Assessing the Role of Electric Vehicle Availability in the Energy Management Problem

Abstract

The electrification of transportation introduces both opportunities and operational challenges for the power system, as electric vehicles (EVs) with unidirectional (V1G) and bidirectional (V2G) capabilities interact with variable renewable supply. This paper investigates the role of EV flexibility and availability on power system operation using projected 2030 data for the Republic of Ireland. The study examines four combined scenarios of solar generation and load levels (HPHD, HPLD, LPHD, LPLD) over a one-week period, alongside three EV availability cases, from fully available to daytime-restricted operation. A mixed-integer linear programming (MILP) model is used for the evaluation of operational costs and generation dispatch under varying EV participation and renewable conditions. Results indicate that limiting EV availability can increase total system costs by over 8% in the HPHD scenario, reducing EV participation by approximately 80%, while including EV discharging costs mitigates cost increases to 1.7–3% and lowers participation reductions. Furthermore, bidirectional V2G operation consistently outperforms unidirectional V1G charging, reducing operational costs by up to 6.4% and enhancing system flexibility. Sensitivity analyses highlight the strong dependence of operational benefits on both availability and economic assumptions. Overall, the findings demonstrate that EVs can significantly enhance optimal resource dispatch and system resilience, particularly under high renewable penetration, while emphasizing the importance of accurately modeling user behavior, connection patterns, and network integration for realistic power system planning.