ELEGANCY

Storing CO₂ underground (Carbon Capture and Storage CCS) is one technology among others that reduces emissions above ground and therefore supports the objectives of the Energy Strategy 2050.

Once the CO₂ is stored, it may escape through the borehole used to pump in the CO₂ or through faults in the rock above the reservoir meant to seal it. Those faults might not only influence the long-term containment of CO₂, but also the occurrence of induced micro-seismicity. The presence of faults in the capturing rock therefore strongly affects the site characterization process in terms of safety and risk assessment, monitoring, verification, and with respect to the risk management plan.

To study these aspects, the Swiss Seismological Service and the SCCER-SoE conduct an experiment in close collaboration with the Department of Mechanical and Process Engineering and the Institute of Geophysics at ETH Zurich, with Swisstopo and EPFL, and with scientists from Norway, the Netherlands and the UK. The experiment is part of the ELEGANCY project, which is funded by the EU and the SFOE.

The main goal of the experiment is to understand the relevant processes governing movement of stored CO₂ along faults, the occurrence of micro-seismicity and to contribute to an enhanced site characterization. This involves experimental work at the Mont Terri rock laboratory, where the scientists inject CO₂ enriched salt water into a borehole that cuts through a major fault and monitor how the fault reacts.