It’s Time to Start Pulling Carbon Out of the Atmosphere
Despite our best efforts, the world may not be able to reduce carbon pollution fast enough to avoid the worst impacts of climate change. The latest climate reports find that removing carbon dioxide from the atmosphere is no longer an option—it is a necessity. To restore the natural balance of carbon in the atmosphere, we must both reduce carbon emissions and pull existing carbon out of the atmosphere.
However, no carbon removal technologies have been deployed at a scale that can meaningfully address the magnitude of global climate pollution. We need more investment in research and development (R&D) to lower costs, improve performance, and assess sustainability and scalability of carbon removal technologies.
This morning, the National Academy of Sciences (NAS) released a report showing how to take carbon out of the atmosphere. The report develops a detailed research and development (R&D) agenda for atmospheric carbon dioxide removal and provides a roadmap for the federal government to support innovation in carbon removal technologies.
The agenda outlined in the NAS carbon removal report would be an important step toward reducing carbon pollution, and ITIF encourages the administration and Congress to take action to implement it.
What Is Carbon Removal?
Carbon removal includes a suite of technologies and approaches that remove carbon dioxide from the ambient atmosphere. Biological approaches like reforestation (planting trees) and farming techniques that increase carbon absorption in soils (no-till agriculture) have long been included in traditional mitigation efforts.
Technological approaches—commonly referred to as negative emissions technologies (NET)—are relatively immature but have the potential to permanently remove large amounts of atmospheric carbon dioxide and restore the natural balance of carbon levels.
Direct air capture (DAC) is a technological approach to carbon removal with large potential. DAC is not a new technology—small DAC systems have been installed in submarines, space shuttles, and other closed environments to prevent CO2 buildup from exhalation. However, using DAC to remove carbon pollution on a global scale will require substantial innovation and cost reductions.
Other innovative approaches include mineral carbonation—trapping carbon in minerals that can then be used as building materials—and technologies to enhance soil absorption of carbon. One pathway currently being explored by the U.S. Department of Energy (DOE) seeks to identify plants with deeper, more robust root systems as a means of increasing the carbon absorbed naturally in soils. This approach has the added benefits of improving soil quality, and enabling higher crop yields with less fertilizer.
Carbon Removal Is Necessary to Restore the Balance of Carbon in the Atmosphere
Scientists and policymakers are increasingly coming to view carbon removal as an essential but overlooked part of a balanced approach to addressing carbon pollution, and many energy-climate models find it impossible to achieve a carbon-neutral energy system without carbon removal. Clean energy sources can’t do it alone because there is already too much carbon pollution in the atmosphere.
Carbon removal technologies address three critical challenges to achieving a carbon-neutral economy:
- Carbon removal serves as a hedge against the risk that clean energy technologies fail to advance as quickly as needed.
- Even the most optimistic technology scenarios still include residual emissions from “difficult-to-decarbonize” sectors—such as cement and steel production, and fertilizer and plastics—for which zero-carbon alternatives do not presently exist. Mitigating carbon pollution will likely require some way to offset carbon emissions from these sectors.
- Many infrastructures and incumbent technologies have long lifetimes—a new home built today (with all of its energy needs) will still exist in 2050. Gasoline-powered cars and trucks purchased today will likely remain on the road for ten to twenty years from the date of purchase even after electric vehicles become cheaper than combustion vehicles. Carbon removal technologies help smooth the transition to a low-carbon economy by averting the need for accelerated stock turnover in sectors where that would prohibitively expensive.
Figure 1. Carbon removal technologies are essential to reversing carbon pollution.[i]
What Happens to the Carbon After It Is Captured?
Most of the carbon now being released into the atmosphere was previously safely stored underground in vast fossil fuel deposits for millions of years, and technologies exist now for returning captured carbon back underground and storing it safely and permanently.
Captured carbon can also be reused for a range of purposes, including building materials like cement, to boost plant photosynthesis in greenhouses, and even plastics and synthetic fuels. Carbon utilization, or “recycling,” provides the tantalizing opportunity to turn carbon from a waste product into a product with value. Current carbon utilization projects operate on a relatively small scale, but greater investment in carbon utilization research could dramatically expand the market for carbon-derived products.
American Leadership and Innovation in Carbon Removal Is Needed
Developing technologies to remove carbon pollution from the air and use it or store it safely is an opportunity for America to lead the world in innovation. Just as decades of federal research investments laid the groundwork for many of the technologies we enjoy today—such as fuel-efficient vehicles, lithium-ion batteries, and LED lighting—the government needs to work with the private sector to offer substantial R&D investments and incentivize the development of carbon removal strategies and technologies.
Bipartisan support for carbon removal is growing and offers one of the rare consensus issues that can bring together both parties. In February of this year, Congress extended and expanded the “section 45Q tax credit” for carbon use and storage—originally intended to incentivize carbon capture from power plants and other industrial sources—to include direct air capture. And a bipartisan group of senators have introduced legislation to create a direct air capture R&D program.
However, current U.S. investments are too small and uncoordinated to meaningfully address carbon removal research needs. And the full suite of carbon removal approaches should be pursued to insure against the risk that any one approach fails to reach maturity.
Now that we know we need to take carbon out of the atmosphere, the National Academy of Sciences has a plan for how. The report summary concludes with a powerful argument for greater federal investment in carbon removal R&D:
The committee recognizes that the federal government has many other research priorities, including others in mitigation and adaptation to climate change. Multiple reasons exist to pursue research on [negative emissions technologies] NETs. First, states, local governments, corporations, and countries around the world are making substantial investments to reduce their net carbon emissions and plan to increase these investments. Some of these efforts already include negative emissions. This means that advances in NETs will benefit the U.S. economy if the intellectual property is held by U.S. companies. Second, as climate damages mount, the United States will inevitably take increased action to limit climate change in the future. Third, the United States is already making a substantial effort, including the new 45Q rule that provides a tax credit of $50/tCO2 for capture and sequestration in saline aquifers and $35/tonne for oil and gas reservoirs, which would leverage the value of new investments in NET research. Thus, though climate mitigation remains the motivation for global investments in NETs, intellectual property and economic benefits will likely accrue to the nations that develop the best technology.
The federal government should adopt the research agenda from the NAS report, substantially increase investment in carbon removal R&D, and partner with the private sector to spur greater innovation.
[i] K Anderson and G Peters 2016 “The Trouble with Negative Emissions,” Science 354 (6309) 182-183, DOI: 10.1126/science.aah4567.