Coffee, eggshells and lentils: The recipe for more sustainable cars?
31 January 2023
Alternative materials could be the key both to more sustainable vehicles and to less food, clothing and plastic waste within the UK, according to a new study.
Designers and engineers went beyond materials already under consideration to identify fresh sustainable options that its customers could benefit from through its SMS design study.
Using a retromod Porsche 911 interior as the basis for the research, the team led by Charlotte Jones and Ian Callum identified coffee pulp, eggshells, red lentils, walnuts and rice as viable materials for a car interior in 2030.
With thousands of tonnes of food wasted every day in the UK alone, CALLUM consulted with green-tech company Ottan to determine the most appropriate materials capable of replacing plastics, yet still meeting the rigorous design, environmental and engineering requirements of a car.
Solutions identified that could meet the temperature and wear specifications included adopting eggshells mixed with resin to create a smooth, opaque material with either a glossy or matt surface.
Application examples include the trim surround for the window switches. By adding walnut shells to the eggshells, the recycled content of Ottan’s material increases to 84 percent from 78 percent.
Out-of-date rice or lentils can be turned into a smooth translucent material, ideal for illuminated areas of the car such as lamp covers or illuminated switches. As a flame-resistant alternative, coffee pulp could replace traditional plastics for glossy, decorative trim such as dashboard inserts.
Keen to demonstrate that sustainable materials can still offer vivid colours, CALLUM identified purple carrot pulp that produces a mulberry-like colour for trim parts. Tree leaves can be recycled into a dark, smooth surface offering an alternative natural finish to wood veneers for the centre console or dashboard.
With seats requiring a blend of wear resistance, comfort and colour fastness, CALLUM opted for preloved materials that would usually go to landfill. “Around the world, we consume roughly 62 million tonnes of textiles a year and around 87 percent of the total fibre input used for clothing is either landfilled or incinerated,” says CALLUM’s Head of materials and sustainability, Charlotte Jones.
“Companies such as Planq take jeans, then shred and press them with potato or corn starch to create a hard veneer that could be used for seat shells or dash centres.
“The SMS design study was created by CALLUM to illustrate that there is another way, and we can support manufacturers and suppliers identify engineered alternatives that end consumers are increasingly looking for.”
The seat centre facings in the CALLUM design study use Camira, a fabric made from marine plastic waste such as polyester, whilst the bolster surfaces are covered in Féline, a soft material produced from PET bottles.
Each offers no weight penalty, and crucially each can be recycled again if needed. For the carpet, Jones proposes Econyl, a material that uses nylon carpets or fishing nets to create a new hard-wearing fabric.
Whilst SMS is a concept, CALLUM selected materials that can meet or have the potential to meet automotive requirements and be production feasible by 2030 – the next step is to trial the materials in upcoming projects.
Demonstrating the relevance of its sustainability studies, CALLUM has already engineered a hemp/flax composite option that buyers can now select on its latest project, the Barq EV scooter.
“More of our customers are starting to think about sustainable projects and put an emphasis on the circular economy. With others, we might nudge them down that path, highlighting the business benefits of making a more sustainable choice,” adds CALLUM Co-Founder and Design Director, Ian Callum.