Session 6. Oral Presentation for: Assessing geomechanical risks for a potential underground hydrogen storage project using 3D geomechanics – a first in Australia

Presented on 19 May 2026: Session 6 Lochard Energy’s H2RESTORE project, supported by the Australian Renewable Energy Agency through their Advancing Renewables Program, aims to establish the technical feasibility and commercial potential for the storage of hydrogen (H2) in existing depleted gas reservoirs. This paper presents Australia’s first field-scale geomechanics study that incorporates laboratory-observed H2-related changes in rock mechanical properties into coupled 3D geomechanics simulations for a potential underground H2 storage site in Victoria. The paper provides an applied case study that demonstrates how H2-induced changes in rock mechanical behaviour can be incorporated into an integrated geomechanical modelling framework to support early-stage assessment. The work includes construction and calibration of 1D Mechanical Earth Models and a coupled 3D geomechanical model. Static reservoir characterisation was used as input to construct the 3D geomechanical model, while dynamic simulation of H2 storage cycling was used to inform the time-varying pressure and H2 molar fraction for the coupled 3D simulations. Laboratory measurements from CSIRO were translated into formation-specific adjustments to understand the impact of H2 exposure on geomechanical properties. The results enabled geomechanical risks assessment. Surface deformation was in millimetres, with H2 weakening potentially increasing deformation by up to 1.5 times. The cap rock maintained integrity throughout H2 storage cycles. Although fault plastic strain slightly increased at the fault nearest the well due to H2 exposure, it was not enough to change the overall risk profile. The workflow offers a practical and adaptable approach that operators can apply when assessing geomechanical risks, establishing the operational pressure envelope, and developing measurement and monitoring programs for H2 storage operations. To access the Oral Presentation click ‘Supplementary data’ below. To read the full paper click here