Bidirectional charging (V2G) is a promising source of distributed flexibility, but its realisable value depends not only on technical potential but also on participation behavior, local grid conditions and economic viability due to flexibility costs. Prior work has addressed this by integrating behavioural participation modelling with spatially implicit Urban Digital Twins, showing that heterogeneous contract acceptance strongly shapes available flexibility and grid impacts. This research project builds on this foundation and extends the modelling framework into a full process chain for assessing the technical and economic value of V2G. The approach introduces a grid-oriented flexibility optimization and cost evaluation layer.

Starting from a spatially implicit Urban Digital Twin, the participation based on a behaviour economic analysis and plug-in time series is derived. A hybrid simulation framework models charging and discharging strategies across heterogeneous user groups and operational settings. To minimize coincident peak load from electric vehicles, household demand, and heat pumps, a max-greedy optimization using a bisection procedure is applied to determine the maximum feasible load shifting and V2G contribution under technical and behavioural constraints.

The resulting peak reductions are translated into distribution grid impacts and monetized using network-related cost metrics, enabling a location-specific assessment of V2G value. Results show strong spatial and temporal heterogeneity: similar participation levels can lead to substantially different outcomes depending on user composition and availability patterns. In particular, the presence of non-commuter vehicles during morning hours is identified as a critical factor for mitigating heat-pump-driven peak loads.

The findings demonstrate that extending behaviourally grounded participation models with optimization-based flexibility activation and cost evaluation is essential for realistic V2G assessment. The proposed process chain enables consistent, location-specific evaluation of V2G strategies and supports the targeted deployment of bidirectional charging by jointly considering participation, technical feasibility, and economic impact.