| Title | Novel Frac Sleeve Design for Water Conformance in Enhanced Geothermal Systems (EGS) Leads to Improved Thermal Efficiency |
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| Authors | Steven Fipke, Thomas Vonk, Taylor Stein, Darrell Adkins |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | Enhanced Geothermal System (EGS) technology continues to demonstrate commercial viability and deliver more gigawatts of clean energy. The relationship between the injector and producer wells is becoming clearer with more downhole data, and an opportunity for improved water distribution, or conformance, is being studied. Injectivity tests with production logging tools (PLT) to monitor water flow rates into the network of fracture stimulation stages demonstrate very unbalanced downhole water distribution. Poor conformance means the injected water cannot absorb the optimal heat energy, and the heat reservoir is not optimally depleted. Several operators have expressed concerns about water conformance in EGS wells and are pursuing technical solutions that are compatible with multi-stage frac operations and provide some form of in-reservoir flow control. An innovative approach to water conformance in fractured reservoirs was recently deployed in Algeria, using ported frac sleeves to control water breakthrough. This strategy involved using 3 ported sleeves per stimulation stage, each sleeve being configured differently to 25%, 50% and 75% of open flow area. Pending the results of a PLT log, any combination of the 3 sleeves can be shifted-closed to balance the flow rates between the frac stages, achieving a more even injection/production profile in the well. This solution could be applied to EGS wells to achieve the objectives of both effective fracture stimulation and balanced water injectivity across the lower completion. The study will include nodal analysis of water distribution based on stimulation heterogeneity, and an analysis of the choking effects of different sleeve closure scenarios. |