Sustainable Materials Selection Tool: Life Cycle Assessment of Natural Fibers for Auto Applications
Natural fibers such as coconut, hemp, and kenaf, are being researched as a replacement for glass fibers and mineral fillers in polymer composites due to potential environmental, cost, and weight-saving benefits. In addition, nano-crystalline cellulose and carbon fibers from lignin precursors are being developed to replace petroleum-based carbon fibers for performance lightweight composites. Although these natural fibers are carbon neutral as they are derived from plants, a significant amount of energy demand and carbon emissions may be associated with growing and harvesting the plants, transportation of the feedstocks, as well as processing the precursors and fibers. Only limited information is currently available on the energy and environmental impacts from using these fibers in composites. Potential weight reductions and the resulting energy savings during vehicle operation by applying these fibers need to be quantified and compared to conventional glass fiber and mineral reinforced composites.
This project will develop a life cycle model to evaluate energy and GHG emissions for bio-based materials to serve as a selection tool to determine sustainability for automotive applications of natural fiber materials, nano-crystalline cellulose fibers and carbon fibers derived from lignin. Quantification of energy and environmental sustainability performance requires modeling the biomass harvesting, transportation, processing, part fabrication, vehicle operation and end-of-life management stages.
Models will be constructed for the production of each fiber and composite formulation using existing life cycle datasets and data collected from suppliers. A set of interior applications will be identified based on structural and other performance requirements and weight reduction targets that are specific to each vehicle platform. The lightweighting implications of these bio-based materials will be modeled using fuel consumption to mass reduction correlations and/or using vehicle simulation models such as Autonomie. The life cycle model will also be used to examine the supply chain decisions for the sourcing of bio-based materials.