Abstract:
Although hot dry rock resources are abundant and hold immense potential, their development faces challenges such as high development difficulties and low commercial viability. Therefore, Chinese and international engineering practices of enhanced geothermal systems (EGSs) were systematically reviewed. By applying systematic analysis, comparative evaluation, and numerical simulation, a geology-engineering integrated evaluation system covering well network deployment, well completion and stimulation, and heat exchange monitoring was established to provide data support for the commercial development of EGS. Research indicates that a mature technological system has been established internationally, which is centered on horizontal injector-producer well groups, well factory platform drilling, zipper-style volumetric fracturing, and full-cycle multi-source monitoring. In contrast, existing Chinese demonstration projects primarily rely on vertical well stimulation. These projects face critical constraints such as poor inter-well connectivity, insufficient flow capacity, and unstable reservoir stimulation effects and have not yet achieved commercial breakthroughs. Based on the above comparison, a systematic and efficient development technology roadmap suitable for the deep hot dry rock geological conditions in China was proposed. This roadmap is guided by stress-constrained well trajectory optimization, matches reasonable well spacing with refined stage and cluster design, adopts a medium-to-high displacement sand-adding volumetric fracturing process, and integrates a multi-source real-time fracture monitoring and closed-loop feedback control mechanism to establish an integrated “design-stimulation-evaluation-optimization” method for systematical reservoir stimulation of geothermal horizontal wells. This roadmap provides a theoretical foundation and a practical pathway for the efficient development of hot dry rock resources in China and the high-quality development of the geothermal industry.