At the 37th Stanford Geothermal Workshop in Stanford, California, the Geothermal Technologies Program at the U.S. Department of Energy (DOE) released an updated Induced Seismicity Protocol. This document supplements the existing International Energy Agency (IEA) protocol of 2009, and is intended to be a living document kept up-to-date with state-of-the-art knowledge and practices.
Induced seismicity is typically defined as small scale microseismic events which can accompany a number of industrial and energy activities. During the process of creating an underground heat exchanger in an EGS reservoir, stress patterns in the rock may change, resulting in microseismic events. In almost all cases, these events are of relatively small magnitude, and by the time the energy reaches the surface, the vast majority are rarely felt.
To promote the safety of Enhanced Geothermal Systems (EGS) projects and to help gain acceptance from the general public for geothermal activities in general, and EGS projects specifically, this Protocol clarifies the role and risks of induced seismicity, which can occur during the development stages of an EGS reservoir and the subsequent extraction of geothermal energy.
This Protocol provides a set of guidance detailing useful steps geothermal project proponents can take to address induced seismicity issues. The procedures are not prescriptive, but suggest an approach to engage and inform public officials, industry, regulators, and the general public. The procedures promote public safety and proactive sharing of information.
By establishing a framework for communication and emphasizing stakeholder needs, the Protocol will facilitate the successful deployment of EGS projects, thus increasing the availability of clean, renewable and baseload energy in the United States.