To achieve climate goals, the subsurface offers great opportunities for the large-scale storage of fuel-based energy carriers (UHS), heat (UTES), mechanical energy (CAES), green-house gases (CCS) and wastewaters. All these activities have a direct impact on the shallow/deep subsurface environment, as they can cause physical, chemical and microbiological changes in the underground reservoirs. Failure to understand, predict, monitor and mitigate its consequences can have significant negative implications for the use of the subsurface for energy transition purposes. Processes such as consumption and contamination of the stored hydrogen by biogeochemical reactions (e.g. dissolution, reprecipitation (clogging), souring) are examples of how the integrity and properties of the reservoir, as well as that of the facilities, can be affected. These processes, in turn, can reduce the storage performance and seriously affect its safety, health, environment and economics. These risks can greatly impact the societal acceptance of these – still developing – technologies, which are otherwise so important for achieving climate goals. One of the greatest difficulties in understanding and studying these processes is the limited availability of knowledge and data.
This session invites studies on the physical, chemical and microbiological processes that might influence subsurface energy transition activities. We encourage not only studies that increase the knowledge about these processes, but also monitoring and mitigation measures or best practices. Modelling, laboratory and (screening) field studies are welcome.