Datta Aparajita, Krishnamoorti Ramanan
Department of Political Science, University of Houston, Houston, Texas77204, United States.
Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States.
Environ Sci Technol. 2023 Feb 7;57(5):2084-2092. doi: 10.1021/acs.est.2c05194. Epub 2023 Jan 24.
Direct air capture (DAC) is a decarbonization solution to remove carbon dioxide (CO) from the atmosphere. The key challenges for accelerating DAC deployment are its energy requirements, high capital costs, and finding low-risk and low-cost sequestration or utilization pathways. Deploying DAC facilities proximal to sequestration or use sites and where the supply of low-cost renewable electricity is plentiful can minimize the energy, transportation, operational, and overall costs. Moreover, the increased 45Q tax credits in the Inflation Reduction Act of 2022 can further incentivize DAC deployment. This work provides a techno-economic assessment of two configurations: temperature swing adsorption-based DAC and membrane-based DAC integrated for operation with wind energy in West Texas to provide proximal access to enhanced oil recovery (EOR) operations. We evaluate the levelized cost of DAC and the cumulative cost of sequestering a ton of CO through EOR to identify opportunities for economic viability. Finally, we determine the profitability of CO sequestration under different EOR recovery factors and oil prices. We find that opportunities to reduce costs through proximal sequestration, integration with renewable energy, and the current level of policy support in the US can significantly incentivize and rapidly accelerate the deployment of DAC, especially for membrane-based technologies.
直接空气捕获（DAC）是一种从大气中去除二氧化碳（CO₂）的脱碳解决方案。加速DAC部署面临的关键挑战包括其能源需求、高昂的资本成本，以及寻找低风险、低成本的封存或利用途径。在封存或使用地点附近以及低成本可再生电力供应充足的地方部署DAC设施，可以将能源、运输、运营和总体成本降至最低。此外，2022年《降低通胀法案》中增加的45Q税收抵免可以进一步激励DAC的部署。这项工作对两种配置进行了技术经济评估：基于变温吸附的DAC和与西德克萨斯州风能集成运行的基于膜的DAC，以便为提高石油采收率（EOR）作业提供近距离接入。我们评估了DAC的平准化成本以及通过EOR封存一吨CO₂的累计成本，以确定经济可行性的机会。最后，我们确定了在不同EOR采收率因子和油价下CO₂封存的盈利能力。我们发现，通过近距离封存、与可再生能源集成以及美国当前的政策支持水平来降低成本的机会，可以显著激励并迅速加速DAC的部署，特别是对于基于膜的技术。
