Swiss sportswear brand On is launching the Cloud X 5, one of the most popular footwear models in its portfolio, with a midsole featuring CleanCloud. According to the company, this is the first scale-up of an EVA midsole made using captured carbon dioxide emissions to exceed one million pairs. On also states that the commercial scale target was achieved four years earlier than originally planned. The technology applies to the cushioning layer of the shoe, which in standard constructions is usually made of EVA, an ethylene vinyl acetate copolymer, or polyurethane. Both materials are commonly linked to feedstocks derived from crude oil processing. In the proposed solution, however, the starting raw material is not exclusively fossil-based sources, but captured industrial CO2 emissions, which are intercepted before entering the atmosphere and combined with green hydrogen produced using renewable energy. These inputs are converted into e-naphtha, which serves as the basis for producing the final EVA foam.
On emphasizes that the material maintains the performance characteristics typical of conventional foam used in sports footwear. As Jean-Philippe Romain, Director of Polymer Science & Engineering, stated, "When you step into our new Cloud X 5, you will feel the exact same signature On cushioning, agility, and energy return you expect. There is absolutely zero compromise on performance." He also added that "In simple terms, the foam does not care about where its carbons come from." The company explains that, at the molecular level, ethylene produced from captured carbon dioxide is identical to standard ethylene, which is why the final material has the same technical data sheet as standard EVA. This means there are no differences in parameters such as molecular weight, polymer chain length, or melting point. At the same time, On notes that while the performance characteristics remain unchanged, the environmental profile of the material changes.
Environmental assessment and the role of the midsole
To estimate the environmental effects of the technology, the company carried out a life cycle assessment, LCA. The study was performed by CarbonMinds and critically reviewed by TÜV in accordance with ISO 14040/44/71, using the credit approach according to the TfS method. According to the data presented, the solution models at least 80% lower carbon emissions compared with conventional EVA production pathways based on fossil feedstocks. On indicates that the midsole accounts for more than half of the total weight of the shoe, which is why it was identified as a key area for material innovation. From the product design perspective, this means focusing on a component that has a significant share in both performance characteristics and the material profile of the finished product.
From concept to industrial scale
The company recalls that when it first announced the initiative in 2022, the proof-of-concept stage covered only five pairs of shoes, and commercial scale was not expected until the end of the decade. The project has now been expanded to a level exceeding one million pairs. Jean-Philippe Romain admits that he himself was initially skeptical about the project. As he said, "I remember my very first one-on-one with my manager when he handed me this project. To be completely honest, at first, I thought it was a crazy, silly idea." At the same time, he stressed that the initiative stemmed from a purely innovation-driven approach based on the question of whether a resource abundant in the atmosphere could be used for something beneficial and whether the problem itself could become part of the solution.
According to On, the rapid scale-up was possible primarily because of a supply-chain-based approach. The company says it developed a plug-and-play solution that can be integrated into existing chemical reactors, without the need to build entirely new production plants from scratch. In practice, the new value chain assumes that Infinium Energy converts captured CO2 emissions into liquid e-naphtha. The feedstock is then transferred to Borouge International, which converts the e-naphtha into commercially ready e-EVA pellets, subsequently used to produce EVA foam. The company acknowledges that finding partners for the project was difficult and that the concept was rejected multiple times by traditional industry players. According to On, it was Borouge International that recognized the potential of the solution and committed to its development. Cooperation with suppliers such as Infinium, a producer of e-naphtha at commercial scale, was said to accelerate the transition from concept to market implementation.
As Romain concluded, "We didn't have a massive business case, we just had a few slides, immense enthusiasm, and a big dream. But by rethinking how a supply chain can collaborate, we scaled to over a million pairs today. The speed at which we went from a single unconventional prototype to commercial-scale production is incredibly fast for the chemical and footwear industries." In the next stages, On intends to replace traditional EVA midsole units in other models across its portfolio with alternatives such as CleanCloud.
