Review of worldwide geothermal project mechanisms and occurrence of induced seismicity

Geothermal energy aids in achieving ambitions for the reduction of greenhouse gas emissions by contributing to a more sustainable energy mix. In particular, geothermal energy in the Netherlands can play an important role in providing a sustainable supply for domestic and industrial heat demand. However, just like with any large scale industrial activity, the societal acceptance of geothermal energy as a sustainable energy source depends on the assessment and management of the safety and various risks associated with it. Of particular importance to geothermal energy, a technology requiring operations in the shallow to deep subsurface, is the potential occurrence of earthquakes or induced seismicity. Concerns related to induced seismicity could hamper large scale development of geothermal energy if not properly assessed, evaluated, mitigated and discussed among the various stakeholder groups. This report contributes to the discussion on induced seismicity associated with geothermal operations by providing a compilation of existing knowledge on the mechanisms of induced seismicity, by presenting detailed analysis of selected case studies worldwide, and by reviewing approaches of existing traffic light and monitoring systems. Implications for current and future geothermal projects in the Netherlands are also discussed.