The effect of lightweighting in automotive LCA perspective: Estimation of mass-induced fuel consumption reduction for gasoline turbocharged vehicles

The paper proposes a method aimed to support Life Cycle Assessment (LCA) in the evaluation of environmental benefits achievable by lightweight design solutions in the automotive field. The study is based on an in-depth calculation of car weight-induced Fuel Consumption (FC) resulting in the Fuel Reduction Value (FRV) coefficient; this is functional in modelling the use stage in a LCA perspective. The research is focused on Gasoline Turbocharged (GT) cars, since to date there is no systematic analysis of weight-induced FC reduction regarding this propulsion technology. The FRV is evaluated for a wide range of vehicle case studies representative of different classes within the 2015 European market. The assessment is performed concentrating on four standardized driving cycles in order to evaluate various driving styles both in the case of primary mass reduction only and in the case of secondary effect (powertrain adaptation in order to maintain vehicle's performance). For the vehicle case studies under consideration, FRV is within the range 0.159-0.237 and 0.252-0.477 l/100 km*100 kg respectively for mass reduction only and secondary effect. Starting from the data obtained, a criterion is refined for estimating the FRV coefficient based on car technical features. Such a method allows to estimate FC reduction precisely by means of the value of FRV closest to the specific application, and it is proposed as a valuable tool for LCA practitioners within the automotive lightweight context.