In recent years, tyre manufacturers like Continental and Michelin have been exploring the use of sustainable materials in tyre production. The goal is to reduce the dependence on petroleum-based products, such as synthetic rubber and carbon black, and instead utilize biomaterials and recycled materials like carbon black, steel, and plastic.

Some unlikely alternatives that have been considered include dandelions, PET from recycled bottles, and rice husks, which are typically considered waste in the food industry.

Continental recently announced that they will be the first to launch a tyre with a “high content” of sustainable materials on the mainstream market. Their new Ultracontact NXT tyre, suitable for both internal combustion engine cars and electric vehicles, is made up to 65% from renewable or recycled materials. Around 28% of the sustainable materials used in these tyres are certified through the International Sustainability and Carbon Certification (ISCC) process, ensuring their traceability.

In addition to the certified materials, renewable materials make up another 32% of the tyre composition, while the remaining 5% consists of recycled materials. The renewable materials include resins produced from residue in the wood and paper industries, rather than relying on petroleum-based materials.

Silica is an important component in tyre performance, affecting grip, rolling resistance, and durability. Since the 1990s, silica has been partially replacing carbon black in tyre production. Traditionally, silica has been made from sand, but it requires high temperatures of 1400°C, making it energy-intensive. On the other hand, making silica from rice husk ash involves much lower heat energy, around 100°C.

PET bottles, although made from petroleum-based raw materials, are recycled to produce polyester fibers. This circular process helps prevent bottles from ending up in landfills or being incinerated. Approximately nine to fifteen bottles are used in each tyre, depending on the size. The polyester fibers derived from recycled PET bottles are used internally in the tyre carcass.

To replace petroleum-based butadiene gas used in synthetic rubber production, a bio-butadiene made from ethanol is utilized. Ethanol can be easily produced by fermenting biomass, a process that has been in use for many years.

Carbon black, a crucial ingredient in tyres, is typically made by burning oil or gas at high temperatures. However, using recycled carbon black from old tyres helps reduce the environmental impact. This is one of the aspects covered by the ISCC certification.