Impacts of climate change on the hydropower potential of a multipurpose storage system project in Bolivian Andes

Abstract

Andean Region, Bolivia. Rositas is a multipurpose storage system designed to enhance hydropower generation, agricultural production, and flood mitigation downstream in the Rio Grande basin. This study evaluates the climate resilience of the project by analysing changes in its hydropower potential. Using regional climate models from the Coordinated Regional Climate Downscaling Experiment (CORDEX) for the near (2040–2069) and far (2070–2099) future, river flow impacts were analysed under three future scenarios (RCP 2.6, 4.5, 8.5). K-means clustering was applied to 101 stations with similar climatic features to perform statistical downscaling (quantile perturbation, and delta change) at the catchment scale. The hydrological models SWAT+ and HEC-HMS were used to estimate changes in water availability and hydropower potential. Projections indicate that river discharges will increase in the wet season and decrease in the dry season, exacerbating severity of droughts. While annual hydropower potential increases by up to 11 % in the near future and 9 % for the far future, seasonal variations are significant. Energy potential decreases by up to 30 % in June to September but increases by up to 25 % in November to February. Calibration focused on seasonal transitions enhances analysis, since hydrological models significantly contribute to uncertainty. These results highlight climate risks faced by the Rositas project and the need for adaptative water management strategies to mitigate potential water conflicts. • Climate change impacts water availability and hydropower potential. • K-means clustering identified climate patterns. • Statistical downscaling was applied to an ensemble of six RCMs. • Model calibration should focus more on seasonal transitions. • Dry season hydropower potential is projected to decrease in the Rositas project.