Mitigating short-circuiting phenomena in Enhanced Geothermal Systems (EGS) holds pivotal significance for optimal heat extraction. The sustainability of EGS is inherently contingent upon the reservoir's ability to yield fluid with the requisite heat for utilization. However, natural and artificial fractures within the reservoir can disrupt the flow of injected water, diverting it from high thermal capacity areas and subsequently impacting production temperatures. Addressing this challenge, polymers have emerged as potential solutions for sealing fractures in EGS reservoirs. This paper delves into the evaluation of a High Temperature Preformed Particle Gels (HT-PPG) in sealing fractures in granite, a predominant rock type in most EGS projects encountered worldwide. The study investigates the potency of HT-PPGs in plugging fractures within a modeled EGS reservoir. Core flooding experiments were conducted on fractured granite models, with variations in HT-PPG swelling ratios and core fracture widths to determine the gel's plugging efficiency. By differing these parameters, crucial metrics – HT-PPG stable injection pressure, water breakthrough pressure, and residual resistance factor are recorded and interpreted. This analysis elucidates the behavior and efficiency of the HT-PPG in sealing fractures, providing valuable insights for practical applications. The findings presented in this study not only contribute to the understanding of fracture sealing mechanisms in granite-based EGS reservoirs, but also offer a pragmatic solution to combat short circulation and channeling issues within EGS reservoirs. This research endeavor holds promise in enhancing the longevity and sustainability of EGS reservoirs by addressing preferential flow pathways, thereby fostering the advancement of geothermal energy technology.

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