Optimization under uncertainty for enhanced geothermal systems

Ahinoam (Noe) Pollack
Enhanced Geothermal Systems (EGS) generate electricity by creating an artificial subsurface heat exchange circuit. Cold fluid is injected into the subsurface and heats up as it circulates though hot rocks in a hydraulically fractured reservoir. The fluid is then pumped out of production wells and powers turbines to generate electricity. There are many uncertain parameters when creating an EGS, including: the stress field, the location and orientation of pre-existing fractures, the temperature field, and the physical mechanisms governing fracture creation. Therefore, the reservoir's response to stimulation and operation cannot be predicted with certainty. My research explores the optimization of EGS design parameters, such as the spatial configurations of the laterals, the number of fracturing stages, etc., given the subsurface uncertainty.