Dr Rachel Holland, Materials Engineer, and Dr Chris Edwards, Environmental Attribute Engineer, both at Jaguar Land Rover, explain the recent work towards reducing the environmental impact of vehicles throughout their life-cycles.
The LANDS (lightweight and sound) project investigated opportunities to develop innovative, sustainable materials with low weight and low acoustic transmittance for applications in vehicles. A variety of components were investigated, ranging from exterior components, such as front and rear wheel arch liners, through to visual and hidden interior components. The project confirmed that natural or sustainable materials can meet current automotive material standards and can be manufactured successfully, providing a benefit to the environment through an improved life-cycle.
A life-cycle assessment (LCA) gives us an understanding of the effect products have on the environment, both as an individual component and on the scale of a whole car. It was important to understand the impact sustainable materials have on the LCA. This required a quantitative assessment of the environmental impact attributed to a process or a product from ‘cradle to grave’, based on the function unit set by the study. ISO 14040:2006 defines a life-cycle as 'consecutive and interlinked stages of a product system, from raw material acquisition or generation from natural resources to final disposal'. LCA is also defined as a ‘compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life-cycle’.
For LANDS, global warming potential (GWP) is used as the key measurement and there is a significant reduction of 33.7kg CO2e, or 15.6% of LANDS materials compared with those currently used. Although this saving may seem relatively insignificant when compared with the impact of a vehicle over its life-cycle, if this saving was achieved on all of the vehicles considered in this project, it would make an annual saving of around 2,019t CO2e a year – the equivalent of the impact of around 32 Range Rovers over their entire lifetime.
The scope of this three-year project was limited to finding direct material replacements that could be used with current production methods and tooling. Further work will be carried out to understand how we can design more efficiently for these new materials to maximise the environmental benefits when designing new vehicles. The project was sponsored by Innovate UK and delivered by a consortium including Jaguar Land Rover, International Automotive Components Group Ltd, MBA Polymers, Tate+Lyle Sugars and the Wolfson Centre for Materials Processing, Brunel University London.
MBA Polymers currently produces a range of post-consumer grades of plastic recovered from end-of-life vehicles. Waste, in the form of a shredded plastic-rich mixture, separated from vehicles that would normally be headed to landfill, is directed to a state-of-the-art facility, where it is separated, cleaned, and produced into recycled polymers with consistently good quality, which can be used in the manufatcuring of new electrical and automotive parts.
During the sugar refining process, a precipitate of calcium carbonate is formed in the syrup due to the addition of Ca(OH)2 and CO2, which attract colour and other impurities from the sugar. The calcium carbonate precipitates are filtered from the sugar, having successfully completed their role in the refining process.
The filter cake is a ‘waste’ product for which they have no use in their process. However, with the analysis and characterisation carried out in this project, methods have been developed to condition the calcium carbonate so that it can be used as filler in plastics.
Jaguar Land Rover
JLR input carried out component selection and testing, benchmarking of material performance and analysis of the components selected by a life-cycle assessment (LCA).
INTERNATIONAL AUTOMOTIVE COMPONENTS group, ltd
IAC manufatures intererior and exterior components. It produced and carried out component trials during the project, ensuring manufacturing concerns and requirements were highlighted throughout.
Load space sides and Front wheel arch liners
The front wheel arch liners and the load space sides were made from a filled polypropylene, sourced from a 100% post-consumer feed stock, through the standard process currently used for production parts. Both the front wheel arch liner and the load space sides were tested at JLR, where they passed the material standards for the required components.
A commonly used material across the automotive industry for this part are polyolefins.
Load space floor
For the load floor, LANDS looked at a sandwich panel made with natural fibre and bio-based resin boards enclosing a bio-based hollow core. Testing and analysis was carried out on preliminary samples and prototype components, meeting material specifications.
A commonly used material across the automotive industry for this part is a glass fibre-reinforced sandwich composite.
The dashboard insulator developed for this project is made from the recycled felt and a mineral-loaded elastomer – this acts as a barrier and prevents unwanted noise entering the cockpit.
The new mineral-loaded elastomer formulation contains a high percentage of the calcium carbonate produced by Tate+Lyle Sugars, which has a lower density compared with the current calcium carbonate used, and could give a potential weight saving of 12%.
Initial investigation shows that, in addition to the weight saving, an improvement is also possible in sound transmission loss at key frequencies, when the mineral-loaded elastomer and felt material are used together, with no detrimental effect at the other frequencies.
A commonly used material across the automotive industry for this part is a heavy layer, mineral-loaded elastomer.
Rear wheel arch liners and dashboard insulation
LANDS produced a felt from 100% recycled materials. It was achieved by using rPET (recycled bottles or textiles) and PP from offcuts of carpets, and is used for exterior (rear wheel arch liners) and interior (dashboard insulation) components. Besides coming from post-consumer waste, this material provides a weight saving (9%) in the rear wheel arch liners.
A commonly used material across the automotive industry for this part is non-woven polyester