Assessment of Run-off-River Hydropower Potential in a Glacier-Fed Catchment Using a Glacio-Hydrological Degree-day Model: A Case Study of Budhigandaki River Basin, Nepal

Abstract

Assessment of hydropowerpotentialiscrucialwhichenableassociatedstakeholdersfor financial investments in future production of electricity. Discharge estimation plays a key role in assessing hydropowerpotential.Glacio-hydrologicalDegree-dayModel (GDM), which is widely acknowledged fully distributed model used to calculate discharge in glacierized river basins, including those with debris-coveredglaciers,andisnotedforitscomputational efficiency. This study aimed to assess run-off river hydropower potential using thismodel. The research was conducted in three stages,literaturereviewanddatapreparationinthefirstphase, modelcalibrationandvalidationinthesecondphaseand identifying possible hydropower sites, assessing their potential, and forecasting future discharge under the SSP2-4.5 and SSP5-8.5 scenarios in the third phases. The Budhigandaki River basin (BGRb) was chosen as a case study region in order to achieve the study's goal. The modeling period's NSE and VD values were 0.84 and -9.35%, respectively; the validation period's NSE and VD values were 0.86 and -8.62%. This suggests that the model is performing satisfactorily. From 2000 to 2015, this analysis found 35 possible locations with a combined capacity of 6,308 MW at a 40% flow exceedance. Additionally, the average increase in simulated discharge is 8.88% and 42.6%, respectively, according on the results of the future prediction of discharge and contribution of various components using two climatic scenarios, SSP2-4.5 and SSP5-8.5, for the period of 2020–2100. In the context of changing climatic condition, this study helps to fulfill the increasing demand for renewable energy and efficiently manage water resources.