Development status and progress of pumped storage in underground space of closed/abandoned mines

Innovative approaches to the development of clean energy are seen as a significant driving force for achieving China’s “dual carbon” goals. To address the challenge of unstable electricity supply from large-scale renewable energy, the construction and development of pumped storage power plants have been promoted through the proposal and rapid growth of new power systems. However, some traditional pumped storage power plants have been constrained by factors such as ecological protection and terrain. On the other hand, a unique solution is provided by repurposing or closing abandoned mines. Due to their abundant water and space resources, closed/abandoned mines can be innovatively developed for pumped storage energy, thereby extending the economic lifespan of mining areas and reducing negative impacts on the environment and economy. The technological advancements and application progress of abandoned mine pumped storage energy technology, both domestically and internationally, are comprehensively reviewed in this study through literature analysis, aiming to establish suitable utilization models and management systems for abandoned mine pumped storage energy in line with China’s national conditions. Detailed explanations of the principles, classifications, advantages, and disadvantages of closed/abandoned mine pumped storage energy technology are provided. The utilization models of closed/abandoned mine pumped storage power stations are summarized, and the site selection factors are revised based on previous research. Additionally, the current research status of two-phase flow characteristics in pumped storage power stations, water pump-turbine operating conditions, stability of surrounding rock in underground spaces, and calculation of underground water storage space volume are reviewed. Key technical challenges that urgently need to be addressed, such as pump-turbine technology and control of underground space stability, are identified. Furthermore, an extensive literature review is conducted on the ecological and environmental protection, market demand and economic benefits, and policies and regulations related to closed/abandoned mine pumped storage. The development of closed/abandoned mine underground space pumped storage technology can provide some insights into the utilization of underground space resources in China and offer new pathways for ensuring national energy security and high-quality socio-economic development.