| Title | Analysis of Hydromechanical Reservoir Response During Fluid Circulation at the Fenton Hill Enhanced Geothermal System Test Site |
|---|---|
| Authors | J.H. Norbeck, M.W. McClure, R.N. Horne |
| Year | 2016 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | hydraulic fracture, shear stimulation, hydraulic stimulation, enhanced geothermal system |
| Abstract | The Fenton Hill Enhanced Geothermal System (EGS) test site was the first EGS project in the world. The major accomplishments of the project include the successful hydraulic stimulation of two deep wells creating a flow connection, fluid circulation through the geothermal reservoir for several months, and generation of electricity. We analyzed multiple datasets to develop a conceptual model of the Fenton Hill EGS fractured reservoir system. In a previous study, we analyzed and modeled the stimulation phase of the project with a fully-coupled fluid flow and fracture mechanics reservoir simulator. In this work, we investigated the two main fluid circulation experiments performed at the site. During the fluid circulation phase, our simulation results were consistent with the reported data in three distinct ways: 1) the overall reservoir impedance was improved by operating the production well at higher back-pressure, 2) the difference between injected and produced fluid volumes reduced over time, and 3) the accessible reservoir volume grew larger over time. These results suggest that our conceptual model may be appropriate for the Fenton Hill EGS site. |