Back to grid

Made from carbon emissions – The CleanCloud™ story

From early setbacks to eureka moments, emissions-eating bacteria to action-movie moments. The story of how we made a shoe from carbon emissions has it all.


The origin story of CleanCloud™ technology is worthy of science fiction. Only it’s science fact. 


CleanCloud™ turns carbon emissions into performance products. We’re flipping the idea that carbon emissions are waste, and instead looking at these harmful gases as a resource. And that’s how this story began, when On’s innovation team asked: “What if, instead of an environmental problem, carbon emissions could be part of an environmental solution?” 


“What if…” starts a lot of sentences at On. And in 2018 we started asking the “what if” questions that led to CleanCloud™. 


The project marks an important step in On’s journey to move away from using fossil-based materials. But by its very nature, true innovation means navigating uncharted waters. And there were some rough seas along the way.


Finding a way



“It has been emotional – the most intense project I ever worked on,” said Nils Altrogge, On’s Head of Technology Innovation. “There were times when I had tears in my eyes, I was so frustrated,” he admits. “But we never stopped believing we could find solutions. The next day, I would wake up, everything would look better, and we’d go again.”


For Nils, these challenges are part of the day job. “People often want to have a solution to work on before you start a project,” he explained. “At On, we prefer to work towards a goal and discover along the way. This is the only way to be a pioneer – to be bold, take risks and develop solutions on the go.”


This is exactly how the team went about creating the CleanCloud™ project, which began when On Co-Founder Caspar Coppetti suggested they explore a collaboration with a company creating fuels from carbon dioxide. 


On was already on a journey to move away from fossil resources – the starting point for almost all plastics. With Cyclon, On’s subscription service that offers a fully recyclable shoe, the shoe is made using bio-based materials. The question was, what other raw materials could the team explore? Every material in the world is made from carbon atoms, so Nils figured there was no reason taking them from carbon emissions wouldn’t work. 


He pitched the idea to Jean-Philippe Romain, Head of Materials Science at On. His response was:


"This is wild, but... let's do it.”


The team began working with the fuels company Caspar had told them about. But after a year working together to build a new manufacturing unit, there was a problem. 


“All we could get was a small bottle of material to work with. This approach was just never going to be scalable. The project was basically dead at that point. But we decided the idea was too good to be killed, that there had to be another way.”


Building the team



Continuing the project meant starting from scratch. The team are not chemistry experts. But they dedicated themselves to gaining the knowledge needed to find a solution – or at least to have informed conversations with people who could point them in the right direction. 


It was at this point that On invited a group of biochemists, from both industry and academia, to come and discuss the challenge. They drew up all the possible solutions on a whiteboard. 


“There were some incredible proposals,” Nils recalled. “One was to use synthetic biology to program bacteria, so they could convert CO2 to produce exactly the material we want. This sounded incredible, but it might only be feasible in around 50 years. Needless to say, we work to shorter timelines than that.


“Our mantra is: discover, apply, scale, do it fast. It was at this point we realized that, if we were to use carbon emissions as a raw material in a scalable way, we’d need a proper supply chain. But such a supply chain didn’t exist. To make the dream a reality, we’d need to pioneer this new supply chain ourselves.”


Undeterred, the On team began driving the creation of a new biochemical supply chain. They couldn’t do it alone, so they went looking for the right partners.


In his research, Nils came across LanzaTech, a company specialized in carbon recycling. LanzaTech captures concentrated carbon emissions from industrial sources before they can be emitted into the atmosphere. They then use a special strain of bacteria first identified in rabbit droppings (yes, rabbit droppings) to turn this carbon waste into ethanol through fermentation. In basic terms, the fermentation process is similar to the one you’d find in a traditional brewery, only instead of using sugar and yeast to create beer, LanzaTech is converting emissions into fuels and chemicals. 


Excited by the prospect of making a shoe from carbon emissions, the Lanzatech team quickly came on board. This was a big step forward. As LanzaTech were able to derive ethanol from carbon emissions at scale, the team had overcome their original challenge. And other progress was happening too. 


Previous discussions with experts in the field had led to collaboration with Borealis, a leading provider of advanced, circular and renewable plastic solutions. 


EVA (ethylene vinyl acetate) is one of the most commonly used materials in the creation of performance products, specifically running shoe cushioning. Borealis were confident they would be able to use their lab-scale polymerization process to create EVA (ethylene vinyl acetate) from the carbon-emissions-based material. The On team was tantalizingly close to creating the necessary new supply chain. But there was one crucial link missing: the liquid ethanol produced by LanzaTech would need to be dehydrated to become ethylene gas, which is a monomer (the smallest building block in the production of plastic). And it wasn’t easy to bridge the gap.



When you picture a team trying to change the sporting goods industry with innovation, you might imagine shiny labs, complex presentations, passionate debates and treadmill testing. And that’s all part of it. But Nils is at pains to point out that true innovation, the creation of something that no-one else has ever done before, is more about resilience than science.


“I managed to get a list of potential partners to help us turn the ethanol into ethylene. And I just sat there, calling people all over the world. I spoke with labs in Russia, China, everywhere, to try and find the right one, receiving rejections over and over again. From a long list, finally, there were two candidates. And it turned out that one of them was already working with LanzaTech. This felt like a sign.”


That potential partner was Technip Energies (T.EN), who are now an integral part of the CleanCloud™ process. Specialists in converting ethanol to ethylene using dehydration, the belief was that T.EN’s technology could complete the supply chain. Being sure, however, would require the creation of a new full pilot plant, at significant investment. Thankfully, T.EN also bought into the potential of this moonshot innovation project. The pilot plant was soon ready to test whether the liquid ethylene gas processed from the carbon-emissions-derived ethanol was of the required purity for the team at Borealis to turn into high-performance EVA. 


After two months, the first ethylene sample arrived. This was a step in the process that Francois-Xavier Dosne (F-X to his friends), Head of Innovation Business Strategy at On,  remembers vividly. 


“I remember we first had a small sample [of ethylene] to test. It was in a small cylinder in a black suitcase. It looked like something that belonged to a Bond villain. And this is highly explosive material, so in a way it’s a bit like a bomb. You can only transport small quantities at a time. 


“It was a tense part of the process because we really needed that the material was 100% pure. If you plug it into the process and the chemical reaction isn’t exactly what we want, then there’s a real risk of an explosion. When the tests showed the quality was what we were hoping for, it was a massive moment for the project – we could now keep moving forward.” 


The moment of truth



Now the team at Borealis had confirmed the ethylene was pure enough for the production of EVA, the production process could begin. As this was the first time their facility had been involved in making material for shoes, the Borealis team worked closely with On’s materials expert Jean-Philippe Romain on the next steps. After 10 weeks of dedicating part of their facility to producing the EVA, stopping the process only when the equipment needed to cool, the resulting small pellets of plastic represented a world-first: this was the first material of its kind made from carbon emissions.


With every step of this new supply chain project in place, the On team could now focus on making their dream of a shoe made from carbon emissions become reality. They traveled to our production facilities in Vietnam with a small, one-of-a-kind (and therefore extremely valuable) sample of the EVA to try and do something never done before – create a performance running cushioning out of carbon emissions. 


“I have had more relaxed trips,” smiles Nils. “We were aware we had a very special material with us in our hand luggage. It didn’t help the nerves at airport security that the EVA pellets look like diamonds. It was a long journey from Switzerland to Asia, but I don’t think I slept at all. We’d come so far to get to this point – it was nerve-wracking, but also super exciting.”


At the Yusung production facility in Vietnam, the teams shared Nils’ excitement. Even for these specialists in shoe-cushioning, this was a first. The Yusung team had prepared for months to ensure these initial tests – the production of just five pairs of shoes – would go smoothly. 


After testing in the on-site lab, the carbon-emissions based pellets were halved for mixing into different “recipes” with elements such as blowing and crosslinking agents, which are needed to foam the EVA. This gave the team only two attempts at achieving the desired result. 


Having loaded the material into the machine that creates the midsoles (the units of CloudTec® cushioning), the team faced a nervous wait for the results. A tense silence descended. But it didn’t last long. 


“Seeing the first CleanCloud™ midsole pop out of the machine triggered euphoria,” Nils recalls. “It was an emotional moment, there weren’t many dry eyes. Not only did it look like a midsole, but the quality was really, really high.”


The midsole then went onto a conveyor belt for a curing process with other non-CleanCloud™ midsoles, leading the team to dash around the facility following it, not daring to take their eyes off this first precious proof of concept. 


Towards a fossil-free future



After the curing process, the midsoles were taken to our partners at Zucca to be assembled into the Cloudprime – the first-ever CleanCloud™ shoe, with every element considered for its environmental impact. A proof of concept, the Cloudprime combines some of the most advanced and most sustainable materials in the world. 


Like the midsole, the polyester used in the upper is made from carbon emissions – the result of a collaboration with French start-up Fairbrics. Engineered for running on the road, the hidden Speedboard® responsible for the Cloudprime’s agile feel is made using material derived from castor beans. The shoe’s outsole is the result of another innovation partnership with chemicals start-up Novoloop, which is making high-performance material made from 32% post-consumer plastic waste. 


Still in development, and not available for purchase (at least not yet), the first few pairs of the Cloudprime is now being put through its paces by elite athlete testers including holder of the Swiss marathon record, Tadesse Abraham, and German 1500m specialist Fabiane Meyer.


“I really enjoyed running in the CleanCloud™ shoe, especially when I heard it’s made from carbon emissions,” Fabiane says. “I thought that it’s maybe not possible that the shoe is as good as the other On shoes because of the sustainable material. But it is, it feels comfortable, gives you enough support and makes running effortless. It is a big step in the right direction for our future.” 



For the team behind the project, such feedback validates the decisions taken to push ahead with the project when others might have turned back. They’re also clear that the ride isn’t over yet.


“Holding the first-ever shoe made of carbon emissions in my hands is a huge milestone – not only for On, but for the whole sports industry”, says Caspar Coppetti.


“Five years ago, this was barely a dream. Imagine what can happen in the future as we unlock the potential of alternative carbon sources with further research and in collaboration with the best partners.


“Our ambition is to bring the CleanCloud™ technology to as many consumers as possible in the near future.”


Nils is also quick to emphasize that the project is far from over: 


“Making five pairs of the Cloudprime was an incredible story. But we’re thinking about five million – and more. There will be more challenges along the way, but the CleanCloud™ project has shown us that, by constantly questioning the status quo, refusing to give up, and having the right team with the right mindset, there are no limits.”


“We’re dreaming of decarbonizing our industry. And this is just the beginning.”