BMW, Mercedes, Volvo turn to natural fibers to make cars more sustainable

Growing demand for new, innovative materials for interior and exterior components has given a lift to renewable raw materials, natural fibers and other bio-based alternatives as automakers and suppliers look to make cars lighter and more sustainable.

The trend has put materials such as hemp, kenaf and flax in the spotlight as automakers look to respond to customer demand to lower the environmental impact of new vehicles.

Demand is so strong for sustainable materials that interiors giant Forvia in 2022 created the stand-alone company to address the growing need. The Lyon, France-based company, called Materi’act, plans to employ about 400 people and bring in revenue of €2 billion ($2.15 billion) by 2030, Forvia said. It develops materials with up to 85 percent less CO2 emissions compared with conventional ones. Products include “green” steel made using sustainable energy, low CO2 carbon fibers, and recycled, bio-based and carbon capturing compounds, Materi’act says.

The market for renewable materials for both car interiors and exteriors is expected to grow 10 percent a year starting in 2022, reaching $27 billion by 2027, according to India-based consultancy IndustryARC.

Making the switch

A number of premium automakers are making the switch.

BMW uses renewable raw materials, natural fibers and other bio-based materials in vehicles such as the 7 Series flagship sedan, which includes them in door trim panels and the substructure of the center armrest.

Before its phaseout, the BMW i3 used door trim panels made from kenaf fibers harvested from malva plants.

The use of renewable raw materials and natural fibers such as hemp and flax helps make the cars lighter, improving their carbon footprint, BMW said.

Upcycling household waste

BMW rival Mercedes-Benz also is changing over to new materials.

Mercedes is working with Israeli company UBQ Materials to replace cable ducts in the EQS and EQE full-electric vehicles with a material made from upcycled, unsorted household waste.

The automaker is also researching animal-free alternatives as a substitute for genuine leather as a way to conserve natural resources. It showcased materials made from renewables such as powdered cactus fibers and mycelium in the Vision EQXX.

Leather-free trim options such as microfiber nonwoven fabric made with up to 73 percent recycled material are available in the Mercedes A-Class.

In addition, this year Mercedes will begin offering upholstery fabrics made from up to 100 percent recycled PET bottles. It will also utilize nylon yarn from recycled carpets and fishing nets for floor coverings in the EQS.

Door handles in the EQE and S-Class are made from a combination of biomethane and pyrolysis oil from scrap tires.

Future models will feature more sustainable recycled materials, including a CO2-based foam for rear seat cushions that chemically binds CO2, reducing emissions released into the atmosphere.

‘Strong sustainability story’

Volvo is also dedicated to making its interiors more sustainable. Dan Fidgett, who is Volvo’s head of colors and materials, is looking into closed-loop recycling systems and materials that can have a second life.

"For the EX30, if a material didn’t have a strong sustainability story and if we didn't feel that there was a route to make it circular, we dropped the development straightaway," Fidgett told Automotive News Europe. "Natural materials and recycled materials are the two lenses through which we are looking to reach our sustainability targets."

The EX30 design team turned to Swiss company Bcomp and its ampliTex fibers, which are used on the small SUV’s dashboard and door trim.

The EX30 design team turned to Swiss company Bcomp and its ampliTex fibers, which are used on the small SUV’s dashboard and door trim.

Per Martensson, Bcomp's chief revenue officer, said ampliTex utilizes renewable flax fibers from Europe, providing strength and durability while reducing environmental impact.

"The fabrics provide superior lightweighting and stiffness compared to synthetic composites, along with benefits such as high vibration damping and improved safety due to their non-shattering properties upon impact," he said.

The ampliTex fabric is then laid over Bcomp's powerRibs structure to support it from the backside through a one-step compression-molding process in which the two elements combine to form panels that can be shaped for doors, seat backs and side panels.

Along with the EX30, the material will be used in the Polestar 3 large SUV and 5 luxury sedan.

In addition to the environmental benefits, the lightweight aspect of the materials is critical for improving range and overall energy efficiency of EVs, which are weighed down by their battery packs.

"We have always strived to make light and efficient structures," Martensson said. "Using less material also makes things more cost effective in the long run."

Leather alternative

Javier Villacampa, vice president of innovation and sustainability at interiors supplier Antolin, said in an email interview that the company is doing extensive research into natural and sustainable materials to bring alternatives to customers for their interiors.

One of the projects is PersiSKIN Auto, a vegan, plant-based, sustainable covering developed as an alternative to animal and synthetic leather.

"This innovative, ethical material is made by using the surplus from persimmon harvests," he said. "We are also including natural fibers in our instrument panel substrate proposals."

Using natural fiber technologies can halve weight and CO2 emissions compared with similar all-plastic products, Villacampa said.
Antolin’s other projects include the use of mycelium, a fungus, as a structural material for sun visors.

"Mycelium-based natural materials help reduce the environmental impact of vehicle components," he said.

The company also produces headliners made with materials obtained from urban waste and post-consumer plastic waste or based on vegetable waste, and introduced a chemical foaming technology in door panels that reduces weight by more than 20 percent.

Among Materi’act’s biomass-based products are fabrics made using hemp and pineapple fibers. The French supplier called them “disruptive vegetal alternatives.”

Retraining and circularity

Bcomp’s Martensson said the entire industry faces the challenge of implementing sustainable practices throughout production.

"At our company, we focus on finding solutions to recycle materials at all stages of production and minimize transportation between supply chain sections," he said. "We urge partners to adopt green energy practices, and there is increasing pressure from automakers to comply with sustainability requirements."

Bcomp's use of flax is a central part of the strategy, because it's one of the oldest natural fibers used and it has a very controlled supply chain.

"To not end up in a green-washing story, it was clear we had to go not for the absolutely cheapest natural fiber found on the market, but something that is actively checked and controlled," Martensson said. "We strive to minimize our footprint, but producing without creating one remains a significant challenge."

‘The really fun part’

Fidgett said he views the use of natural and sustainable fibers and components as a "retraining" of the industry, forcing automakers to think about circularity.

"It's about repurposing the stuff we've already got into something new, instead of this throw-away culture of creating something new, moving away from this concept of perfection, and as soon as something is slightly scratched or dented, we throw it away and bring in something else," he said.

To avoid that Volvo wants to have a solution ready for when a car’s upholstery wears out in which the materials can be removed, recycled, or repurposed to put into another model.

The company is also trying to find alternatives to leather and plastic, but Fidgett said the journey to a more sustainable materials future is just beginning.

"We're right at the start of the journey," he said. "We're all building the plane as we're flying it. This is the difficult aspect, but it's also the really fun part."