based on the proposed approach. A case study illustrates the significant difference in operating costs between charging plans developed with or without consideration of battery wear. The focus of this commentary is to present the crucial factors to improve the efficiency of EB operations and help make the charge scheduling models more realistic.