Exploringthe Potential of Offshore Geological CO₂ Storage in Canada:A Comprehensive Review and Future Outlook

Offshore Geological Carbon Storage (GCS) stands at the intersection of energy innovation, climate policy, and marine resource management, offering a strategic approach to reducing atmospheric CO₂ levels. Canada’s offshore regions present substantial opportunities for large-scale GCS, potentially mitigating a portion of the country’s 670 million tonnes of annual CO₂ emissions. While onshore sites have been more extensively examined, Canadian offshore formations offer an underutilized capacity that can be leveraged to achieve meaningful climate targets. This review canvasses the extensive evidence based on Canadian offshore GCS potential, drawing together multidisciplinary perspectives that address site characterization, operational practices, economic dynamics, and governance complexities. The intention is to provide a technically rigorous yet accessible overview that elucidates the requirements of safe and efficient offshore GCS. After assessing comprehensive screening criteria for offshore GCS site selection, we explore the technical intricacies that govern successful offshore GCS, spanning well construction, reservoir management, and real-time monitoring methods. The economic dimension is scrutinized with a comparative lens placed on cost structures for offshore versus onshore projects, capital expenses, and potential revenue streams. Construction and installation constitute 70–80% of offshore structure costs, with subsea CO₂ pipelines adding 10–30% to the overall project costs. Detailed analyses of Canada’s regulatory landscape reveal significant complexity, with overlapping jurisdictions and lack of legal clarity on liability and long-term stewardship. Indigenous engagement and stakeholder consultation remain critical for ensuring equitable and socially accepted project development. Throughout, the environmental and social dimensions are kept in view. Potential leakage pathways, induced seismicity, and ecosystem impacts are discussed. Drawing on best practices from established international projects, this review highlights the adaptive learning that Canada can undertake. In bringing together these diverse strandsgeoscience, engineering, economics, law, environment, and societythis review aims to illuminate practical pathways for advancing offshore GCS in Canada.