Comparing the Mass, Energy, and Cost Effects of Lightweighting in Conventional and Electric Passenger Vehicles

Warren Schenler,Erik Wilhelm,Johannes Hofer

doi:10.13044/j.sdewes.2014.02.0023

Abstract

In this work the effect of weight reduction using advanced lightweight materials on the mass, energy use, and cost of conventional and battery electric passenger vehicles is compared. Analytic vehicle simulation is coupled with cost assessment to find the optimal degree of weight reduction minimizing manufacturing and total costs. The results show a strong secondary weight and cost saving potential for the battery electric vehicles, but a higher sensitivity of vehicle energy use to mass reduction for the conventional vehicle. Generally, light weighting has the potential to lower vehicle costs, however, the results are very sensitive to parameters affecting lifetime fuel costs for conventional and battery costs for electric vehicles. Based on current technology cost estimates it is shown that the optimal amount of primary mass reduction minimizing total costs is similar for conventional and electric vehicles and ranges from 22% to 39%, depending on vehicle range and overall use patterns. The difference between the optimal solutions minimizing manufacturing versus total costs is higher for conventional than battery electric vehicles.

Highlights

Many technology options exist to reduce vehicle energy use, greenhouse gas (GHG) emissions, and fuel costs
In this paper an analytic optimization approach was applied to compare the effects of light weighting on the mass, energy use, manufacturing and total costs of a midsize gasoline internal combustion engine vehicles (ICEV) and battery electric vehicles (BEV)
The results show a strong secondary weight and cost saving potential for the BEV due to the high mass and cost of the battery, but a higher sensitivity of vehicle energy consumption to mass reduction for the ICEV due to the relatively low powertrain efficiency and lack of regeneration capability

Summary

Introduction

Many technology options exist to reduce vehicle energy use, greenhouse gas (GHG) emissions, and fuel costs Among these are engine efficiency improvements, hybridization, vehicle light weighting, and other options like reduction of aerodynamic drag, tire rolling resistance and drivetrain losses. The study clearly shows the trade-off between investments in light weighting versus power train efficiency technology, the methodology has some limitations that prevent it from being used for specific drivetrain technologies. These limitations have been overcome in [5], which considers the regeneration capability of electric drivetrains and secondary mass and cost effects due to compounding of component sizes. It allows studying the sensitivity of the optimal solutions to component specific parameters such as battery energy density or battery specific cost

Methods

Results

Conclusion