User-driven potential for scalable, cost-effective, and flexible vehicle-to-grid resources in China

Vehicle-to-grid (V2G) technology is widely recognized for enhancing power system flexibility and supporting renewable energy integration. However, assessments of its cost effectiveness based on user willingness and its response capability under real-world conditions remain limited. This study evaluates the flexibility potential and economic performance of V2G in China by incorporating user preferences and regional heterogeneity. Using a discrete choice experiment (DCE) with 1,412 electric vehicle (EV) owners, we estimate user willingness to accept (WTA) and quantify V2G potential. Results show that V2G could provide up to 348 GW of flexibility, exceeding 11 times the current national energy storage capacity. Under emergency demand response scenarios, V2G is cost-competitive, with WTA around half that of conventional storage. However, WTA varies substantially ($0.14-$0.85 per kWh) and is sensitive to temperature, with winter conditions reducing participation by 21% and increasing costs by 17%. These findings highlight the need for behavior-aware policy and market design.