California CO2 Storage Capacity Assessment with Updated Exclusion Zones and Storage Suitability

Abstract We reassessed California’s geological storage capacity for carbon dioxide (CO2) considering updated exclusion zones, for factors such as parklands, and storage suitability criteria. We first compiled data from basin and formation scale assessments of CO2 storage capacity. Then we developed exclusion zones based on updated seismic data and regulatory guidelines. Lastly, we estimated storage suitability in 5x5 km areas using a 5-parameter scoring system. We considered three scenarios of high, medium, and low suitability and calculated the storage capacity in each class outside of the exclusion zones. We also developed water and air quality indices from CalEnviroScreen4.0 and explored the relationship between storage capacity and environmental quality. Our study provides the most up to date estimates of California CO2 storage capacity in saline formations and is the first such study to consider siting with respect to suitability and environmental quality metrics. The proposed scoring system offers a methodology to rank prospective storage sites in terms of storage capacity, opportunities to source CO2 and renewable power, and risk mitigation.