Hadi Hajibeygi 

Delft University of Technology

Underground hydrogen storage: a multiscale numerical-experimental study

Underground Hydrogen Storage (UHS) is a crucial component of the future green energy mix, allowing to store energy in the scale of TWh. The objectives of UHS are (1) temporarily store the green hydrogen fully inside the reservoir, (2) maintain its purity while being stored, and (3) operate under critical stress states. Under the cyclic storage/production dynamics, fluid and rock interactions are expected to behave much more complex than the commonly studied monotonic injection or production scenarios. Indeed, cyclic transport of hydrogen in the subsurface is hysteretic, with complex transport characteristics. Furthermore, the cyclic loading of rocks motivates their plastic behaviour, especially creep and viscoplasticity. Additionally, these formations are often heterogeneous and range large length scales. As such, reliable technical feasibility studies of UHS are required to carefully consider all these multiscale complex physics. In this talk, our recent multiscale experimental-numerical study for technical feasibility of UHS is presented. The studies include laboratory measurements of hydrogen transport properties under static and dynamic conditions and benchmarking numerical models with laboratory results for cyclic rock mechanics. Existing challenges and knowledge gaps will be also presented.