Analyzing the Impact of Streamflow Drought on Hydroelectricity Production: A Global‐Scale Study

Electricity production by hydropower is negatively affected by drought. To understand and quantify risks of less than normal streamflow for hydroelectricity production (HP) at the global scale, we developed an HP model that simulates time series of monthly HP worldwide and thus enables analyzing the impact of drought on HP. The HP model is based on a new global hydropower database (GHD), containing 8,716 geo‐localized plant records, and on monthly streamflow values computed by the global hydrological model WaterGAP with a spatial resolution of 0.5°. The GHD includes 44 attributes and covers 91.8% of the globally installed capacity. The HP model can reproduce HP trends, seasonality, and interannual variability that was caused by both (de)commissioning of hydropower plants and hydrological variability. It can also simulate streamflow drought and its impact on HP reasonably well. Global risk maps of HP reduction were generated for both 0.5° grid cells and countries, revealing that 67 out of the 134 countries with hydropower suffer, in 1 out of 10 years, from a reduction of more than 20% of mean annual HP and 18 countries from a reduction of more than 40%. The developed HP model enables advanced assessments of drought impacts on hydroelectricity at national to international levels.Key Points: A new global hydropower database and a hydroelectricity production model were developed and validated The model simulates the impact of streamflow drought on monthly hydroelectricity production worldwide The 1‐in‐10 year risk of hydroelectricity production reduction due to drought is assessed at both 0.5° grid cell and country levelsBundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347MOST, National Key Research and Development Program of China (973 Program) http://dx.doi.org/10.13039/501100012166National Natural Science Foundation of China (NSFC) http://dx.doi.org/10.13039/50110000180