Item

Abstract

Hydrogen stands out as a promising energy carrier, particularly when produced from renewable sources. Underground hydrogen storage (UHS) in geological formations offers a viable solution for large-scale hydrogen storage. This study presents numerical simulations of cyclic hydrogen storage within an anticline structure of a deep saline aquifer at the Ketzin site, as part of the preparatory research for a potential UHS demonstrator in the North German Basin, Germany. The effects of well trajectory are evaluated by comparing vertical and deviated wells and varying perforated well lengths. The gas distribution in the reservoir as well as the recovery efficiency and production purity are significantly influenced by the perforated length and well trajectory. The results indicate that deviated wells offer higher volumes of stored gas and lower brine production at the same pressure limits. Additionally, it is examined how the fault transmissibility, of existing vertical fault structures influences the storage performance of a vertical well. It is found that permeable faults enhance injection and production volumes while closed faults offer better long-term gas containment and withdrawal productivity. By investigating well design and fault characteristics, this study addresses two critical aspects of UHS performance within realistic heterogeneous geological reservoir models that have been underexplored in the existing literature. The findings provide novel insights into the dynamics of hydrogen storage under diverse realistic scenarios and demonstrate the viability of UHS at the Ketzin site as a numerical proof-of-concept. These results contribute valuable guidance for optimizing site selection and storage design in future UHS projects.