US DRIVE releases comprehensive cradle-to-grave analysis of light-duty vehicle GHGs, cost of driving and cost of avoided GHGs
The US DRIVE Cradle-to-Grave Working Group has published the “Cradle-to-Grave Lifecycle Analysis of US Light-Duty Vehicle-Fuel Pathways: A Greenhouse Gas Emissions and Economic Assessment of Current (2015) and Future (2025–2030) Technologies” Argonne National Lab Report.
The study provides a comprehensive lifecycle analysis (LCA), or cradle-to-grave (C2G) analysis, of the cost and greenhouse gas (GHG) emissions of a variety of vehicle-fuel pathways, as well as the levelized cost of driving (LCD) and cost of avoided GHG emissions. The study also estimates the technology readiness levels (TRLs) of key fuel and vehicle technologies along the pathways. The study only addresses possible vehicle-fuel combination pathways—i.e., no scenario analysis.
Co-authors are from Argonne National Laboratory; the US Department of Energy’s Vehicle Technologies, Fuel Cell Technologies, and Bioenergy Technologies Offices; the National Renewable Energy Laboratory; the Electric Power Research Institute; Fiat Chrysler Automobiles; General Motors; Chevron; and Ford.
The C2G analysis spans a full portfolio of midsize light-duty vehicles (LDVs), including conventional internal combustion engine vehicles (ICEVs); flexible fuel vehicles (FFVs); hybrid electric vehicles (HEVs); plug-in hybrid electric vehicles (PHEVs); battery electric vehicles (BEVs); and fuel cell electric vehicles (FCEVs). The selected fuel pathways were constrained to those deemed to be scalable to at least approximately 10% of LDV fleet demand in the future.
The modeling of various vehicle technologies, current and future, included powertrain configuration, component sizing, cost, and fuel economy and was performed with the Autonomie model. Autonomie is a modeling package that uses performance attributes of vehicle components to size components for a given vehicle configuration and vehicle performance attributes (e.g., time to accelerate from 0–60 mph, maximum speed, etc.), and to simulate fuel economy over various driving cycles.
These fuel economies served as an input for the analysis. The component sizes and vehicle fuel economy results were incorporated into the GREET model to evaluate GHG emissions of vehicle production and fuel cycles, respectively, while the vehicle costs were used to evaluate the LCD.
In evaluating the vehicle-fuel combinations, the study considers both low-volume and high-volume (Current Technology) cases (nominally 2015) and a high-volume (Future Technology) lower-carbon case (nominally 2025–2030).
Findings. One of the key observations from the report is that large GHG reductions for light-duty vehicles LDVs are challenging and require consideration of the entire lifecycle, including vehicle manufacture, fuel production, and vehicle operation. Larger GHG reductions for LDVs are achieved with both low-carbon fuels and vehicle efficiency improvements.
Under the Current Technology case, conventional gasoline ICEVs model to have C2G GHG emissions of slightly more than 450 g CO2e/mile (grams of CO2 equivalent per mile). Gasoline HEVs can reduce C2G GHG emissions to below 350 g CO2e/mi, as can other advanced vehicle technologies, such as PHEVs, BEVs, and FCEVs.
Lower GHG emissions are realized in the Future Technology case across all vehicle platforms due to vehicle efficiency gains, such as lightweighting and higher powertrain efficiency. Such improvements lead to C2G GHG emissions of about 350 g CO2e/mi for gasoline ICEVs and below 250 g CO2e/mi for HEVs, PHEVs, FCEVs, and BEVs.
Combining vehicle efficiency gains with low-carbon fuels, the GHG reductions generally more than double compared to vehicle gains alone. For example, gasoline ICEVs running on gasoline developed from pyrolysis of forest residues are modeled to have C2G GHG emissions of about 140 g CO2e/mi, while FCEVs running on hydrogen produced from biomass gasification have emissions of about 115 g CO2e/mi. BEVs running on wind electricity and FCEVs running on hydrogen from wind electricity have C2G GHG emissions of about 50 g CO2e/mi or less.
Not surprisingly, the report finds that high-volume production is critical to the viability of advanced technologies. In the high-volume, Future Technology case, the incremental costs of advanced technologies are significantly reduced, reflecting estimated R&D outcomes.
The study also finds that ow-carbon fuels can have significantly higher costs than conventional fuels. However, vehicle cost is the major (60–90%) and fuel cost the minor (10–40%) component of LCD when projected at volume.
|Cost of avoided greenhouse gas emissions. Top: Current Technology case. Bottom: Future Technology high volume case. Elgowainy et al. Click to enlarge.|
US DRIVE—United States Driving Research and Innovation for Vehicle efficiency and Energy sustainability—is a government-industry partnership among the US Department of Energy; USCAR, representing FCA US LLC, Ford Motor Company, and General Motors; five energy companies (BP America, Chevron Corporation, Exxon Mobil Corporation, Phillips 66 Company, and Shell Oil Products US); Tesla Motors; two utilities (Southern California Edison and Michigan-based DTE Energy); and the Electric Power Research Institute.
A. Elgowainy, J. Han, J. Ward, F. Joseck, D. Gohlke, A. Lindauer, T. Ramsden, M. Biddy, M. Alexander, S. Barnhart, I. Sutherland, L. Verduzco, T.J. Wallington (2016) “Cradle-to-Grave Lifecycle Analysis of U.S. Light-Duty Vehicle-Fuel Pathways: A Greenhouse Gas Emissions and Economic Assessment of Current (2015) and Future (2025-2030) Technologies” ANL/ESD-16/7