Genomic Science Program
U.S. Department of Energy | Office of Science | Biological and Environmental Research Program

Climate vs. Energy Security: Quantifying the Trade-Offs of BECCS Deployment and Overcoming Opportunity Costs on Set-Aside Land

Authors:

Elena Blanc-Betes1,2,3* (mblanc7@illinois.edu), Nuria Gomez-Casanovas1,4,5, Melannie D. Hartman1,6, Tara W. Hudiburg7, Madhu Khanna1,2,8, William J. Parton1,6, Evan H. DeLucia1,2,3,9, Andrew Leakey1

Institutions:

1DOE Center for Advanced Bioenergy and Bioproducts Innovation; 2Institute for Sustainability, Energy, and Environment, University of Illinois Urbana-Champaign; 3Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign; 4Texas A&M AgriLife Research Center; 5Rangeland, Wildlife, and Fisheries Management Department, Texas A&M University; 6Natural Resource Ecology Laboratory, Colorado State University–Fort Collins; 7Department of Forest, Rangeland, and Fire Science, University of Idaho–Moscow; 8Department of Agricultural and Consumer Economics, University of Illinois Urbana-Champaign; 9Department of Plant Biology, University of Illinois Urbana-Champaign

URLs:

Goals

Bioenergy with carbon capture and storage (BECCS) is explicitly being put forth as a cost-effective strategy to reconcile negative emissions targets with a sustainable energy supply. The deployment of BECCS at scale, however, raises concerns over land displacement, compensatory agricultural expansion (indirect land use change; ILUC), and the derived toll on emissions savings. ILUC can be minimized by targeting energy feedstock production on set-aside land. However, whether energy feedstocks can be sourced without incurring self-defeating emissions from land conversion remains unclear. The first goal of this study was to evaluate the emissions cost of sidestepping the drawbacks of ILUC. In addition, at present there is an important mismatch between low-carbon (C) scenarios that rely on sustained negative emissions and the emissions reduction pledges that lead international climate action. Further, uncertainty in effective C removal rates and the political appeal of energy independence may make energy targets more marketable and prioritize ethanol yields in climate portfolios. Therefore, the second goal was to examine the tradeoffs of the strategic deployment of BECCS targeting these intimately linked yet inherently different priorities.

Abstract

BECCS sits at the nexus of climate and energy security. The project evaluated tradeoffs between scenarios that support climate stabilization (e.g., negative emissions and net climate benefit) or energy security (e.g., ethanol production). Further, central to the sustainable deployment of BECCS, the team estimated the cost of sidestepping ILUC, including disturbance emissions (C debt) and foregone greenhouse gas emission savings from the displaced system (opportunity cost). The project’s spatially explicit biogeochemical-life-cycle model indicates that the opportunity cost increased C emissions per unit of energy produced by 14 to 36%, roughly doubling breakeven times for the initial C debt and making geologic C capture and storage necessary to achieve negative emissions from any given energy crop. The toll of opportunity costs on the climate benefit of BECCS from set-aside land was offset through spatial allocation of crops based on their individual biophysical constraints. Dedicated energy crops consistently outperformed mixed grasslands. Researchers estimate that BECCS allocation to land enrolled in the Conservation Reserve Program (CRP) could capture up to 9 teragrams of C per year from the atmosphere, deliver up to 16 TgCE per year in emissions savings, and meet up to 10% of the U.S. energy statutory targets, but contributions varied substantially as the priority shifted from climate stabilization to energy provision. An energetically optimal deployment would generate 13.3 billion liters of ethanol annually but would reduce negative emissions by 21% and the net climate benefit of BECCS by 15% relative to alternative optimization strategies. Results indicate a significant potential to integrate energy security targets into sustainable pathways to climate stabilization but highlight the tradeoffs between divergent policy-driven agendas.

References

Blanc-Betes, E., et al. 2023. “Climate vs Energy Security: Quantifying the Trade-offs of BECCS Deployment and Overcoming Opportunity Costs on Set-Aside Land,” Environmental Science & Technology 57(48), 19732–48. DOI:10.1021/acs.est.3c05240.

Funding Information

This work was funded by the DOE Sun Grant (U.S. DOE under award number 2014-3850222598) and by the DOE Center for Advanced Bioenergy and Bioproducts Innovation (U.S. DOE, Office of Science, BER program, under award number DE-SC0018420).