Underground Energy Storage for Compressed Air Energy Systems: A Review of Technologies, Challenges, and Prospects

Energy storage, as a core technology of the energy revolution, plays a critical role in promoting the development of new energy and achieving the “dual carbon” goals. Compressed air energy storage (CAES), as an emerging storage technology, has become an effective approach to advancing low-carbon and clean energy utilization due to its unique advantages. Underground CAES, characterized by large storage capacity and long service life, has become a key option for the development of this technology. However, its development still faces numerous unresolved risks and challenges. This paper primarily discusses underground reservoirs in the context of CAES, focusing on different types of underground storage and the associated risks and challenges. It analyzes various factors influencing the development of underground reservoirs and summarizes the specific impacts. The study concludes that addressing reservoir stability and sealing integrity is crucial for the advancement of underground CAES. Furthermore, it provides a prospective outlook on the future development of underground CAES, aiming to contribute to its sustainable progress.