title: Life Cycle Assessment of Vehicle Lightweighting: Novel Mathematical Methods to Estimate Use-Phase Fuel Consumption.
abstract: Lightweighting is a key strategy to improve vehicle fuel economy. Assessing the life-cycle benefits of lightweighting requires a quantitative description of the use-phase fuel consumption reduction associated with mass reduction. We present novel methods of estimating mass-induced fuel consumption (MIF) and fuel reduction values (FRVs) from fuel economy and dynamometer test data in the U.S. Environmental Protection Agency (EPA) database. In the past, FRVs have been measured using experimental testing. We demonstrate that FRVs can be mathematically derived from coast down coefficients in the EPA vehicle test database avoiding additional testing. MIF and FRVs calculated for 83 different 2013 MY vehicles are in the ranges 0.22-0.43 and 0.15-0.26 L/(100 km 100 kg), respectively, and increase to 0.27-0.53 L/(100 km 100 kg) with powertrain resizing to retain equivalent vehicle performance. We show how use-phase fuel consumption can be estimated using MIF and FRVs in life cycle assessments (LCAs) of vehicle lightweighting from total vehicle and vehicle component perspectives with, and without, powertrain resizing. The mass-induced fuel consumption model is illustrated by estimating lifecycle greenhouse gas (GHG) emission benefits from lightweighting a grille opening reinforcement component using magnesium or carbon fiber composite for 83 different vehicle models.
authors.affiliation: †Systems Analytics and Environmental Sciences Department, Ford Motor Company, Dearborn, Michigan 48121-2053, United States.
authors.forename: Hyung Chul
authors.initials: HC
authors.lastname: Kim
authors.affiliation: †Systems Analytics and Environmental Sciences Department, Ford Motor Company, Dearborn, Michigan 48121-2053, United States.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Wallington
authors.affiliation: ‡Board Member, Center for Sustainable Systems, School of Natural Resources and Environment, University of Michigan, Dana Building, 440 Church Street, Ann Arbor, Michigan 48109-1041, United States.
authors.forename: John L
authors.initials: JL
authors.lastname: Sullivan
authors.affiliation: §Center for Sustainable Systems, School of Natural Resources and Environment, University of Michigan, Dana Building, 440 Church Street, Ann Arbor, Michigan 48109-1041, United States.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Keoleian
mesh_terms: D005742:Gasoline / Q000032:analysis*; D017752:Greenhouse Effect; D008274:Magnesium / Q000737:chemistry; D008962:Models, Theoretical; D018986:Motor Vehicles; D013232:Steel / Q000737:chemistry; D001335:Vehicle Emissions / Q000032:analysis
chemical_list: D005742:Gasoline; D001335:Vehicle Emissions; D013232:Steel; D008274:Magnesium