Parking-and-Charging-as-a-Service: Online admission and allocation policies for an integrated parking and charging reservation system

With a substantial increase in public charging facilities globally, the world has witnessed a significant surge in support for electric vehicles (EVs), making them more accessible and sustainable. However, EV drivers still struggle to find available charging spaces, which are often occupied by non-charging vehicles. While prohibiting parking in charging spaces can mitigate this issue, it can lead to underutilization of charging spaces when charging demand is low but parking demand is high. Existing studies often treat parking and charging management as separate issues, overlooking the fact that most charging spaces are located in parking facilities and jointly operated with parking spaces to serve both parking and charging needs. In this context, coordinated management of parking and charging spaces is essential for improving operational efficiency. This paper proposes an integrated Parking-and-Charging-as-a-Service (PCaaS) reservation system that jointly manages parking and charging demand through admission and allocation controls. Specifically, users submit parking and charging requests in advance, and the system dynamically determines whether to accept each request and, if accepted, allocates a parking or charging space accordingly. We model this sequential decision-making problem as a Markov decision process. Since deriving the optimal policy is computationally intractable, we introduce a bid price control policy to guide request admission and space allocation. Two decomposition methods are developed to compute bid prices efficiently. Using real-world parking facility data, we evaluate the performance of the proposed policies across varying problem scales, levels of dynamism, demand scenarios, and parking facility configurations. The results demonstrate that the proposed policies substantially enhance overall revenue and capacity utilization compared to current practices. The insights gained provide guidance for the planning and operation of public parking facilities.