JASON Review of Enhanced Geothermal Systems

At the request of the U.S. Department of Energy, the JASON group that provides independent technical advice to the U.S. Government studied Enhanced Geothermal Systems (EGS) with a focus on i) assessment of technologies and approaches for subsurface imaging and characterization; and ii) assessment of approaches toward creating sites for EGS, including science and engineering to enhance permeability and increase the energy recovery factor. The group developed simple but effective analyses of tracer experiments and of heat-extraction strategies, and identified several promising directions of research, including: sub-surface imaging using ambient-field and non-linear seismic techniques; combined electromagnetic and tracer monitoring; field experiments at smaller-than-production length scales; and the potential for developing engineered heat exchangers at depth.