A Market-Driven Approach to Congestion Management: Leveraging Cross-Grid Flexibility in Distribution Networks

The rapid integration of renewable energy sources and the electrification of key sectors have significantly increased congestion challenges in power distribution networks. Traditional grid reinforcement strategies are often costly and time-consuming, necessitating the adoption of more flexible, market-based solutions. This paper introduces the OpenFlex market, a novel local flexibility market structure designed to enhance congestion management by incorporating cross-grid flexibility resources. The proposed framework enables Distribution System Operators (DSOs) to procure flexibility services beyond their local network, improving cost efficiency and system resilience. By leveraging the Inter-Grid Load Transfer Coordinator (IGLTC), the model facilitates optimal load transfers, minimises network losses, and enhances voltage stability. A case study demonstrates the effectiveness of the framework under various operational scenarios, highlighting its potential for reducing congestion management costs while ensuring grid reliability. Although DSO-level local flexibility markets are still at the pilot stage, the proposed framework extends these concepts by enabling cross-grid flexibility trading and coordinated congestion management, aligning with emerging regulatory trends. The results underscore the importance of regulatory support for cross-grid flexibility integration and suggest future directions for real-time flexibility trading and digital optimisation techniques.