237 / 2024-03-14 08:41:16

Challenges and Solutions for Deep Geothermal Resource Development

Deep geothermal energy,Enhanced geothermal system,Drilling and completion,Reservoir stimulation,Heat extraction

Geothermal energy is one of the most promising renewable energy resources due to its substantial reserves, extensive distribution, minimal carbon footprint, and stability. Deep geothermal resources, including hot dry rock (HDR), constitute the majority of the geothermal energy, which is crucial for advancing China's green and low-carbon development and energy structure transformation. This paper first introduces the endowment and heat source mechanisms of deep geothermal resources in China. Then, elucidate the primary method employed in the development of deep geothermal energy. Moreover, it systematically analyzes the three major challenges based on the ongoing Enhanced Geothermal System (EGS) projects, including well drilling, hydraulic stimulation, and heat extraction. Lastly, the potential solutions for the challenges in future research is given: taking “rock characterization - drilling and well completion - hydraulic stimulation - heat extraction - integrated control” as the main route; exploring the dynamic mechanical response of the rock failure and connectivity characteristic of the fracture network; clarifying the thermal-hydraulic-mechanical-chemical coupling mechanism in the process of heat extraction; and forming the new theory and method of developing deep geothermal energy, which is expected to provide the theoretical foundation for the efficient exploitation of deep geothermal resources.