From theoretical to sustainable potential for run-of-river hydropower development in the upper Indus basin

A comprehensive assessment of hydropower resource potential considering factors beyond technical and financial parameters is missing for the upper Indus basin (UIB). Our framework takes a systems approach to quantify the theoretical to sustainable hydropower potential by successively considering natural, technical, financial, anthropogenic, environmental, and geo-hazard risk constraints on hydropower at individual sites as well as at the basin-scale. Theoretical potential of the UIB is 1564 TWh/yr at 500-m resolution. Across three energy focus and three geo-hazard risk scenarios, our cost-minimization model finds that technical (12%–19%), financial (6%–17%) and sustainable (2%–10%) potential are a small portion of the theoretical value. Mixed development combining plants of various size, cost and configuration provides the highest potential with the best spatial coverage. Alongside, our review of 20 datasets reveals a visualized potential exceeding 300 TWh/yr from 447 hydropower plants across the UIB, with only a quarter of the potential materialized by mostly large plants in the mainstreams. Hydropower cost curves show that Swat and Kabul sub-basins have a larger proportion of cost-effective and sustainable potential untapped by the visualized potential. Water use for other sectors represents the strongest constraints, reducing a third of the technical potential when evaluating sustainable potential. Ultimately, human decisions regarding scale, configuration and sustainability have a larger influence on hydropower potential than model parameter assumptions. In quantifying hydropower potential under many policy scenarios, we demonstrate the need for defining hydropower sustainability from a basin-scale perspective towards energy justice and balanced fulfilment of Sustainable Development Goals for water and energy across the Indus.