A regional-scale framework for assessing sustainable hydropower potential based on open-access data: the case of Central Asia

Central Asia is experiencing increasing energy demand, which is intended to be met through the development of renewable energy sources, including expanded hydropower generation. Yet no comprehensive, high-resolution regional assessment of remaining sustainable hydropower potential exists to date. This study fills that gap by developing an open-access, reproducible geospatial framework. In a step-wise approach, the theoretical, technical, and exploitable hydropower potential is estimated, ultimately deriving the remaining sustainable potential. River networks were delineated from a digital elevation model, and discharge estimates from a global hydrological model were combined with regional gauging data. The analysis incorporates efficiency losses, site-specific spill rates, exploitability constraints, and currently operating hydropower plants. Finally, geophysical hazards and detailed ecological criteria, including threatened species, protected areas, free-flowing rivers, and rare river types, were integrated. The theoretical potential amounts to 703 TWh yr−1, but successive reductions toward sustainable potential lower this value to 92 TWh yr−1. More than 80% of this remaining sustainable potential is concentrated in Tajikistan (43.7 TWh yr−1) and Kyrgyzstan (28.7 TWh yr−1). Uzbekistan (10.8 TWh yr−1) and Kazakhstan (8.4 TWh yr−1) hold smaller shares, Turkmenistan nearly none (0.01 TWh yr−1). The resulting high-resolution map can support both regional-scale strategic planning and site-specific feasibility analyses. By identifying where hydropower development is feasible and environmentally compatible, this study provides a robust foundation for sustainable hydropower expansion within Central Asia's Water-Energy-Food-Ecosystem Nexus.