Author
FIELD, JOHN - Colorado State University | |
EVANS, SAMUEL - University Of California | |
MARX, ERNIE - Colorado State University | |
EASTER, MARK - Colorado State University | |
Adler, Paul | |
WILLSON, BRYAN - Colorado State University | |
PAUSTIAN, KEITH - Colorado State University |
Submitted to: Nature Energy
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/2/2018 Publication Date: 2/19/2018 Citation: Field, J.L., Evans, S., Marx, E., Easter, M., Adler, P.R., Willson, B., Paustian, K. 2018. High resolution techno-ecological modelling of a bioenergy landscape to identify climate mitigation opportunities in cellulosic ethanol production. Nature Energy. 3:211-219. https://doi.org/10.1038/s41560-018-0088-1. DOI: https://doi.org/10.1038/s41560-018-0088-1 Interpretive Summary: Multiple factors contribute to both the economics and carbon footprint of the bioenergy feedstock production supply chain including crop, climate, soils, land use history, agronomic management, and harvest and transport logistics. A high-resolution process based model DayCent, was integrated with crop production budgets, a biomass transport model, a lifecycle assessment framework, and a multi-dimensional optimization routine in order to explore tradeoffs between production costs and greenhouse gas mitigation for switchgrass cultivation across a heterogeneous real-world bioenergy landscape. We found that biomass cost and carbon footprint is affected by land use change and management intensity choices, however the distance from the biorefinery had limited effect. These results will help the biorefinery select feedstock production fields which optimize for feedstock costs and the carbon footprint. Technical Abstract: Meeting current biofuel mandates or creating future carbon-negative biopower systems requires feedstocks be sourced in sufficient quantities at low cost and with minimal environmental impact. Cultivating perennial grasses on low-quality lands is a promising feedstock supply strategy minimizing on-site impacts and leakage effects, though questions remain around the identification of most suitable lands, the productivity potential on marginal sites, and the cultivation intensity that best balances non-linear yield responses and soil greenhouse gas (GHG) footprints. In this work, fine-scale biogeochemical modeling is integrated with crop production budgets, a biomass transport model, a lifecycle assessment framework, and a multi-dimensional optimization routine in order to explore tradeoffs between production costs and GHG mitigation for switchgrass cultivation across a heterogeneous real-world bioenergy landscape. We find that biomass cost and GHG footprint are significantly affected by land use change and management intensity choices; that system design heuristics based on minimizing biomass collection radius have limited value. |