An overview of hydrogen underground storage technology and prospects in China

• Elaborate ways and mechanisms of hydrogen underground storage.
• Explain the feasibility and the requirements of hydrogen underground storage.
• Elaborate the barriers and prospects of UHS development in China.

Renewable energy is playing more and more important roles nowadays in the world and hydrogen is considered as one of them with high availability, and being clean. This paper firstly begins with the utilization and development of hydrogen as energy, explains the significance of underground hydrogen storage and conventional storage methods, summarizes the underground gas storage experience of all countries, and concludes the general patterns of underground gas storage, for example, depleted reservoirs, aquifers, salt caverns and excavated caverns. After that by comparing the physical and chemical properties of hydrogen and methane, the feasibility of underground hydrogen storage has been analyzed in depth and the potential barriers, such as high permeability, chemical reaction, extraction purity, are summarized. Finally the development prospects of hydrogen underground storage in China are summed up in the perspectives of energy restructure, policy support, and technology development.