back to all publications

Carbon Emission Targets for Driving Sustainable Mobility with U.S. Light Duty Vehicles

CSS Publication Number
Full Publication Date
December 31, 2008

Models and frameworks to guide "sustainable mobility" of personal transportation lack definitive quantitative targets. This paper defines sustainable mobility targets for US light-duty vehicles (LDVs) to help stabilize atmospheric carbon dioxide concentrations at 450 or 550 ppm. The Intergovernmental Panel on Climate Change carbon stabilization pathways are used to equitably distribute future carbon dioxide emissions to the US. Allowable US emissions are then allocated to the LDV sector according to the current share of national emissions. Average on-road LDV well-to-wheel carbon emissions must be reduced from 160 g/mile (2002) to 20 g/mile by 2050 to contribute to a 450 ppm CO2 goal. Strategies to reduce LDV greenhouse gas emissions include reducing travel demand, improving average fuel economy, and utilizing low-carbon ethanol. Simulations using EIA modeling parameters indicate that average LDV fuel economy must reach 136 mpg, cellulosic ethanol must make up over 83% of fuel market share, or annual LDV travel demand must be reduced by about 53% by 2050 to help meet LDV greenhouse gas targets based on a 450 ppm CO2 stabilization goal. Recent federal energy security policy and plug-in hybrid technology programs may also help meet LDV carbon emission targets in the short term by reducing gasoline use, but an aggressive combination of strategies will be needed to keep vehicle CO2 in line with an emissions target to 2050.

Research Areas
Mobility Systems
Publication Type
Journal Article
Digital Object Identifier
DOI: 10.1021/es801032b
Full Citation
Grimes-Casey, Hilary, Gregory A. Keoleian and Blair Willcox. 2009. Carbon Emission Targets for Driving Sustainable Mobility with U.S. Light Duty Vehicles.” Environmental Science and Technology 43(3): 585-590.