Climate change and CCS increase the water vulnerability of China's thermoelectric power fleet

Large numbers of China's thermal power plants are in water-stressed regions. Changes in the availability of water resources due to climate change may impact the vulnerability of regional and national electricity generation. Here we explore this vulnerability for coal-fired power units (CPUs) as the generation-type most exposed to climate risk. We find many plants are already experiencing water scarcity and 120–176 GW of capacity will be exposed to water scarcity for at least one additional month per year in the 2030s. In the absence of carbon capture and storage (CCS) the national useable capacity of CPUs will increase slightly, mainly due to an increase in water availability for power plants in northern China under all climate scenarios except RCP8.5. However, CCS systems have been identified as essential in China's national roadmap for carbon neutrality and their use represents high water requirements. The addition of CCS significantly exacerbates water vulnerability, leading to further useable-capacity reductions of 7.4–7.7%. We assess several adaptations and find that early retirement of power plants is most effective, with interregional power transmission also playing an important mitigating role. Our work highlights the need for improved awareness of water resources in electricity planning.