Abstract Achieving greenhouse gas neutrality by 2045 requires a considerable expansion of renewable heating technologies in Germany. Despite technical and environmental advantages, shallow geothermal systems remain underutilised, while air-source heat pumps and fossil-based systems still dominate the market. Barriers include unclear funding schemes, lack of standardisation, high upfront costs, skilled labour shortages, and limited public awareness. These factors contribute to investment uncertainty and delay deployment. This paper analyses the structural challenges to geothermal market growth and formulates policy recommendations for broader and faster adoption of ground-source heat pump technologies.
Klemt et al. (2026) studied this question.