China proposed the goal of carbon peak by 2030 and carbon neutrality by 2060 at the 75th session of the United Nations General Assembly. Accelerating the development of clean energy is the key to achieve this carbon peak and neutrality goal. However, large-scale grid connection of new energy brings great challenges to the stable and safe operation of power grid. As a regulating power source and energy storage power source, pumped hydro energy stora. China proposed the goal of carbon peak by 2030 and carbon neutrality by 2060 at the 75th session of the United Nations General Assembly. Accelerating the development of clean energy is the key to achieve this carbon peak and neutrality goal. However, large-scale grid connection of new energy brings great challenges to the stable and safe operation of power grid. As a regulating power source and energy storage power source, pumped hydro energy storage (PHES) has strong regulating ability and is characterized as a reliable operation with broad prospects for development. However, the current field-survey-based method of site selection for PHES is time consuming, labour intensive, and costly. Improper site selection would cause ecological environment damages among other problems. A scheme or protocol that enables the automated site selection of PHES is therefore urgently required. The objective of this study was therefore to develop a new tool based on digital elevation model (DEM) and geographic information system (GIS) hydrological analysis function to screen out the potential PHES sites. ArcGIS, as a leading geospatial software, provides a set of geoprocessing (GP) tools for raster analysis. ArcPy is a Python package that runs in the ArcGIS environment. It can quickly invoke existing tools in ArcGIS to create custom extension modules. In this study, ArcPy was used to screen the site of PHES based on reservoir capacity and dam height, etc. Taking the southern Shaanxi Province, China as an example, comprehen. Digital elevation modelGeographic information systemCarbon neutralCarbon peakPumped hydro energy storageComprehensive evaluationAHPAnalytic Hierarchy ProcessCO2Carbon DioxideCRITICCriteria Importance Though Intercrieria CorrelationCSIComprehensive Suitability TndexDEMDigital Elevation ModelGISIn October 2020, China set the goal of peaking CO2 emissions by 2030 and neutralizing CO2 emissions by 2060. The application of renewable or clean energy has become an important way of energy conservation and emission reduction in the context of global low-carbon economy, especially under the goal of "carbon neutrality" and "carbon peak". The major clean energy sources include wind power, solar power, nuclear power and hydropower. In 2020, the global installed hydropower capacity was 1330 GW, accounting for more than 54% of the world's renewable energy generation capacity, making it the most widely available renewable energy source. Solar and wind power are fluctuated and intermitted in utilization due to the weather conditions [,, ], which brings great challenges to maintain real-time balance, safety, and stability of power system. Nuclear power may increase peak-valley difference, leading to insufficient utilization of electricity as well as difficulties in achieving large-scale optimal allocation of power resources. Hydropower is not only a renewable energy with the highest efficiency and best performance, but also an important guarantee for large-scale grid access of intermittent energy [8,9]. At present, large capacity energy storage has been recognized as an important method to reduce fossil fuel demand and environmental degradation [10,11], while pumped hydro energy storage (PHES) is one of the most natural, mature, and practical way of large-scale storage energies in the. 2.1. PHES and its potential for China power supplyPHESs (Fig. 1) are special hydroelectric plants that use electricity to pump water into the upper reservoir when energy demand is low and release water back into the lower reservoir when energy demand is high.Fig. 1. Schematic of pumped hydro energy storage (PHES).According to the statistical results of Han et al., 2021 has seen the largest number of new construction points and the largest installed capacity of PHESs over past years. In 2021, some PHESs, such as Fengning in Hebei, Yimeng in Shandong, Jixi in Anhui, Meizhou in Guangdong and Zhouning in Fujian, were put into operation, with an additional installed capacity of 4.9 GW. Newly approved pumped storage projects such as Taishun and Tiantai in Zhejiang, Nanning in Guangxi and Zhuanghe in Liaoning, with an approved installed capacity of 13.7 GW. At the same time, more than 200 GW PHESs carried out preliminary survey and design work, and 48 projects are under construction with an installed capacity of 61.53 GW. Both the capacities of PHESs built and under construction in China are the largest in the world.Although PHES has been booming in China, its proportion in total power installation is significantly lower than that in developed countries such as European countries and the United States. Therefore, China should speed up the large-scale construction of PHES. Considering the further growth o.
