Stanford Geothermal WorkshopFebruary 9-11, 2026

Fracture connectivity optimization and long-term circulation performance are crucial for Enhanced Geothermal Systems (EGS) success. This research assesses various stimulation design choices for a future well, Well 16C(78)-32, at the Utah FORGE location through a numerical sensitivity analysis. This well would be placed to the north of the existing well pair (600 ft at the heel and 280 ft at the toe). The analysis explores the combined impacts of lateral and vertical positioning, stimulation fluid type, and previous stimulation activities. Three trajectory options were examined: elevation alignment with well 16A(78)-32, a mid-level elevation placement between the two wells, and elevation alignment with well 16B(78)-32, all cases offset to the north. Each trajectory was assessed with crosslinked CMHPG and slickwater treatments, with and without considering the 2024 FORGE stimulation history. Simulated fracture hits at wells 16A and 16B were analyzed to assess hydraulic connectivity and fracture extension. The findings reveal that the vertical positioning significantly influences interwell connectivity, with mid-level placement yielding a more balanced and resilient fracture network. Crosslinked CMHPG provides more balanced and durable interwell connectivity under both unstimulated and stimulated stress conditions. Analysis of proppant settlement reveals the significance of wellbore connectivity supported by proppant in maintaining interwell communication during circulation. Continuous propped pathways between wells are crucial for sustaining effective connectivity and reduce reliance on isolated fracture segments. Large treatment designs with crosslinked CMHPG can improve interwell connectivity. Therefore, a robust design option for future EGS development at FORGE involves a mid-level trajectory for well 16C(78)-32 combined with a crosslinked CMHPG stimulation strategy.

Topic: FORGE