Is Automotive Light Weighting with Plastics A No-Brainer?
Margaret Zahller, PE INTERNATIONAL, Inc. Keith Christman, American Chemistry CouncilChristoph Koffler, PhD PE INTERNATIONAL, Inc.
LCA XII Conference, Tacoma, WASeptember 25, 2012
• Comparative cradle-to-grave LCA
• Polymers used to reduce part weight and fuel use in automotive parts
• ISO 14040/44 compliant, critically reviewed
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Project OverviewCase studies
Ford Taurus Front End Bolster
Chevrolet Trailblazer / GMC Envoy Running Board
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PE Sustainability Services
Understand Strategize Improve Succeed!
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Sustainability Improvement Journey
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Sustainability Assessment Sustainability Planning& Management
Sustainability Performance& Improvement Success Goals
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z
420.08.2012
Model Year 201052% PP
45% glass3% steel
9 lb
Functional unit
● Providing structural and component support of a vehicle front over a vehicle lifetime of 150,000 miles
● Passes the Ford latch pull test to support a load of 5,340N without separation.
Ford Taurus Front End Bolster Case Study
Model Year 200852% PP
48% steel 15.1 lb
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z
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20.08.2012
Functional unit
● Providing a stiffness satisfying GM specification within an area of 1.761 m by 0.1275 m over a vehicle lifetime of 150,000 miles
● Meets GM specification for vertical deflection
Model Year 20049% TPO top cover91% steel frame + mounting brackets
28.5 lb
Model Year 200760% PP,
40% glass13.9 lb
Chevrolet Trailblazer / GMC Envoy Running Board Case Study
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• Included production of upstream materials and energy, product manufacturing, use, and end-of-life treatment
• Design data (BOM) collected from auto industry, including scrap rates
• ACC/USLCI polypropylene (2010)
• End-of-life assumptions• 98% of steel recovered for recycling• Plastics to landfill
• Avoided burden
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Data Collection and Modeling
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• Calculated fuel reduction due to light weighting1
• Baseline products: zero fuel reduction• Lightweight products: negative “fuel consumption”
• Based on US driving cycle
• Results assessed with and without adaptation to the drive train
• Fuel reduction two to three times higher with adaptation
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1Koffler C, Rohde-Brandenburger K (2010): On the calculation of fuel savings through lightweight design in automotive life cycle assessments, Int J Life Cycle Assess (2010) 15:128-135
Fuel Consumption
Primary Energy Demand
Global Warming Potential Acidification Potential
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Ford Taurus Bolster Results
2010 bolster compared to 2008 bolster
2008 bolster is the baseline, represented by the value zero
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Primary Energy Demand
Global Warming Potential Acidification Potential
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Trailblazer/Envoy Running Board Results
2007 plastic running board compared to 2004 running board
2004 running board is the baseline, represented by the value zero
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Without Drive Train Adaptation
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Fuel Reduction Potential – Monte Carlo Results
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With drive train adaptation
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Fuel Reduction Potential – Monte Carlo Results
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• Even assuming no adaptation
• Lighter products outperform the baseline for global warming potential and primary energy demand
• Bolster also performs better than the baseline for acidification potential
• With Adaptation
• Lightweight parts perform even better across all impact categories
• Increasingly likely with CAFE standards
• Greater benefit if parts recovered at end of life
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Conclusions
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Thank You