Building confidence in simulation of underground hydrogen storage: recent advancements and remaining gaps

Underground hydrogen storage (UHS) for energy supply-demand management is a relatively new topic compared to the natural gas storage. It is gaining increasing interests due to the ‘hope’ that hydrogen may indeed be the missing link of scalable low-carbon energy systems. Successful deployment of UHS depends on reliable performance analyses, which depend on rigorous understanding of the relevant cyclic processes at various scales. Beyond this, geophysical field and lab data sets, collected on different scales, need to be conveniently utilized and integrated in the dynamic simulations in order to construct the multiscale models and calibrate their many parameters. Furthermore, simulations are often performed on highly heterogeneous upscaled reservoir models which raise the question of how reliable our predictions for the uncertain systems can be.

To address this challenge, in this invited talk, a multiscale experimental-numerical framework for rapid site selection and performance analyses of UHS is presented. The framework addresses the thermo-chemical properties at molecular scale, trapping and transport mechanisms at micro-meter scale, and the system performance at continuum reservoir scale. The nonlinear, time-dependent mechanical response of the host rocks is also analysed, with the focus on model construction and parameter calibration, including field validation. Emphasizing the importance of reliable performance assessments under uncertainty, some key gaps in this evolving technology will be also addressed.