Lawrence Berkeley National Laboratory

Abstract Enhanced Geothermal Systems (EGS) have the capacity to broaden the accessible resource pool for geothermal power generation. Traditionally viewed as a “baseload” resource, their flexible operation might also enable dispatchable load‐following generation and long‐term energy storage, aligning them with the evolving landscape of decarbonized electricity systems. However, increasing permeability and extracting energy during EGS operations can induce microseismic events; for many prior EGS efforts, some associated seismicity has been observed. While energetically beneficial, the flexibility of EGS operations prompts our inquiry into whether new types of operations will yield previously unseen seismicity patterns. We demonstrate the use of distributed acoustic sensing (DAS) with real‐time edge computing to monitor seismicity during a pilot test of a cyclically operated EGS facility at the Blue Mountain geothermal field. Our focus lies in uncovering seismicity insights from the real‐time microseismic catalog, particularly during load‐following dispatchability tests simulating flexible EGS operation. We find that variations in pore pressure consistently correlate with seismicity, and that controlling pressure cycles during flexible operations appears to constrain microseismic activity during subsequent cycles. The spatio‐temporal evolution of microseismic clouds recorded during cyclic injection cycles fits diffusive models over our available observation period. Additionally, seismicity elevation lags behind pore pressure increases, likely due to pressure diffusion to the fracture system boundary. Through real‐time monitoring, we offer novel insights into seismicity associated with flexibly operating EGS. Our findings suggest that leveraging DAS and edge computing can inform EGS operations and help mitigate induced seismicity. Plain Language Summary Enhanced Geothermal Systems (EGS) enhance subsurface permeability to allow fluid circulation through hot rock formations deep underground. EGS development uses high‐pressure fluid injections to create or reopen fractures. While geothermal power is often viewed as a steady‐state (baseload) resource, increasing demand for flexible, low‐carbon power generation highlights the potential of EGS to adapt to fluctuating energy needs and store energy longer, aiding transition to cleaner electricity systems. It is known that conventional EGS operations can trigger microseismic events, but seismicity related to flexible operations, like cyclic injections, is less studied. To investigate this, we developed a real‐time seismic acquisition and processing framework that uses borehole distributed acoustic sensing (DAS) to monitor small seismic events during flexible EGS operations. This system operates on the “edge,” meaning computation happens close to where data is collected, avoiding the need to transfer large datasets for analysis. We deployed this framework during an EGS pilot at Blue Mountain, where flexible production methods were tested. Our results showed a consistent relationship between changes in pore pressure and seismic activity. Seismicity during injection cycles exhibited a diffusive pattern, and there was a delay in seismic activity following pressure changes, offering insights that could improve seismicity mitigation strategies. Key Points Real‐time distributed acoustic sensing (DAS) reveals pressure‐dependent behavior of seismicity during cyclic EGS operations The spatio‐temporal evolution of microseismic clouds recorded during cyclic injection cycles exhibit diffusive‐like properties Combining DAS with edge computing shows the potential to inform protocols for induced seismicity mitigation in an EGS context