Automotive CO2 Emissions Characterization by U.S. Light-Duty Vehicle Platform

1
Automotive CO2 Emissions Characterizationby U.S.
Light-Duty Vehicle Platform

• John DeCicco, Feng An, Huiming Gong
• Presentation at the TRB Annual Meeting
• Washington, DC January 2005

Environmental Defense Energy and Transportation
Technologies, LLC
2
Overview

• Objectives (why look at platforms?)
• What is a platform?
• Methodology and data sources
• Platforms in the U.S. auto market
• CO2 Emissions Characterizations
• Explore variability within and across platforms
• Compare platform efficiency estimates
• Conclusions

3
Objectives
Why look at platforms?

• Link CO2 emissions and related factors to the way
  production is organized.
• Proliferation of nameplates and artificiality of
  the car-truck distinction makes traditional
  class-based analysis more difficult and less
  revealing.
• Foundation for analyzing issues of part-scale
  production and staggered design change.
• Provide a basis for assessing costs pertinent to
  production credits or similar incentives.

4
What is a Platform?

• In general, a collection of manufacturing assets
  shared among different products.
• Historically related to common chassis components
  and "hard points" for an assembly line.
• Flexible manufacturing long since obviates need
  for fixed dimensions.
• Platform ("architecture") now entails sharing of
  both "soft" and "hard" assets.

5
Platform Strategy as a Balancing Act
Maximizing the market benefits of product
differentiation
Minimizing costs througheconomies of scale
6
Data and Methodology

• EPA NHTSA data for fuel economy, matched to
  trade (Ward's) platform data
• Only up to 8,500 lb gvw, even though some
  platforms also include heavier models
• Platforms are not always "well defined"
• MY2002 sales, CY2002 platform production
• early MY2003 models not counted in sales
• Nominal, direct CO2 emissions based on 8.8
  kg/gal, 15 fuel economy shortfall
• Diesel and AFV use assumed negligible (diesel
  LDV share was only 0.1 in MY2002 estimated FFV
  credits were backed out)

7
Top Platforms Ranked by U.S. Sales
Next 5 Ford Explorer, Honda Accord, Chevy
Trailblazer, Chrysler Voyager, Chevy Malibu
8
Platform Distribution by MY2002 Sales
9
Platform Distribution by MY2002 CO2 Emissions
10
Variability within a Platform

• Factors of engines, of body styles, weight
• Examples
• GMT800 (Silverado, etc.)7 models, 5 engines, 3
  body stylesvariations 33 in disp, 26 in wt,
  23 in CO2
• Dodge Dakota/Durango 2 models, 4 engine, 2 body
  stylesvariations 75 in disp, 31 in wt, 45 in
  CO2
• Honda Odyssey / Acura MDX2 models, 1 engine, 1
  body stylevariations (0) in disp, 5 in wt, 6
  in CO2

Variation (Max-Min)/Mean sales-weighted
11
Typical Variations within a Platform

• Weight, in general, varies least median 17
• Greatest variation (26-35) in pickup platforms,
  which include body-on-frame SUVs
• Engine displacement median variation 26
• Greatest for compact pickups, with I4 - V8
  options
• CO2 emissions rate median variation 20
• Outlier is VW Jetta, with diesel 67 variation
• For others, compact pickups show 45 variation

N.B. Drive type was not examined, but other
analysis indicates typical 10-15 CO2 impact for
4- vs. 2-WD.
12
Variability Across Platforms

• Comparing platform averages (but remember the
  significant within-platform variability)
• Examined
• Power, specific power (HP/L)
• Ton-MPG
• Reciprocal of mass-normalized fuel consumption
• Isolates non-mass-related aspects of efficiency
• A good (but not perfect) index of powertrain
  efficiency

13
Platform average peak power vs. engine size
14
Ton-MPG Indeces for Selected Platforms
(identified here by representative models)
15
Ton-MPG vs. average platform weight
No correlation to weight (r -0.04)
Ton-MPGfor trucks only 5 lower than cars on
average
Some, but not all, large variations reflect
platform age ("dated"-ness)
16
Conclusions

• Platform-level data enable analysis linked to how
  the industry manages production
• Highest volume platforms contribute, by a modest
  margin, disproportionately to CO2
• Top 30 ? 69 of sales, 72 of CO2 (MY2002)
• Variability within and across platforms can
  reflect some opportunities for CO2 reduction
• Newer platforms generally more "efficient"
• Provides a baseline and foundation for several
  types of future analyses