To identify these elements, the team used a Porsche 911 interior as a basis for research. It found that eggshells mixed with resin create a smooth, opaque material that can be applied to places like the trim surrounding window switches, and adding walnut shells to the substance can increase its recycled content from 78% to 84%.
Meanwhile, expired rice or lentils can be made into a translucent material that replaces plastic light covers, and flame-resistant coffee pulp can replace traditional plastics for a glossy trim in areas like dashboard inserts. Likewise, tree leaves can be repurposed into a dark surface resembling wood veneer, ideal for the centre console or dashboard.
The team also explored clothing and plastic waste for use in upholstery fabrics and carpeting, and plant-based dyes for adding colour – for instance, purple carrot pulp produces a mulberry shade. While the selected materials already meet automotive requirements in terms of durability, the next step is to trial them in upcoming projects.
As discussed in CMF Industry View: Automotive 22/23, car brands are rapidly scaling up the adoption of eco-friendly elements, particularly for electric vehicles. For more biomaterial innovations, see The Biodesign Landscape 2022 and The Brief.