A holistic framework for evaluating gigaton scale geological CO2 storage applied to the Alberta oil sands: Physics, policy, and economics

Carbon capture, utilization, and storage (CCUS) is capable of significantly reducing anthropogenic carbon dioxide (CO2) emissions. In the Canadian context, CCUS is an important tool in mitigating emissions in the oil and gas sector, which is a significant contributor of greenhouse gas emissions in Canada. Previous studies have demonstrated the viability of CCUS in the Alberta oil sands but have not considered all the critical factors impacting the success of a CCUS system including the availability of emission sources, the design of a CO2 transportation network, the availability and capacity of suitable storage sites, the long-term fate of injected CO2, the economic viability of the system, and the overall policy environment. We consider all these factors in proposing a CCUS hub that captures CO2 from a cluster of 10 large oil sands emitters for permanent storage in the Devonian Nisku and Wabamun saline aquifers. We forecast the oil sands emissions using a logistic model and simulate the pressure evolution and CO2 plume migration to show that the aquifers can safely store the entirety of forecasted emissions, which amounts to over 1.9 gigatons by the end of the century. We design a pipeline network connecting the emitters and the storage formations, which is estimated to cost approximately $ 4-billion. We consider both privately-funded and publicly-funded scenarios for financing the pipeline network, taking into account relevant financial and policy incentives. Our work outlines the key points that must be considered when designing a large-scale CCS system, namely availability of emission sources, efficiency of pipeline route, storage capacity and injectivity, CO2 migration and trapping, cost, and policy and financial incentives. This provides a comprehensive framework upon which future CCUS projects can be evaluated to ensure its long-term viability and success.