The storage of natural gas in underground geological formations (UGS) has been widely adopted to guarantee a real-time response to the market requests as well as to ensure National “strategic” reserves. In the recent past, the UGS and related technologies have been approached with increasing interest also in terms of CO2 sequestration and of large-scale storage of chemical energy, with the potentiality in playing a fundamental role in the energy transition process toward the de-carbonization goals. In the context of the gas storage, both current regulations and public concerns call for geomechanical analyses to assess the safety of the infrastructures and the underground system and the recently formalized Virtual Elements Method (VEM) has been showing promising results to address such issue. An extensive research project, involving multi-competences, dedicated to the implementation of a VEM code able to face the geomechanical aspects related to oil&gas fields is under development. The paper presents the VEM code simulation results of a realistic case study representing a typical gas field in the Italian Adriatic offshore subject to UGS. The effects of the production/injection operations, in terms of induced stress variations and consequent displacements, were calculated via the implemented VEM code and satisfactorily validated with the solution obtained from a FEM commercial software.

Keywords: Underground Gas Storage, Virtual Elements Method (VEM), Geomechanical Analysis, Numerical Simulation.