Author(s): Marc-Antoine Courtois; Pedro Manso; Giovanni De Cesare; Vincent Dehail

Linked Author(s): Pedro Manso

Keywords: Storage hydropower plants; Hydropeaking mitigation; Compensation basin; Battery energy storage system (BESS)

Abstract: Hydropeaking caused by storage hydropower plants leads to abrupt variations in river discharge, which disrupt natural hydrological regimes and negatively impact aquatic ecosystems. In Switzerland, environmental regulations require mitigation measures to reduce these effects, typically through compensation basins. However, alternative solutions, such as integrating Battery Energy Storage Systems (BESS), offer innovative possibilities for hydropeaking mitigation. This study evaluates different scenarios combi ning storage hydropower plants with BESS, with or without compensation basins, to assess their feasibility and effectiveness in meeting environmental objectives. A 2D hydraulic model (HEC-RAS) was used to establish relationships between turbine discharge variations and river water level fluctuations. Based on these results, hydropeaking mitigation scenarios were defined and evaluated against key criteria: environmental performance, economic feasibility, operational flexibility, and water usage. The findings indicate that a hybrid operation of Francis turbines with BESS can significantly reduce the required volume of compensation basins, while a Pelton-BESS system without a basin approaches required environmental thresholds. Moreover, the lifetime of the BESS is directly influenced by its charge/discharge conditions, highlighting the importance of optimized operational strategies.

DOI: https://doi.org/10.64697/iahr.proc.ise2026.abs.231

Year: 2026