Analysis and Modelling of Cost-Sharing for Remedial Actions in Internationally Coordinated Congestion Management

This paper proposes a modelling framework for analysing cost sharing of RAs under internationally coordinated CM, with a particular focus on a pollution-based cost sharing algorithm. CM is simulated using a linear security-constrained optimal power flow (SCOPF) formulation under purely national and fully international coordination. For ex-post cost allocation, three methods are implemented and compared: location-based, congestion-based, and a pollution-based approach. The pollution-based algorithm constitutes the core contribution of the paper and allocates CM costs according to causal responsibility through a two-stage mapping process, linking RA activation to congested transmission lines and subsequently assigning costs to areas based on a PTDF-based power flow decomposition.

The framework is applied to a synthetic multi-area transmission grid model with hourly resolution over one year. Results show that international coordination reduces redispatch volumes and total CM costs, while simplified cost sharing methods lead to substantially different cost allocations compared to the pollution-based approach. The results highlight the importance of causally consistent, pollution-based cost sharing for internationally coordinated congestion management.