To convert or not to convert: A comparative techno-economic analysis on CO2-to-methanol and CO2-EOR

With the intensification of economic activities, substantial increment of CO2 emissions has imposed a significant impact on the environment. Carbon Capture, Utilization, and Storage (CCUS) emerges as a crucial strategy to achieve the CO2 reduction target. This paper establishes a techno-economic analysis framework and compares two typical CO2 utilization processes of conversion and non-conversion types, namely CO2 hydrogenation to methanol (CTM) and CO2 enhanced oil recovery (EOR). It was found that electricity price and power consumption of H2 production are the major factors to determine the levelized cost of CTM, while CO2 transportation distance has the most significant influence on the overall economic efficiency of EOR. In scenarios characterized by low process costs and high product prices, CTM exhibits superior advantages, surpassing EOR by 1502.46 RMB/tCO2 in profitability. Notably, electricity price, as a pivotal factor, exerts varying degrees of influence on the economic comparison of the two technologies. Specially, when the electricity price is below 0.20 RMB/kWh, CTM is generally favorable. Conversely, when the electricity price exceeds 0.40 RMB/kWh, EOR emerges as the economically advantageous choice. Based on learning curve analysis, cost reduction potential for CTM and EOR is estimated to be 57.83 % and 61.75 % (till 2060), respectively. Dictated by the advancements in H2 production, the profitability of CTM become more superior around 2040. Moreover, cost reduction of CO2 capture will play a pivotal role for both CTM and EOR due to great potential in OPEX decreasing. This study offers significant implications on the relative benefits of CTM and EOR with their respective scenario assumptions, hence providing valuable references for decision making.