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Direct Air Capture – Key Takeaways from the National Academies Report on Negative Emission Technologies

By Erin Smith

Tuesday, October 30, 2018

There is growing global momentum for low-carbon technologies, which present opportunities to protect our environment and grow our economy, and decision makers are heeding these political and market signals.  Policymakers on both sides of the aisle are beginning to look to carbon dioxide removal (CDR) approaches – also referred to as negative emission technologies, or NETs—to bridge diverse energy and climate policy goals. In February 2018 lawmakers expanded tax credits for carbon capture projects and broadened eligibility to include direct air capture, a type of NET technology that removes carbon dioxide (CO2) directly from the air. What’s more, the USE-IT Act passed out of the Senate Energy and Public Works Committee and the Fossil Energy R&D Act was introduced in the House, both of which fund research for direct air capture. While the technology is still relatively new, three companies currently operate large-scale direct air capture plants and either store or sell captured CO2 for other uses, proving that the technology works. However, efficiency and cost must be improved for direct air capture to be implemented more broadly.  

The National Academies of Science Engineering and Medicine set out to examine the state of NET and direct air capture technology and released the results of its analysis in a new report. The analysis builds on a recent special report from the Intergovernmental Panel on Climate Change on pathways to limit temperature rise to 1.5 degrees Celsius (1.5C). Interestingly, all pathways that achieve 1.5C (and the majority of pathways that achieve 2C) rely on two NET approaches—afforestation and bioenergy with carbon capture and storage (BECCS)—both of which the new National Academies report says face barriers to being deployed at the level needed to achieve these targets. As a result, the National Academies report concludes significant research investment will be needed and provides a research and development (R&D) roadmap and recommended level of investment for several different types of NETs. Just as decades of federal research investment helped spearhead transformations in the energy we use, so too will it be needed to advance the next generation of technologies including NETs. Below, we summarize some of the key findings from the recent analysis, including priority research areas for NETs and direct air capture and storage technology:

  • NETs are best viewed as a critical part of the climate solution set rather than as a backstop only after anthropogenic emissions have been eliminated. Developing a broad portfolio of approaches, including NETs, improves our ability to manage climate risks.
  • Fundamentally new carbon removal options are needed, such as direct air capture, because land-based approaches including afforestation, changes in forest management, CO2 storage in soils, and BECCS are insufficient to achieve international emission reduction targets. 
  • Significant federal research investment is needed across a portfolio of NET and enabling technologies:
    1. Deployment-Ready Technologies – The four NETs below are deployment-ready but face competition for land that limits their total CO2 removal capacity, even if they are aggressively expanded. More research is needed to increase capacity and reduce negative environmental impacts in:
      • Afforestation/Reforestation
      • Changes in forest management
      • CO2 storage in agricultural soils
      • Bioenergy with carbon capture and storage (BECCS)
    2. Direct Air Capture and Carbon Mineralization – Rapid progress is needed because if cost and technological unknowns can be addressed, these solutions have nearly unlimited CO2 removal capacity.
    3. Enabling Technology – Additional research on biofuels and CO2 sequestration can help facilitate NET advancement and make our economy cleaner and more efficient.
  • The main barriers for direct air capture are high cost and energy requirements as well as insufficient economic drivers as opposed to gaps in basic scientific understanding.
  • The highest priority research need for direct air capture is pilot-scale studies funded by the Department of Energy. The Office of Fossil Energy and National Energy Technology Laboratory (NETL) have the necessary organizational capacity and infrastructure to house a direct air capture research, development, and demonstration (RD&D) program.
  • The report recommends federal research investment totaling $180-240 million/year for direct air capture to develop affordable (less than $100/ton of CO2) systems in 1-2 decades. Funding should be staggered, with an early focus on R&D that later feeds into demonstration and deployment projects over 15 years. It recommends the following federal funding:
    • Basic and Applied research$23-35 million/year for 10 years.
      • Research for better materials (sorbents and solvents) and component designs (air contactors) through many small $1-2 million projects
    • Development $13-25 million/year for 10 years
      • Scale-up of new materials and components at a scale necessary for pilot plants
    • Demonstration$30-60 million/year for 10 years
      • Establishment of a central testbed akin to NETL’s National Carbon Capture Center and a handful of pilot projects at $20 million/year each
    • Deployment$115-120 million/year for 10 years
      • Public investment made after projects demonstrate a path to viable commercial processes

There are a variety of benefits the United States stands to gain by investing in NET and direct air capture RD&D. Governments and corporations around the world are making substantial investment to reduce carbon pollution, and the nation that develops the best technology will reap the economic benefits from exporting it and seizing market share. Furthermore, the United States will likely take action to address carbon pollution in the future and investing in these technologies can help manage future regulatory risks. Finally, Congress has already begun looking at research for NETs in bipartisan fashion, including through passage of the FUTURE Act, Senate committee action on the USE-IT Act, and introduction in the House of the Fossil Energy R&D Act. These are promising technologies with crosscutting benefits that warrant much greater public investment and attention.