Impact of battery storage on congestion management in the CWE region

Details

Supervisors

Lété, Quentin

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil en génie de l'énergie , à finalité spécialisée

Abstract

The rapid expansion of variable renewable generation across Central Western Europe (CWE) is intensifying intra-zonal transmission congestion and the associated re-dispatch costs borne by transmission system operators (TSOs). Battery energy storage systems (BESS) are increasingly deployed as a flexibility resource, yet their net impact on physical network congestion remains poorly understood. This thesis investigates whether price-arbitrage BESS deployment in Belgium increases or decreases intra-zonal re-dispatch costs, and how this effect evolves as installed capacity scales from 800 MW to 6,000 MW. A two-stage simulation framework is developed, combining a flow-based zonal pricing model with a nodal DC optimal power flow (DCOPF) re-dispatch model applied to the full CWE network. Two generation datasets are considered: a 2018 thermal-dominated baseline and an updated 2025 dataset reflecting Belgium's partial nuclear phase-out, the retirement of French and Dutch coal capacity, and the substantial expansion of solar and wind generation across the region. Two re-dispatch methods define the range of options for cross-border coordination among TSOs. Results show that battery deployment consistently increases Belgian re-dispatch costs under both methods and both datasets, as price-arbitrage dispatch creates injection patterns that aggravate existing corridor overloads. However, the net economic balance (zonal generation cost savings minus the incremental re-dispatch cost) remains robustly positive and grows with capacity, reaching 35.1 M€/year in 2018 and 68.2 M€/year in 2025 at 6,000 MW. The 2025 high-renewable context amplifies both the arbitrage value, driven by the solar duck curve, and the re-dispatch impact, while inverting the sign of Belgium's cost allocation under full EU-wide TSO coordination. These findings suggest that the economic benefits of large-scale Belgian BESS will strengthen with the energy transition, but that realising the full benefit requires closer alignment between battery dispatch and transmission system operation.