Work

Assessing hydropower production potential with multisite hydrological modeling in the Koshi river Basin, Nepal

Year: 2025

Type: article

Abstract: Hydropower is one of the major sources of energy for the Himalayan country Nepal which has abundant water resources. Several hydropower projects are being constructed and planned which envisage to meet the present and future energy demand, however, their production behavior under future climate conditions is not sufficiently documented. The Koshi River Basin (KRB) is located in eastern Nepal which is one of the hotspots for hydropower development and is particularly sensitive to climatic fluctuations in river discharge. To evaluate the potential impact of climate variations on river discharge and corresponding hydropower generation in KRB, a multi-site Soil and Water Assessment Tool (SWAT) model was applied in this study. The model was calibrated and validated for 1991–2009 and driven by downscaled CMIP6 climate projections (SSP2-4.5 and SSP5-8.5) for the future period 2031–2060, to simulate future discharge and hydro energy production. Results indicate that baseline energy production was projected to increase modestly under future scenarios, while adopting a Modified Design Discharge (MDD) could substantially enhance generation. Specifically, increases of 35–45% under SSP2-4.5 and 25–30% under SSP5-8.5 are identified from two independent CMIP6 GCM projections, highlighting additional hydrological opportunities beyond those achievable with conventional baseline discharges. These findings indicate additional hydrological opportunities but also emphasize that static design assumptions underestimate future variability. Adaptive discharge strategies, such as MDD, provide actionable guidance for aligning hydropower planning and infrastructure design with projected climatic variability, thereby strengthening long-term energy security and resilience in vulnerable mountain basins.

Source: Energy Conversion and Management X

DOI: 10.1016/j.ecmx.2025.101283

Authors: Aditya Nath Jha, Utsav Bhattarai, Manoj Lamichhane, Sushant Mehan, Sanyam Ghimire, Pawan Kumar Bhattarai