| Title | Spatial and Regulatory Constraints on Shallow Geothermal Energy Utilisation in Germany |
|---|---|
| Authors | Domenico C.G. Ravidà |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | Shallow geothermal energy, Policies, Site-suitability, Ground-source heat pumps, Heating and cooling sector |
| Abstract | The heating and cooling sector accounts for nearly 90% of Germany’s household energy use, exceeding 600 TWh annually. To reduce reliance on non-renewable sources, shallow geothermal energy (SGE) offers a key pathway by harnessing subsurface heat from depths below 400 m through ground-source heat pump (GSHP) systems. Nonetheless, SGE growth is hindered by nationally inconsistent assessments of its technical potential, coupled with limited access to standardised geoinformation. This contribution presents findings from the WärmeGut project, which supports the heat transition by (i) compiling and standardising SGE-relevant geodata, (ii) assessing nationwide geothermal potential, and (iii) streamlining access to geoinformation. Specifically, we present a technical analysis of GSHP site-suitability, investigating factors and regional policies that restrict the use of borehole heat exchangers across Germany's sixteen federal states. Over 40 criteria – including subsurface geology, conservation areas, environmental risk zones, existing land use, and groundwater systems - were evaluated for their impact on GSHP utilisation. Using a harmonised national classification scheme, three suitability classes were consistently mapped: suitable, conditionally suitable, and unsuitable zones. Overall, only high-priority water protection zones, covering less than 10% of the territory, are consistently deemed unsuitable across all federal states, whereas the relevance of other criteria varies regionally with geological conditions and differing environmental regulations. The outcome of this study highlights the challenges and disparities in policies governing SGE utilisation across Germany, providing a basis for the future standardisation of regulatory frameworks and an internationally transferable methodology for suitability assessment and representation. |