The Value of Battery Hybridization for Small Hydropower Plants: A Sensitivity Analysis on Plant Design

Abstract

This paper presents a techno-economic assessment of battery hybridization for small run-of-river hydropower based on a 5 MW Francis turbine with a 150 m head. A deterministic Mixed Integer Linear Programming (MILP) framework is used to compare four operating configurations: standalone battery, standalone turbine, weakly coupled hybrid (turbine and battery optimized separately, the primary benefit being reduced network taxes), and strongly coupled hybrid using the XOR algorithm patented by Supergrid Institute. Revenue maximization covers the day-ahead, FCR and aFRR markets (capacity and energy) using 2025 French market prices. A sensitivity analysis is conducted across three hydrological scenarios (dry, average, wet) and three upstream reservoir capacities (0 hours, 2 hours and 24 hours of full-power generation). Results show that advanced hybridization only delivers significant additional value when the hydraulic plant includes upstream storage capacity. Without a reservoir, gains are negligible. Larger reservoirs amplify hybridization benefits, although the associated civil engineering costs may not be economically justified unless the reservoir already exists. Hydrology affects absolute revenues but does not significantly alter the relative gains brought by hybridization.

F, Grand-Perret; Quentin BOUCHER, Camille PRUD’HOMME, Guillaume AMADEO