Abstract: Based on a systematic analysis of the technological evolution, policy implementation, and pricing mechanisms of vehicle-to-grid(V2G) technology, this study focuses on constructing a multi-dimensional value-stacked discharge pricing model and market mechanism to guide electric vehicles as flexible resources in participating in grid optimization. V2G development follows a three-stage path: unidirectional orderly charging, bidirectional V2G discharge, and participation in ancillary services. Its pricing mechanism evolves from government-set pricing to market-based pricing, and from simple price differentials to multi-dimensional value aggregation. Addressing Hunan Province's regional characteristics-predominantly hydroelectric power, pronounced summer-winter peak loads, and distribution network congestion in the Changsha-Zhuzhou-Xiangtan area,the study constructs a multidimensional pricing model accounting for time, space, and market structure. It quantitatively analyzes the fundamental discharge costs, grid value, and environmental benefits. The study proposes that Hunan could draw inspiration from California's real-time pricing and Germany's market coupling mechanisms. It recommends designing time-of-use seasonal pricing tailored to seasonal load patterns, piloting nodal pricing at load centers, and establishing a composite pricing mechanism incorporating green power consumption and carbon value. Ultimately, the scaled development of vehicle-grid interaction requires establishing sustainable business models through measures such as clarifying battery depreciation compensation, standardizing communication protocols, and lowering market barriers. This approach will provide low-cost flexibility support for the new power system.

Key words: vehicle-to-grid interaction, electric vehicles, business model, pricing mechanism, policy support