摘要

Life cycle environmental impacts of a product or process may be global and/or spatially-explicit, such as land use change (LUC) and LUC greenhouse gas (GHG) emissions. Life cycle optimization (LCO) usually does not account for these impacts. However, for a product or process to be truly sustainable, they must be considered. We integrate computable general equilibrium (CGE)-based LUC modeling and LCO to create a novel multiobjective CGE-LUC-LCO framework to account for global environmental impacts and production costs. The framework is then applied to case studies on life cycle GHG emissions throughout the bioethanol life cycle, considering regional and global agricultural practices, land use, technological impacts, and global economic forces. The framework considers emissions from feedstock production, transportation, direct/indirect processing emissions, end use, and LUC. The model allows for selection of 16 bioethanol production pathways from 5 feedstocks, and 3 case studies with US and EU bioethanol demands are examined. The methodology identifies cleaner production strategies by considering global, spatially-explicit life cycle environmental impacts like LUC and LUC GHG emissions for the first time in LCO.