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In 1998 the United States Automotive Materials Partnership published the life cycle inventory of a generic US family sedan. Several years later, researchers at the University of Michigan expanded this analysis to consider the dynamic replacement decisions over the vehicle lifetime that would optimize energy and emissions performance of generic family sedan ownership. The present study provides further analysis of this vehicle by examining the life cycle cost profile for generic sedan ownership and determining the optimal replacement intervals for this vehicle based on economics. Life cycle cost for a generic vehicle was estimated as $0.37/mile for a ten year life cycle and $0.31/mile for a twenty year life cycle. This study found that while less than 10% of the generic vehicle life cycle energy (20 year) is consumed during material production and manufacturing, 43% of the total life cycle cost is associated with vehicle purchase and depreciation.

A novel application in the field of Life Cycle Assessment is presented that investigates optimal vehicle retirement timing and design life. This study integrates Life Cycle Energy Analysis (LCEA) with Dynamic Replacement Modeling and quantifies the energy tradeoffs between operating an older vehicle versus replacing it with a new more energy efficient model. The decision to keep or replace a vehicle to minimizes life cycle energy consumption is influenced by several factors including vehicle production energy, current vehicle's fuel economy and its deterioration with age, the improvement in fuel economy technology of new model vehicles and annual vehicle miles traveled (VMT). Model simulations explore vehicle replacement under incremental improvements in vehicle technology and leapfrog technology improvements such as with the PNGV (Partnership for a New Generation of Vehicles).

Automakers have the opportunity to utilize bio-based composite materials to lightweight cars while replacing conventional, nonrenewable resource materials. In this study, Life Cycle Assessment (LCA) is used to understand the potential benefits and tradeoffs associated with the implementation of bio-based composite materials in automotive component production. This cradle-to-grave approach quantifies the fiber and resin production as well as material processing, use, and end of life for both a conventional glass-reinforced polypropylene component as well as a cellulose-reinforced polypropylene component. The comparison is calculated for an exterior component on a high performance vehicle. The life cycle primary energy consumption and global warming potential (GWP) are evaluated. Reduced GWP associated with the alternative component are due to the use of biomass as process energy and carbon sequestration, in addition to the alternative material component's lightweighting effect.