Steep reductions in carbon emissions will be critical to avoid the most dangerous impacts of climate change, but that won’t be enough. Leading climate scientists at the Intergovernmental Panel on Climate Change (IPCC) and the National Academies of Sciences have both made it clear that we also need to remove carbon dioxide from the atmosphere.
Last month, the National Academies outlined the need for billions in research over the next decade and beyond to develop the knowledge and technology we’ll need for large-scale carbon removal. The report lays out an ambitious plan, but it begs the question: Where do we start? Based on our prior analysis and conversations with experts, we’ve narrowed the Academies’ long list of priorities to six key areas that we think are most promising, urgent, foundational and potentially tractable in the next Congress:
$10-15 million per year for a national on-farm soil monitoring system and an experimental soil carbon field network
We know that there are a number of ways to build carbon in agricultural soils while also improving soil health and boosting farm profits, through measures such as planting cover crops in the winter. The carbon benefits of some of these practices are well-understood. For others, considerable uncertainty remains as to the amount and permanence of carbon storage across geographies and agricultural operations, which could impede efforts to scale up soil-based sequestration. Accordingly, the Academies proposed establishing a national on-farm soil monitoring system through the U.S. Department of Agriculture’s (USDA) existing National Resource Inventory network. The monitoring system would provide the ongoing data necessary to reduce uncertainty around carbon storage in soil types and agricultural operations over time. The Academies also proposed an experimental field network to enhance methods for building carbon in agricultural soils, to be operated by USDA and land-grant universities. Together these efforts could help unlock hundreds of millions of tons of carbon sequestration potential in croplands and rangeland in the United States.
$40-50 million per year to breed plants that store more carbon
Crops have been selectively bred for desired attributes for centuries, and we can harness this experience to help fight climate change. Agricultural scientists believe that crops can be bred to allocate more biomass to their roots without sacrificing yield, but we haven’t prioritized this attribute. One way to do this would be to breed varieties with deeper roots or “perennialize” grains and oilseeds such as corn, wheat, soybeans and sunflower by creating hybrids or domesticating wild varieties. This would allow them to store more biomass (and carbon) underground and may provide helpful spillover benefits in the form of drought resilience. The Academies proposed to quadruple current federally funded research in this area to $40-50 million per year. The research could be led by USDA, the National Science Foundation or the U.S. Department of Energy, which is spearheading crop breeding efforts through the Advanced Research Projects Agency-Energy. If successful, new seed varieties could enhance carbon sequestration in croplands while providing significant benefits to farmers and potentially without requiring shifts in management practices.
$25 million per year to tackle economic, social and environmental questions surrounding the use of biomass for energy
The impacts of biomass can vary considerably. For example, directing waste biomass to productive uses could sequester carbon that would otherwise decompose and return to the atmosphere. These uses include creating long-lived building materials and fueling power/industrial facilities with carbon capture and storage. However, some sources of biomass can negatively impact natural ecosystems or land used for food production. To ensure productive, safe and prudent utilization of our biomass resources, the National Academies recommends agencies like DOE’s Bioenergy Technology Office and Fossil Energy group collaborate with the USDA to improve capabilities for assessing the full lifecycle climate and environmental impact of different biomass types as well as the logistical constraints facing the most climate-beneficial sources of biomass.
$75 million per year for research, development and demonstration to drive down the cost of scrubbing carbon directly from the air
Direct air capture and storage technologies hold immense promise for capturing CO2 directly from the atmosphere. Captured carbon can be used in industrial products such as building materials, or carbon can be stored underground in geologic formations. High costs for initial prototypes have hindered these technologies from gaining a foothold in the marketplace. However, the Academies demonstrates how costs could be reduced considerably with further innovation. This would help ensure that these technologies are ready for cost-effective deployment in the coming years and could even put them into the competitive range of a few existing markets for CO2 (such as the California Low Carbon Fuel Standard). Over time, this could unlock hundreds of millions of tons of carbon removal opportunities in the U.S. each year. To get there, the Academies recommends that DOE invest across a portfolio of stages of R&D, including basic and applied research and development for novel materials and system designs. This would likely occur as a collaboration across DOE’s Offices of Science, Fossil Energy, Energy Efficiency and Renewable Energy, pilot-scale demonstrations, and the creation of a national direct air capture test center to independently evaluate results.
$35 million per year to advance scientific understanding of using rocks to turn carbon pollution into... more rocks
When certain types of rocks are exposed to air, they undergo a chemical reaction that transforms CO2 into a stable, carbon-based rock, in a process called CO2 mineralization. This process happens naturally, but because many of these minerals are located deep below the Earth’s surface, they only sequester a tiny fraction of the CO2 emitted from burning fossil fuels. With some clever and low-tech engineering, however, it could be possible to speed up the natural CO2 mineralization process substantially. It is too early to say what the technical potential for this option would be in the United States, but some early studies suggest it could be as high as hundreds of millions of tons per year, if a number of technical hurdles can be overcome. This research is in its early stages, and the Academies suggests more basic science. Specifically, they call for the U.S. Geological Survey and the DOE Office of Science to study kinetics and rock mechanics, map sites with CO2-reactive rocks, and analyze broader environmental impacts and social acceptance for CO2 mineralization.
$125 million per year to shore up capabilities for storing captured carbon underground, safely and effectively
The United States is endowed with significant capacity for geological storage of captured CO2, and there are several carbon capture and storage projects already up and running. But in order to realize the nation’s full potential, the National Academies study recommends continued investments in R&D. This is critical both for unlocking important emissions reduction opportunities that rely on carbon capture and for major technology-based carbon removal options such as direct air capture that will rely on carbon storage in order to scale. The Academies outlines significant research efforts in this area, including developing new approaches to selecting appropriate sites for carbon storage and predicting performance, enhancing the effectiveness of underground storage methods and improving monitoring systems. These efforts would be best advanced through a collaboration between DOE’s Office of Fossil Energy, the U.S. Geological Survey and EPA’s Office of Research and Development.
The research endeavors outlined above must be the start of a longer-term and sustained enterprise to develop and refine the capabilities for carbon removal. Basic and applied science will lead to pilot demonstrations and technology standards followed by incentives for large-scale deployment. The National Academies provides a blueprint for this enterprise, well beyond the initial investments highlighted here. If we are to avoid dangerous levels of global warming, capturing and storing carbon already in the air must be part of our climate strategy in the United States and around the world—alongside rapid reductions in emissions across sectors. It’s time to begin investing across the portfolio of carbon-removal approaches — in research, development, demonstration, early-stage deployment and enabling conditions — so that they become viable options at the scale we need them in the coming decades.