Fred Joseck

Current and Future United States Light-Duty Vehicle Pathways: Cradle-to-Grave Lifecycle Greenhouse Gas Emissions and Economic Assessment

This article presents a cradle-to-grave (C2G) assessment of greenhouse gas (GHG) emissions and costs for current (2015) and future (2025-2030) light-duty vehicles. The analysis addressed both fuel cycle and vehicle manufacturing cycle for the following vehicle types: gasoline and diesel internal combustion engine vehicles (ICEVs), flex fuel vehicles, compressed natural gas (CNG) vehicles, hybrid electric vehicles (HEVs), hydrogen fuel cell electric vehicles (FCEVs), battery electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs). Gasoline ICEVs using current technology have C2G emissions of ∼450 gCO2e/mi (grams of carbon dioxide equivalents per mile), while C2G emissions from HEVs, PHEVs, H2 FCEVs, and BEVs range from 300-350 gCO2e/mi. Future vehicle efficiency gains are expected to reduce emissions to ∼350 gCO2/mi for ICEVs and ∼250 gCO2e/mi for HEVs, PHEVs, FCEVs, and BEVs. Utilizing low-carbon fuel pathways yields GHG reductions more than double those achieved by vehicle efficiency gains alone. Levelized costs of driving (LCDs) are in the range

Life-Cycle Analysis of Fuels and Vehicle Technologies

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Potential energy and greenhouse gas emission effects of hydrogen production from coke oven gas in U.S. Steel Mills.

1.00/mi depending on time frame and vehicle-fuel technology. In all cases, vehicle cost represents the major (60-90%) contribution to LCDs. Currently, HEV and PHEV petroleum-fueled vehicles provide the most attractive cost in terms of avoided carbon emissions, although they offer lower potential GHG reductions. The ranges of LCD and cost of avoided carbon are narrower for the future technology pathways, reflecting the expected economic competitiveness of these alternative vehicles and fuels.

The Advanced Energy Initiative

Energy security and climate change are long-term challenges for the transportation sector in the United States. Natural gas use in vehicles may reduce the dependence of the transportation sector on petroleum fuels, but provides only a marginal reduction in well-to-wheels (WTW) greenhouse gas (GHG) emissions. Improvement in vehicle efficiency provides a proportional reduction in both petroleum use and GHG emissions. The use of conventional hybrid electric vehicles reduces WTW petroleum use and GHG emissions by 33% compared to gasoline internal combustion engine vehicles (ICEVs). Using fossil fuels-derived natural gas for electricity and hydrogen production reduces WTW GHG emissions of battery electric vehicles and fuel cell electric vehicles by 56% and 39%, respectively, compared to gasoline ICEVs. Reductions in GHG emissions in excess of 80% compared to conventional gasoline ICEVs can be achieved with the use of renewable sources, such as wind, solar, and biomass, as energy feedstocks for electricity and hydrogen production.