Development of a thermal fracturing model for cold CO2 injection in enhanced geothermal systems

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Due to the economic and environmental constraints on oil and gas development, there is strong demand for high performance simulation software for stimulation of deep geothermal reservoir in hot dry rock of low permeability with enhanced geothermal systems (EGS), where rock is fractured for cold water to flow through and to be heated for electricity generation. However, there is a gap in service industry to provide sophisticated fracturing simulation software to facilitate EGS. Petro-Geotech Inc. (PGI), a global progressive geomechanics and geotechnical engineering software developing company headquartered in Calgary, Canada. To keep the lead in the industry, PGI is looking to develop sophisticated reservoir and fracture simulation tools for EGS, incorporating thermal fracturing modeling. Partnered with thermal fracture modeling experts at the University of Waterloo (UW), PGI will advance development of sophisticated thermal fracturing models for EGS with higher efficiency. Project objectives include: (1) development of a cold CO2 fracturing model for EGS with heat convection properly addressed; (2) an improved CO2 fracturing model that addresses the overburden effect using the displacement discontinuity method; (3) a further improved thermal fracturing model that considers natural fractures in EGS. Project results will include a sophisticated thermal fracturing model for EGS, a product that is expected to have great potential to increase the accuracy in heat transfer, stress redistribution and thermal fracture propagation monitoring. Benefits will include more affordable geothermal energy, an additional environmental-friendly heat source, reduction in greenhouse gas, and increased heat extraction efficiency. By utilizing recyclable CO2, the technology will reduce water usage in remote areas where water supplies are difficult, and a smaller scale power generator developed from the EGS (integrated with a heating system) can be both environmentally and economically attractive in Canada. The proposed research works are believed to benefit the employment and renewable energy economy by boosting the geothermal energy industry in Canada.