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Title: Drive Cycle Powertrain Efficiencies and Trends Derived from EPA Vehicle Dynamometer Results

Journal Article · · SAE International Journal of Passenger Cars. Mechanical Systems (Online)
DOI:https://doi.org/10.4271/2014-01-2562· OSTI ID:1159471
 [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Vehicle manufacturers among others are putting great emphasis on improving fuel economy (FE) of light-duty vehicles in the U.S. market, with significant FE gains being realized in recent years. The U.S. Environmental Protection Agency (EPA) data indicates that the aggregate FE of vehicles produced for the U.S. market has improved by over 20% from model year (MY) 2005 to 2013. This steep climb in FE includes changes in vehicle choice, improvements in engine and transmission technology, and reducing aerodynamic drag, rolling resistance, and parasitic losses. The powertrain related improvements focus on optimizing in-use efficiency of the transmission and engine as a system, and may make use of what is termed downsizing and/or downspeeding. This study explores quantifying recent improvements in powertrain efficiency, viewed separately from other vehicle alterations and attributes (noting that most vehicle changes are not completely independent). A methodology is outlined to estimate powertrain efficiency for the U.S city and highway cycle tests using data from the EPA vehicle database. Comparisons of common conventional gasoline powertrains for similar MY 2005 and 2013 vehicles are presented, along with results for late-model hybrid electric vehicles, the Nissan Leaf, Chevy Volt and other selected vehicles.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
1159471
Journal Information:
SAE International Journal of Passenger Cars. Mechanical Systems (Online), Vol. 7, Issue 4; ISSN 1946-4002
Publisher:
SAE InternationalCopyright Statement
Country of Publication:
United States
Language:
English

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