Assessing Climate Mitigation Benefits of Public Support to CCS-EOR: An Economic Analysis

By storing carbon dioxide CO2 captured from the atmosphere or point sources into oil fields, carbon capture and storage with enhanced oil recovery (CCS-EOR) increases the fields’ output by raising reservoir pressures. Since CO2-EOR has been experimented with for decades and the revenues from the additional oil production improve projects’ economics, CCS-EOR is the most readily deployable CCS technology. However, public support for CCS-EOR projects is sometimes contested on the grounds that the resulting increase in oil production undermines their environmental benefits. Addressing this concern requires determining the effects of implementing CCS-EOR on global CO2 emissions. This note presents a simple approach based on a marginal reasoning consistent with economic decision-making. It produces analytical formulas that account for the effects on the global oil market of incentivizing CCS-EOR. In addition, we quantify the volume of oil that can be decarbonized by storing a tonne of captured CO2 through EOR from different perspectives. We produce numerical results based on a first-cut calibration. Results suggest that, from an economic perspective, CCS-EOR is a technology that mitigates global emissions. However, after accounting for the need to decarbonize the EOR oil, the reduction in emissions is significantly less than the stored quantity of CO2. If fully allocated to oil production, the environmental benefits of capturing a tonne of CO2 and storing it through conventional EOR can allow the oil producer to decarbonize 3.4 barrels on a well-to-wheel basis and 14.4 barrels when offsetting its oil-upstream emissions only. Fiscal incentives granted by governments to support CCS-EOR as a climate-change mitigation technology should be sized accordingly. We compare our findings to the size of the subsidy in the revised Section 45Q of the 2022 United States Inflation Reduction Act.