Energy Extraction Experiments in the SGP Geothermal Reservoir Model

Abstract

Much of the immense quantity of geothermal energy stored in the earth's crust is widely dispersed and occurs as hot igneous rock with permeabilities that are too low for adequate fluid circulation. Fracture- stimulation of such systems is needed to improve fluid circulation and expose new heat transfer surface in the hot rock. Hydrothermal resources which may need fracture stimulation are those with inadequate fluid content for heat removal flow rates or those in which the transit time of reinjected fluids is too rapid for adequate reheating. Fracture stimulation techniques proposed to enhance the energy recovery include hydraulic or explosive fracturing and thermal stress cracking. Experimental methods needed to evaluate the thermal extraction effectiveness of such stimulation practices and of hydrothermal reservoirs in general are a part of the Stanford Geothermal Program (SGP).