Sensitivity-guided thermo-hydro-mechanical modeling and operation of a multi-well geothermal system: A case study in the Xiong'an new area, China

Hydrothermal geothermal systems are increasingly deployed as low-carbon sources for district heating, making it essential to assess both their thermal efficiency and long-term geomechanical stability. In this study, we develop a field-scale numerical model of a multi-well hydrothermal heating system in the Xiong'an New Area, China. A coupled three-dimensional thermo-hydro-mechanical (THM) model is constructed to simulate 10 years of reservoir operation and to jointly evaluate heat extraction performance and geological stability. Distance-based generalized sensitivity analysis (DGSA) is then applied to systematically identify the parameters that exert the greatest control on thermal behavior and geomechanical response. The simulations indicate that, under the current operating conditions, the reservoir remains geomechanically stable, whereas several production wells face a pronounced risk of thermal breakthrough. Overall, injection rate and injection temperature emerge as the dominant controlling parameters, with rock heat capacity exerting an additional influence on the mechanical response. Guided by these sensitivity results, we design a sensitivity-informed injection–production strategy that mitigates thermal breakthrough and enhances long-term energy extraction. Additional THM simulations confirm the effectiveness of this strategy, underscoring its potential as a practical guideline for the design and operation of multi-well hydrothermal geothermal systems in similar geological settings. • 3D coupled THM model of a multi-well hydrothermal reservoir in Xiong'an, China. • DGSA identifies key parameters controlling thermal and mechanical responses. • Sensitivity-guided injection-production strategy mitigates thermal breakthrough.