Cyclic CO₂ storage and geothermal energy extraction using a huff and puff technique in the Basal Cambrian Sandstone Unit, Canada

In this study, a single horizontal well huff and puff (cyclic) CO2 injection and hot water production system has been investigated to combine CO2 storage with geothermal energy extraction in the Basal Cambrian Sandstone Unit (BCSU) in the province of Alberta, Canada. The results reveal that the cyclic CO2 plume geothermal process realizes total CO2 storage amount and cumulative energy production varying between 10.9 and 100.8 million m3 and 69.1 to 140.2 GWht, respectively. In each cycle, it was found that the shut-in period was beneficial for CO2 storage. The thermal Energy Produced to Energy Invested (tEPEI) ratios indicate that most cases can be considered as efficient geothermal production systems for heat production. Although cases with the highest CO2 injection may not be efficient for geothermal energy production, the thermal energy produced from these cases was greater than the compression energy invested for CO2 injection. This study describes a new option to combine both CO2 storage and geothermal energy production.