Overcoming Spatial Scales in Geothermal Modelling for Urban Areas

A major component in the transition from fossil to renewable energy is the demand for district heating where geothermal energy can be a substantial option. We present results on the controlling factors for the deep thermal field below a large urban area, the city of Berlin. Therefore we analyze 3D thermal models considering conductive and mixed convective heat transport mechanisms as well as different boundary conditions. Of the controlling factors, heterogeneous thermal and hydraulic physical properties of geological units at different depths are key. That data density decreases with depth poses challenges for model assumptions for which we propose solutions.