Abstract：
Hydropower plays a pivotal role in low-carbon electricity generation, yet many projects are situated in regions facing heightened water scarcity risks. This research devised a plant-level Hydropower Water Scarcity Index (HWSI), derived from the ratio of water demand for electricity generation to basin-scale available runoff water. We assessed the water scarcity of 1736 hydropower plants in China for the baseline year 2018 and projected into the future from 2025 to 2060. The results indicate a notable increase in hydropower generation facing moderate to severe water scarcity (HWSI >0.05), rising from 10% in 2018 to 24-34% of the national total (430-630 TWh), with a projected peak in the 2030s-2040s under the most pessimistic scenarios. Hotspots of risk are situated in the southwest and northern regions, primarily driven by decreased river basin runoff and intensified sectoral water use, rather than by hydropower demand expansion. Comparative analysis of four adaptation strategies revealed that sectoral water savings and enhancing power generation efficiency are the most effective, potentially mitigating a high of 16% of hydropower risks in China. This study provides insights for formulating region-specific adaptation strategies and assessing energy-water security in the face of evolving environmental and societal challenges.
摘要：
水电在低碳发电中发挥着举足轻重的作用,然而，许多项目位于面临严重缺水风险的地区。本研究设计了厂级水电水资源短缺指数(HWSI)，从发电需水量与流域规模可用径流水的比率得出。我们评估了2018年基准年中国1736个水电站的水资源短缺情况，并预测了2025年至2060年的未来。结果表明，面临中度至重度缺水（HWSI>0.05）的水力发电显着增加，从2018年的10%上升到全国总量的24-34%(430-630TWh)，在最悲观的情况下，预计在2030-2040年代达到峰值。风险热点位于西南和北部地区，主要是由于流域径流减少和部门用水加剧，而不是靠水电需求扩张。对四种适应策略的比较分析显示，部门节水和提高发电效率是最有效的，有可能减轻中国16%的水电风险。这项研究为面对不断变化的环境和社会挑战制定特定区域的适应战略和评估能源水安全提供了见解。
