Optimal mixed charging schemes for traffic congestion management with subsidy to new energy vehicle users

Abstract Traffic congestion and emissions are two severe and urgent problems in the transportation field. To alleviate congestion and encourage green travel, this paper studies a mixed charging scheme for the multimodal transportation network including conventional vehicles (CV) and new energy vehicles (NEV). We exploit the optimal mixed charging schemes according to the mixed equilibria and system optimum model. The mixed equilibria characterized by the variational inequality system represents that the players follow either the user equilibrium or Cournot–Nash equilibrium principle in routing choice. The proposed mixed scheme comprises a regular tolling plan and a tradable credit plan for the CV and NEV users, respectively, where the tradable credits can be seen as a subsidy to the NEV users since they are issued free by the government. Moreover, the existence of the optimal mixed charging scheme is proved for the multimodal transportation network and demonstrated numerically by a concrete example.