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Title: Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations

Abstract

A major driving force for change in light-duty vehicle design and technology is the National Highway Traffic Safety Administration (NHTSA) and the U.S. Environmental Protection Agency (EPA) joint final rules concerning Corporate Average Fuel Economy (CAFE) and greenhouse gas (GHG) emissions for model years (MY) 2016 through 2025 passenger cars and light trucks. The chief goal of this current study is to compare the already rapid pace of fuel economy improvement and technological change over the previous decade to the needed rate of change to meet regulations over the next decade. EPA and NHTSA comparisons of the MY 2004 US light-duty vehicle fleet to the MY 2014 fleet shows improved fuel economy (FE) of approximately 28% using the same FE estimating method mandated for CAFE regulations. Future predictions by EPA and NHTSA concerning ensemble fleet fuel economy are examined as an indicator of needed vehicle rate-of-change. A set of 40 same-model vehicle pairs for MY 2005 and MY 2015 is compared to examine changes in energy use and related technological change over the 10 year period. Powertrain improvements measured as increased vehicle efficiency, and vehicle mass-glider improvements measured as decreased tractive work requirements are quantified. The focus is first onmore » conventional gasoline powertrain vehicles which currently dominate the market, with hybrids also examined due to their high potential importance for CAFE compliance. Most hybrid vehicles with significant sales in 2014 were represented in the study. Results show 10 years of progress for the studied vehicle set includes lowered tractive effort of about 5.6% and improved powertrain efficiency of about 16.5%. Further analysis shows that this high rate of past progress must increase by about 50% in order to meet the 2025 CAFE standards. Examination of where certain MY 2015 vehicle compare to CAFE regulations is offered as well as some simple conjecture on what is needed to meet regulations under reasonable assumptions.« less

Authors:
 [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center (FEERC); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). National Transportation Research Center (NTRC)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1248772
DOE Contract Number:  
AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
SAE International Journal of Fuels and Lubricants
Additional Journal Information:
Journal Volume: 9; Journal Issue: 1; Journal ID: ISSN 1946-3952
Country of Publication:
United States
Language:
English
Subject:
29 ENERGY PLANNING, POLICY, AND ECONOMY; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; Corporate Average Fuel Economy; Vehicle efficiency; CO2 emissions; tractive work

Citation Formats

Thomas, John. Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations. United States: N. p., 2016. Web. doi:10.4271/2016-01-0909.
Thomas, John. Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations. United States. https://doi.org/10.4271/2016-01-0909
Thomas, John. 2016. "Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations". United States. https://doi.org/10.4271/2016-01-0909.
@article{osti_1248772,
title = {Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations},
author = {Thomas, John},
abstractNote = {A major driving force for change in light-duty vehicle design and technology is the National Highway Traffic Safety Administration (NHTSA) and the U.S. Environmental Protection Agency (EPA) joint final rules concerning Corporate Average Fuel Economy (CAFE) and greenhouse gas (GHG) emissions for model years (MY) 2016 through 2025 passenger cars and light trucks. The chief goal of this current study is to compare the already rapid pace of fuel economy improvement and technological change over the previous decade to the needed rate of change to meet regulations over the next decade. EPA and NHTSA comparisons of the MY 2004 US light-duty vehicle fleet to the MY 2014 fleet shows improved fuel economy (FE) of approximately 28% using the same FE estimating method mandated for CAFE regulations. Future predictions by EPA and NHTSA concerning ensemble fleet fuel economy are examined as an indicator of needed vehicle rate-of-change. A set of 40 same-model vehicle pairs for MY 2005 and MY 2015 is compared to examine changes in energy use and related technological change over the 10 year period. Powertrain improvements measured as increased vehicle efficiency, and vehicle mass-glider improvements measured as decreased tractive work requirements are quantified. The focus is first on conventional gasoline powertrain vehicles which currently dominate the market, with hybrids also examined due to their high potential importance for CAFE compliance. Most hybrid vehicles with significant sales in 2014 were represented in the study. Results show 10 years of progress for the studied vehicle set includes lowered tractive effort of about 5.6% and improved powertrain efficiency of about 16.5%. Further analysis shows that this high rate of past progress must increase by about 50% in order to meet the 2025 CAFE standards. Examination of where certain MY 2015 vehicle compare to CAFE regulations is offered as well as some simple conjecture on what is needed to meet regulations under reasonable assumptions.},
doi = {10.4271/2016-01-0909},
url = {https://www.osti.gov/biblio/1248772}, journal = {SAE International Journal of Fuels and Lubricants},
issn = {1946-3952},
number = 1,
volume = 9,
place = {United States},
year = {2016},
month = {1}
}