Screening for Geologic Sequestration of CO2: A Comparison Between SCO2TPRO and the FE/NETL CO2 Saline Storage Cost Model

Meeting greenhouse gas emission reduction targets will likely require identifying and assessing subsurface storage space for sequestering billions of tonnes of CO2 each year. Accomplishing this feat could include estimating the cost and capacity for thousands to hundreds-of-thousands of potential geologic CO2 storage sites with CO2 storage screening tools. In this study, we introduce a screening tool, SCO2TPRO, and compare and contrast it to the FE/NETL CO2 Saline Storage Cost model (CSSC) using publicly available databases of saline reservoir properties in the United States. We find that the two tools use different methodologies to execute site-screening: SCO2TPRO calculates dynamic CO2 injection rates and plume evolution that are used to estimate operationally realistic well spacing designs and CO2 storage capacities, whereas CSSC combines a volumetric storage estimation approach with geology-engineering well injectivity equations that can lead to an unrealistically high number of wells. These methodological differences translate into CSSC cost estimates that are several times higher than the SCO2TPRO estimates and around double for the capacity estimates. SCO2TPRO can also screen thousands of potential storage sites in seconds, which is thousands of times faster than CSSC. Lastly, we also find there is no single publicly available dataset of saline formation properties that can be used for screening across the United States.

Automated summary

This study compares two CO2 storage screening tools, SCO2TPRO and CSSC, and finds differences in methodology and speed. SCO2TPRO provides more realistic estimates and is much faster than CSSC. Additionally, there is a lack of a single dataset of saline formation properties for screening across the United States.