| Title | Unlocking the Potential of Abandoned Coal Mines for Thermal Energy Storage: A Stepwise Modelling Approach |
|---|---|
| Authors | T. Seidel, C. M. König, M. Nehler, F. Hahn |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | The WINZER project is investigating the potential and challenges of using groundwater-filled, abandoned hard coal mines for seasonal heat storage. Working alongside scientists and industry experts, the project aims to ensure the safe and efficient operation of aquifer thermal energy storage (ATES) systems in these former mining environments. A key part of this work involves monitoring the condition of an existing ATES pilot facility located in a flooded coal mine. The aim is to improve the operational safety, public acceptance and economic viability of thermal energy storage in disused mines. To evaluate the effects of the ATES system on the surrounding aquifer, numerical models are employed to simulate groundwater flow and heat transport. These models also assess density-dependent processes, the physical environment and the impact of various pumping scenarios. A stepwise modelling approach has been developed to address the complex geological and mining conditions that are typical of the Ruhr region in Germany. This approach provides a basis for understanding groundwater behaviour and forms the foundation for the numerical simulations. The conceptual model integrates digitised layouts of the underground mining infrastructure and is implemented at three different scales, offering an increasing level of detail: regional (>10,000 km²), site (~30 km²), and local (<1 km²). |