Electrified Transportation System Performance: Conventional Versus Online Electric Vehicles

Abstract

In recent years, the electrification of ground transportation has emerged as a trend to support energy efficiency and CO2 emissions reduction targets. The true success, however, of this trend depends on the successful integration of electric vehicles into the infrastructure systems that support them. Left unmanaged, conventional electric vehicles may suffer from delays due to charging or cause destabilizing charging loads on the electrical grid. Online electric vehicles have emerged to remediate the need for stationary charging and its effects. This chapter seeks to objectively compare the systemic impacts of these two electric vehicle concepts on the combined electrical power grid and road transportation system. It applies a recently developed hybrid dynamic system model of the transportation-electricity nexus that holistically incorporates vehicle dispatch, route choice, charging station queues, coordinated charging, and vehicle-to-grid stabilization. It draws upon Axiomatic Design for Large Flexible Engineering System Theory to superimpose a marked petri net model layer on a continuous-time kinematic and electrical state evolution. The results show that online electric vehicles, unlike their conventional vehicle counterparts, are able to avoid charging station queues and thus are able to meet the needs of a greater variety of transportation uses cases including commercial and public fleets. Their impacts on the power system also differ. While conventional electric vehicles are likely to require greater investment to expand power system generation capacity, online electric vehicles are likely to incur greater operating costs to manage their charging loads. The chapter concludes with several directions for future work in the development of intelligent transportation-energy systems which can serve to reduce both costs for both vehicle concepts.