Hydropower plays an important role as renewable and clean energy in the world's overall energy supply. Electricity generation from hydropower represented approximately 16.6% of the world's total electricity and 70% of all renewable electricity in 2015. Determining the different effects of 1.5°C and 2°C of global warming has become a hot spot in water resources research. However, there are still few studies on the impacts of different global warming levels on gross hydropower potential. This study used a coupled hydrological and techno‐economic model framework to assess hydropower production under global warming levels of 1.5°C and 2°C, while also considering gross hydropower potential, power consumption and economic factors. The results show that both global warming levels will have a positive impact on the hydropower production of a tropical island (Sumatra) relative to the historical period, however, the ratio of hydropower production versus power demand provided by 1.5°C of global warming is 40% higher than that provided by 2°C of global warming under RCP6.0. The power generation by hydropower plants shows incongruous changing trends with hydropower potential under the same global warming levels. This inconformity occurs because the optimal sites for hydropower plants were chosen by considering not only hydropower potential but also economic factors. In addition, the reduction in CO2 emissions under global warming of 1.5°C (39.06×106 t) is greater than that under global warming of 2°C (10.20×106 t), which reveals that global warming decreases the benefits necessary to relieve global warming levels. However, the hydropower generation and the reduction in CO2 emissions will be far less than the energy demand when protected areas are excluded as potential sites for hydropower plants, with a sharp decrease of 40‐80%. Thus, government policy‐makers should consider the tradeoff between hydropower generation and forest coverage area in nationally determined contributions.

中文翻译：

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水电生产从 1.5°C 比 2°C 气候情景中受益更多

水电作为可再生清洁能源，在世界整体能源供应中发挥着重要作用。2015 年，水力发电约占世界总发电量的 16.6% 和所有可再生电力的 70%。确定全球变暖 1.5°C 和 2°C 的不同影响已成为水资源研究的热点。然而，关于不同全球变暖水平对总水电潜力的影响的研究仍然很少。本研究使用耦合的水文和技术经济模型框架来评估全球变暖水平为 1.5°C 和 2°C 下的水电生产，同时还考虑了总水电潜力、电力消耗和经济因素。结果表明，相对于历史时期，两个全球变暖水平都会对热带岛屿（苏门答腊）的水电生产产生积极影响，然而，全球变暖 1.5°C 提供的水电生产与电力需求之比为 40 % 高于 RCP6.0 下全球升温 2°C 所提供的值。在全球变暖水平相同的情况下，水力发电厂的发电量与水电潜力呈现出不协调的变化趋势。这种不一致的发生是因为水电站的最佳选址不仅考虑了水电潜力，还考虑了经济因素。此外，全球升温1.5°C（39.06×106 t）下CO2排放量的减少量大于全球升温2°C（10.20×106 t）下的CO2排放量，这表明全球变暖减少了缓解全球变暖水平所需的好处。但是，如果将保护区排除为水力发电厂的潜在地点，水力发电和二氧化碳排放量的减少将远低于能源需求，急剧下降 40-80%。因此，政府决策者应在国家自主贡献中考虑水力发电和森林覆盖面积之间的权衡。