Evaluation of the CO ₂ storage potential in CO ₂ ‐enhanced oil recovery: A case study of the Subei Basin, Jiangsu Province, China

Abstract CO 2 ‐enhanced oil recovery (CO 2 ‐EOR) is an economically viable carbon capture, utilization, and storage (CCUS) technique that is widely practiced and greatly contributes to the achievement of carbon‐neutral cities. However, studies on CO 2 ‐EOR source–sink matching involving different emission sources, different carbon capture rates, and stepwise CO 2 pipeline construction are scarce. Considering four types of carbon sources, including coal‐fired power, iron and steel, cement, and chemical plants, with different CO 2 capture rates (85%, 90%, 95%, and 100%, respectively), and using a five‐phased construction plan with a 25‐year build‐up period, we developed a method for quantifying carbon emissions from different sources, calculating the effective storage of carbon in CO 2 ‐EOR and optimizing CO 2 ‐EOR source–sink matching to reduce project costs. Using the Subei Basin in the Jiangsu Province, China, as a case study, we calculated the theoretical CO 2 ‐EOR storage to be 1.7408 × 10 8 t and the effective CO 2 ‐EOR storage to be 0.435 × 10 8 t. We analyzed the completion rate of transportation pipelines, the number of connected carbon sources, and the mass of CO 2 stored, as well as the cost‐effectiveness and sensitivity. Implementation of CO 2 ‐EOR effectively reduced the total cost of source–sink matching in the five‐stage 25‐year construction approach. The reduction of CO 2 capture rates had no effect on the value of oil repelling. The capture cost significantly affected the total cost of source–sink matching, and the impacts of the carbon sources on the total cost were in the order coal‐fired power > iron and steel > cement > chemical plants. This study provides an innovative tool for evaluating the CO 2 storage potential of CO 2 ‐EOR and provides an important framework for implementing CO 2 ‐EOR and planning CCUS projects in the Subei Basin and similar regions.