Multi-Objective Optimization of On-Grid Park and Ride EV Parking Station With Renewable Energy

In response to the growing need to reduce greenhouse gas emissions and achieve a decarbonized society, this study focuses on the optimal design of electric vehicle (EV) charging stations powered by renewable energy sources. Battery electric vehicles (BEVs), which emit no CO2 during operation, are particularly effective when combined with Park and Ride (P&R) systems that mitigate urban traffic congestion. This paper investigates the optimal operation and configuration of P&R BEV charging stations in Okinawa, Japan, comparing two power supply methods: on-grid and off-grid systems using photovoltaic (PV), wind power generation (WG), and battery energy storage systems (BESS). A multi-objective optimization model is developed to minimize the annual operating cost while meeting EV charging demand. To identify the optimal configuration, an exhaustive search of equipment unit combinations is conducted. The resulting pareto front reveals trade-offs between total annual EV charging energy and parking operator profit. In addition, three representative charging levels are analyzed in detail. Results show that on-grid systems achieve higher profit margins under moderate charging demand, leveraging grid power to maintain stable operations. In contrast, off-grid systems, while requiring higher initial investment, exhibit greater self-sufficiency and perform better in high demand scenarios or in remote areas with limited grid access. Thus, the optimal power supply method should be selected based on site-specific conditions, such as EV charging scale, regional infrastructure, and resilience requirements. Among the options, the on-grid system is identified as the most practical and economically viable solution under current technological and institutional conditions.