| Abstract |
We propose a practical framework to assess geothermal district heating and cooling (geoDHC) market maturity in Europe by combining (i) project-level technical maturity and (ii) national public-support maturity. Using 29 geoDHC installations in 13 EU countries reported in the COST Geothermal-DHC network and the SAPHEA project, we construct a Technical Maturity index (Technology Readiness Level, system scale, and ‘human reach’) and a Public Support index (regulatory intensity and support schemes for renewable DHC) derived from the EU RED II district heating and cooling assessment. Both indices are normalised to 0–10 and visualised through a maturity matrix and GIS maps. Results reveal strong ‘pioneer’ clusters where advanced deployments align with supportive frameworks (e.g., Germany, Poland, France, Slovakia), but also systematic mismatches: technology-leading contexts with policy gaps (e.g., Romania) and policy-driven contexts with limited population reach (e.g., the Netherlands). The approach is intended as a diagnostic tool to prioritise regulatory improvements and investment support for scaling geoDHC in the EU. |