| Title | Reducing Drilling Costs and Maximizing Energy Extraction in a Geothermal Well with Advanced Temperature-Pressure Management Controllers |
|---|---|
| Authors | Yifan Zhang, Xu Duan, Santiago Callerio, Pradeepkumar Ashok, Dongmei Chen, Eric van Oort, Chuck |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | Effective management of downhole temperature and pressure is critical for both drilling and production of geothermal wells to ensure well integrity, optimize energy extraction, reduce operational risks, and improve project economics. This study presents a novel and field-validated approach for real-time temperature and pressure management in high-enthalpy geothermal wells, demonstrated through extensive testing in a ~11,500-ft research well with a bottomhole temperature (BHT) of approximately 275 ℉. The proposed solution integrates a high-fidelity physics-based drift-flux model, high-resolution distributed sensing, data-driven system identification, and robust control algorithms to address thermo-pressure challenges across geothermal operations. Downhole temperature and pressure data were acquired using state-of-the art wired along-string telemetry during drilling and fiber-optic distributed sensing during production in a test well located in Grimes County, Texas. These datasets were used to validate the developed drift-flux model under both normal (drilling) and reverse (production) circulation, demonstrating its potential as a real-time geothermal well digital twin. Control strategies, including both SISO (single-input-single-output) and MIMO (multi-input-multi-output) controllers, were derived from the physics-based and data-driven models. These controllers were deployed in the field using fluid flow rate, inlet fluid temperature, and choke opening as primary control inputs. MPD (managed pressure drilling), MTD (managed pressure drilling), and managed geothermal production were successful demonstrated. Field results confirmed the system’s ability to rapidly suppress thermal-pressure shocks, maintain downhole conditions, and effectively improve energy recovery efficiency. Overall, this work delivers a practical and novel well temperature and pressure management framework that addresses key engineering challenges associated with geothermal wells. |