“I can be persistently stubborn”

How Roland Brüniger invented his self-heating soles Chili-Feet with courage, persistence and idealism and why he is not interested in lucrative takeover offers from enterprises.

Claudia Bardola

As a Graubünden native who was washed down to the lowlands, you would expect me to be largely resistent to the cold. And yet, previously, I was plagued by icicle toes from autumn onwards. For many years, I wracked my brains for ways to solve this problem sustainably, without using electricity or chemicals. As an engineer, I simply didn’t want to believe that nowhere in the world had a material been invented that allowed energy to be converted to heat while walking.


Initial investigations showed that this should be possible with polyurethane as a source material. So I set three development teams to work on the development, two from industry and one from a university environment. After numerous experiments, the academic team forfeited. The professor responsible assured me that my plan was extremely ambitious and on the verge of feasibility. Did this put a damper on things? No way, it spurred me on! I’ve always agreed with Walt Disney: all our dreams can come true, if we have the courage to pursue them. In addition, I can be persistently stubborn, as my wife occasionally likes to rub in my face.


Finally, a team from Vorarlberg hit the bull’s eye. They delivered the basic material for Chili-Feet as we sell them today. But two weeks before the market launch disaster struck: the machine that a Swiss laminating company was using to stick the upper and lower material for the soles together was obviously not intended for large quantities. We had to improve 20,000 soles by hand. Sad but true: our search for an alternative failed to bear fruit anywhere in Switzerland. That’s why Chili-Feet are now laminated in South Germany.


Despite my invention I wouldn’t call myself an inventor. The Chili-Feet are simply a solution to a problem that had been bothering me for a while. As far as finances are concerned, I always say: we have financial accounting but no payroll accounting. I wisely don’t make a note of the time I invest in the project.


“Despite my invention I wouldn’t call myself an inventor”

This is only possible because I earn my crust through my engineering office for technical systems. In addition, Wafe Technology, which sells Chili-Feet, is a true family company. My wife takes care of accounting, my daughter is responsible for social media and logistics, and my son is in charge of IT. In addition, our house is just 300 metres away from the company. Combining work and family has always been high up on my agenda for life. For me, that’s true luxury.


The functional principle of the soles is actually quite simple: the material converts some of its deformation energy to heat in a process known as dissipation. The effect: a temperature increase of up to 10 degrees. But when it comes to the material, the soles are a complex, high-tech product. This is exactly the reason that I didn’t have them patented. For this, we would have to reveal the recipe and it would thus be possible to copy us. A patent dispute would be the end of us.


1/5 “Keep it simple” is Brüniger’s motto when working with his company. For this reason, he does not provide the heated insoles in different sizes – they must be cut to size by the future wearers themselves. This ensures efficiency in production as well as logistics.

2/5 Idealist Roland Brüniger works passionately on his project and politely declines takeover bids from corporate groups running into the billions.

3/5 A host of investigations, experts and material tests were necessary before the ideal source material for the Chili-Feet was found.

4/5 At Brüniger, the whole family is involved: Son Andreas takes care of IT, his wife Evelyn does the accounts. Daughter Patricia has just earned herself a language stay abroad through her work at the company.

5/5 With Chili-Feet, Brüniger has also solved a problem within the family: “My wife and I always used to have cold feet come the autumn. This is now a thing of the past.”

1/5 “Keep it simple” is Brüniger’s motto when working with his company. For this reason, he does not provide the heated insoles in different sizes – they must be cut to size by the future wearers themselves. This ensures efficiency in production as well as logistics.

I financed the entire project through private means. That guarantees me independence – one of my basic instincts. I rejected the offer of a takeover from a multi-million group without even getting into concrete negotiations. After all, my entire heart and soul went into the Chili-Feet and I want to watch this little seedling grow into a strong tree.


Although my work days are long and intensive – work-life balance is extremely important to me. I achieve balance among other things through cycling, swimming and playing tennis, spending time with my family and meditating. The latter is a legacy from my travels to India and Nepal during my youth. Today, it grounds me.

Roland Brüniger

Roland Brüniger is not just an inventor, but also the owner and managing director of R. Brüniger AG, an engineering office for technical systems. Due to a specific research mandate, he frequently comes into contact with various innovative technologies. Brüniger is married, has two children and lives and works in Ottenbach in the Zurich region.


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