16. Sep 2026
From pollution to performance: CO2-based EVA midsole
Traditional sports shoe midsoles rely heavily on fossil fuels. As the primary cushioning layer of a shoe, the midsole is almost always made of EVA (ethylene vinyl acetate) or PU (polyurethane) – foams derived directly from crude oil processing. CleanCloud™ disrupts this cycle by using captured CO2 emissions as raw material.
Industrial carbon emissions are intercepted before they can enter the atmosphere and are combined with green hydrogen produced using renewable energy. Together, these elements are transformed into e-naphtha, which serves as the base ingredient to produce the final EVA foam. The result is a high-performance foam that turns industrial carbon emissions into a key ingredient for the brand’s shoes.
Uncompromised performance – lower carbon footprint of midsole
“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”, said Jean-Philippe Romain, Director of Polymer Science & Engineering at Swiss athletic shoe and performance sportswear producer On. “In simple terms: the foam does not care about where its carbons come from.”
The performance of the shoe is identical to traditional EVA because, on a molecular level, the ethylene produced from captured carbon is identical to standard ethylene. The resulting material shares the exact same Technical Data Sheet (TDS) as standard EVA, meaning that parameters like molecular weight, polymer chain length, and melting point are indistinguishable.
While the performance is identical, the environmental impact is not. To accurately assess the environmental benefits of the technology foam, On conducted a comprehensive Life Cycle Assessment (LCA). Performed by CarbonMinds and critically reviewed by TÜV in accordance with ISO14040/44/71, following the credit approach according to the TfS method, this study models at least 80% lower carbon emissions compared to conventional manufacturing pathways. The LCA was a cradle-to-gate assessment based on modelled scenarios and secondary data. The results represent potential environmental performance under defined assumptions and should not be interpreted as verified product-level emission reductions. The assessment looked at 3 potential pathways:
1) Conventional fossil-based EVA : The climate change impact is 3.12 kg CO2eq per kg EVA
2) CCU-based EVA – credit approach: The impact is 0.4997 kg CO2eq per kg EVA. This calculation, is aligned with the "Together for Sustainability" (TfS) industry guidelines. It reflects a circular economy model by granting a "credit" for using captured carbon, which represents the benefit of avoiding the emission. This results in a modelled reduction of approximately 84% in greenhouse gas emissions compared to the fossil-based pathway.
3) CCU-based EVA – cut-off approach: The impact is 4.32 kg CO2eq per kg EVA. This alternative approach treats the captured carbon as a "zero-burden" raw material but gives no credit for its use. The resulting footprint is higher because it accounts for the energy-intensive processes of capturing and converting the CO2 without factoring in the benefit of emission avoidance.
Both alternative pathways 2 and 3 give are scientifically valid values under ISO 14040/44, but they represent different accounting frameworks. This shows that accounting frameworks matter immensely, for transparency On presents both.
Because the midsole accounts for more than half of the shoe's total weight, On has prioritized it as a material innovation focus.
From a "crazy idea" to global scale
“I remember my very first 1-on-1 with my manager when he handed me this project. To be completely honest, at first, I thought it was a crazy, silly idea”, said Jean-Philippe. “This initiative came purely from a raw innovation mindset: Can we take a resource that is abundant in the atmosphere and do something positive with it? Can we make the problem part of the solution?”
When On first announced this initiative in 2022, the proof-of-concept had only produced five pairs of shoes, with commercial scale targeted for the end of the decade. Today, On is scaling to over a million pairs four years ahead of schedule.
The supply chain breakthrough: a plug-and-play solution
The brand was able to achieve this rapid acceleration because CleanCloud is fundamentally a supply chain story. By collaborating directly with chemical companies, On has engineered a plug-and-play solution that integrates into existing chemical reactors, allowing them to scale fast without building entirely new factories from scratch.
This entirely new chemical value chain relies on Infinium Energy (Sacramento, CA, USA) to convert captured CO2 emissions into liquid e-naphtha. The material is then handed over to Borouge International (Vienna, Austria), a leading global polymers player, who transform the e-naphtha into commercially ready e-EVA pellets, which are subsequently used to produce EVA foam. The whole process functions under the mass balance approach.
Finding these allies, however, was a challenge. After being rejected multiple times by traditional industry players who doubted the concept, Borouge International recognized the opportunity and invested in the vision.
Working with suppliers like Infinium – a leading producer of commercial-scale e-Naphtha – the brand was able to move from concept to commercial reality far more quickly than would otherwise have been possible.
“We didn't have a massive business case – we just had a few slides, immense enthusiasm, and a big dream”, continued Jean-Philippe. “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 wild prototype to commercial-scale production is incredibly fast for the chemical and footwear industries.”
Moving forward, On aims to replace traditional EVA midsole units in other styles across its product portfolio with innovative alternatives like CleanCloud. The Cloud X 5 launched July 16, 2026. AT
www.on.com
www.infiniumco.com
www.borougeinternational.com