Influence of spatially dependent, modeled soil carbon emission factors on life-cycle greenhouse gas emissions of corn and cellulosic ethanol
[1];
- Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA
- Environment and Production Technology Division, International Food Policy Research Institute, 2033 K St. NW Washington DC 20006 USA
- Energy Resources Center, University of Illinois at Chicago, 1309 South Halsted Street Chicago IL 60607 USA
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue Urbana IL 61801 USA
Converting land to biofuel feedstock production incurs changes in soil organic carbon (SOC) that can influence biofuel life-cycle greenhouse gas (GHG) emissions. Estimates of these land use change (LUC) and life-cycle GHG emissions affect biofuels’ attractiveness and eligibility under a number of renewable fuel policies in the U.S. and abroad. Modeling was used to refine the spatial resolution and depth-extent of domestic estimates of SOC change for land (cropland, cropland pasture, grasslands, and forests) conversion scenarios to biofuel crops (corn, corn stover, switchgrass, Miscanthus, poplar, and willow). In most regions, conversions from cropland and cropland pasture to biofuel crops led to neutral or small levels of SOC sequestration, while conversion of grassland and forest generally caused net SOC loss. Results of SOC change were incorporated into the Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model to assess their influence on life-cycle GHG emissions for the biofuels considered. Total LUC GHG emissions (g CO2eq MJ-1) were 2.1–9.3 for corn, -0.7 for corn stover, -3.4–12.9 for switchgrass, and -20.1–-6.2 for Miscanthus; these varied with SOC modeling assumptions applied. Extending soil depth from 30 to 100cm affected spatially-explicit SOC change and overall LUC GHG emissions; however the influence on LUC GHG emissions estimates were less significant in corn and corn stover than cellulosic feedstocks. Total life-cycle GHG emissions (g CO2eq MJ-1, 100cm) were estimated to be 59–66 for corn ethanol, 14 for stover ethanol, 18-26 for switchgrass ethanol, and -0.6–-7 for Miscanthus ethanol.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- DOE Contract Number:
- AC02-06CH11357
- OSTI ID:
- 1392042
- Journal Information:
- Global Change Biology. Bioenergy, Vol. 8, Issue 6; ISSN 1757-1693
- Publisher:
- Wiley
- Country of Publication:
- United States
- Language:
- English
Similar Records
Incorporating Agricultural Management Practices into the Assessment of Soil Carbon Change and Life-Cycle Greenhouse Gas Emissions of Corn Stover Ethanol Production
Soil carbon sequestration and land use change associated with biofuel production: Empirical evidence