SPECIAL REPORT: SUSTAINABILITY SRI has announced that this process will now include aerodynamic simulation. While ICE vehicles lose a large proportion of energy to heat, EVs aren’t subject to the same amount of heat loss. Instead, air resistance contributes to EV energy loss. According to the tire maker’s research, 20-25% of the energy loss due to air resistance in an EV passenger car is related to the tires. Around 34-37% of the energy loss in EVs is attributed to the tires, if rolling resistance is included. Ki Jong Kil, VP of the RE development department at Hankook Tire, says, “With the ProDurable Compound, Ion [Hankook’s EV-specific high-performance line] has achieved a remarkable 31% boost in mileage (with the Ion Evo), demonstrating how incorporating cutting-edge fillers and flexible rubber materials can sustainably extend tire life.” Arguably, another significant influence tire makers can have on their Scope 3 emissions comes in the form of marketing campaigns. “The growing environmental awareness of customers is leading us to focus even more on environmentally friendly technologies and materials,” says Robb. There is a circular notion, in this sense, to inform the customer of sustainability initiatives which, in turn, increases their awareness and drives demand for these products from environmentally aware demographics. Hence, a spot on a global stage is vital to reach new customers. Bridgestone has been announced as the new Formula E tire supplier from 2026. Taking over from Hankook, the company will have an opportunity to showcase its tires in this electric motorsport competition. The racing series promotes sustainable practices by using a set maximum number of tires and the same tires for the majority of weather conditions. The Formula E tender specifies an all-season, grooved, ‘baseline’ tire with the only other option a ‘typhoon’ tire for heavy rain conditions. As is now becoming the case in a range of motorsport applications, manufacturers view demonstration of their technologies in extreme conditions as an opportunity to prove the effectiveness of higher levels of sustainable materials in tires. End of the road “ 24 Finally, end-of-life tire processing enables certain materials to be recovered from the tire. Top: Sumitomo Rubber Industries’ new aerodynamic simulation method calculates the aerodynamics of a rotating tire, including the tire pattern and changes in the tire shape in contact with the surface Above: Comparison of energy loss at a speed of 100km/h between ICE vehicles and EVs Incorporating cutting-edge fillers and flexible rubber materials can sustainably extend tire life” Ki Jong Kil, VP, RE development, Hankook Tire “We rely on the mechanical processing of end-of-life tires,” Robb says. “Rubber, steel and textile cord in particular are separated, in a highly sophisticated process, from one another. The rubber is then prepared for reuse as part of new rubber compounds.” Although preparing materials to go back into the production line can be an energy-intensive process, with the support of renewable energy this contributes to increasing the circularity of products. To reach ambitious targets – such as Hankook’s goal to use 100% sustainable materials for all its tires by 2050 – the potential to reuse or recycle must be considered at the raw material stage. “We take a holistic approach to make the material sourcing, production and use of our tires – as well as the retreading and recycling of end-of-life tires – as environmentally friendly, energy efficient and carbon neutral as possible,” adds Robb. To an extent, this will involve reimagining aspects of the supply chain to reduce Scope 1, 2 and 3 emissions. The defining progress tracker, however, is likely to come in six years when manufacturers arrive at interim deadlines that were set for 2030 – giving the industry, and the world, an opportunity to see how far along the road to sustainability the tire business really is. www.tiretechnologyinternational.com March 2024