Two months after the stimulation and the well being shut in for the winter, we are pleased to have had the opportunity to present our results to the geothermal community at the 38th Stanford Geothermal Workshop. During the Wednesday morning session of talks on EGS, Susan Petty and Trenton Cladouhos of AltaRock presented our stimulation results to a crowd eager to hear of our progress.
Presentation by Susan Petty
Susan’s presentation focused on our efforts to gather information and data to develop our comprehensive operation plan before engaging in the permitting process and various public outreach campaigns (including this blog!).
She also addressed the timescale of field work at the project site, confirming that the highly anticipated Newberry EGS Demonstration has finally become reality. Susan also addressed the effectiveness of the diverers usedduring stimulation, showing marked improvements in well permeability and evidence of stimulation/diversion locations from continuous temperature monitoring within the well.
Overall, the stimulation results presented by Susan were well received at Stanford, and the geothermal community posed many questions about our diversion practices and the implications it has on performing future EGS stimulations in a cost-effective way.
Presentation by Trenton Cladouhos
Trenton presented further evidence of our success at Newberry, discussing the details of our seismic monitoring during the stimulation. Trenton laid out how monitoring can enhance geosciences and engineering techniques, and he described other procedures essential to the expansion of EGS.
Trenton showed that our improvements to the local seismic network made it possible to detect micro-events. This allowed us to monitor the progress of the stimulation, detecting micro-events previously invisible to existing seismic detection equipment. The locations of over 100 events detected by the network showed that over the course of the stimulation, the diverter caused a shift in the location of the local micro-seismicity. This was further indication of our diversion’s effectiveness.
Finally, Trenton shared some of the lessons we learned regarding EGS seismic monitoring, including how crucial the borehole monitoring stations we installed were to the stimulation. The crowd at Stanford was pleased and amused to learn that even our largest events were barely noticeable on surface stations, which seemed to be more effective at detecting cars and trains than seismicity from EGS.