Processes leading to biofilm formation (bio-clogging) and precipitation of minerals (scaling) can occur during thermal energy storage in aquifers (Aquifer Thermal Energy Storage, ATES). Negative impacts on the aquifer permeability and technical infracstructure can compromise the long-term operational safety of ATES-facilities.

The aim of this research project is to evaluate the clogging-potential in ATES-systems considering the local conditions (operations strategy, mineralogy, hydrogeology and microbiology). The interdisciplinary joint research project focusses on the investigation of mineral precipitation and the development of biofilms under variable biogeochemical conditions in two different ATES-systems: siliciclastic and carbonate aquifers. Linked to this is the release of pollutants, which also poses a risk to operational safety and is, thus, the subject of research in the project. This is intended to support the selection of locations for ATES and to sort out unsuitable locations. In addition, innovative technological approaches (CO₂ introduction, carbon addition, inorganic inhibitors) and optimized operating conditions of ATES should help to reduce the clogging potential or restore flow paths.

The Geomicrobiology Section deals with the analysis and evaluation of the influence on and through microbial activities during ATES. A comprehensive molecular-biological characterization of the rocks and fluids before, during and after perfusion experiments should provide previously unavailable data on the dynamics of the microbial communities in order to better understand the geochemical and mineralogical changes and, based on this, to be able to make forecasts of possible operational disruptions.

More information can be found on the UnClog ATES homepage.