Partnership at Eye Level: How Covestro and Henkel Are Driving Sustainable Mobility with the Solar Car “Sonnenwagen”

With Covestro and Henkel, two companies are supporting the project that have been working together for years along shared value chains – particularly in the field of adhesive technologies. We spoke with Guido Naberfeld, Head of Sales and Market Development Mobility at Covestro and Project Sponsor of “Sonnenwagen”, and Sjoerd Dijkstra, Director Sustainability Strategy & Excellence at Henkel Adhesive Technologies, about their contributions to the solar car – and what becomes possible when forces are joined.

What motivated you to get involved in the “Sonnenwagen” project?

Guido Naberfeld (Covestro):
“The “Sonnenwagen” team impresses us time and again – with pioneering spirit, technical skill, and a clear vision for the mobility of tomorrow. For us, the project is much more than sponsorship: it’s a platform for collaborative development along the value chain. We contribute materials and expertise – and in return, we gain new perspectives and valuable insights. At the same time, our solutions must prove themselves under extreme conditions. That makes the “Sonnenwagen” a true benchmark for sustainable innovation.”

Sjoerd Dijkstra (Henkel):
“We’ve previously supported teams in the World Solar Challenge through our colleagues in Australia. So we know the pioneering spirit and forward-thinking engineering with which the “Sonnenwagen” team designs its solar race car – and that there’s a strong overlap between the team’s ideas and Henkel’s. Through our partnership, we want to support young talent and, of course, highlight the performance and sustainability of our solutions in demanding applications across key industrial sectors. We see the project as an ideal innovation platform for forward-looking adhesive technologies.”

Where exactly are your technologies used in the “Sonnenwagen”?

Guido Naberfeld:
“Our materials are used throughout the vehicle – this time, over ten products, more than ever before. For example, the driver’s seat is made from chemically recycled polyurethane foam – a material originally sourced from old car seats. We also use recycled material (mass-balanced) in the battery housing: elastomers that reliably dampen vibrations. The cockpit canopy and headlight covers are made from highly impact-resistant polycarbonate – lightweight, durable, and UV-resistant. There’s also thermally conductive polycarbonate in the battery cell holders, a sustainable coating that cures without energy-intensive processes, and several other applications.”

Sjoerd Dijkstra:
“For the current generation of the race car, we primarily supplied our proven Loctite and Teroson solutions. These products are used in the automotive industry and in various other industrial applications. They include structural adhesives, specialty adhesives for components like the motor, threadlockers, adhesive tapes, and hybrid adhesives for different mechanical parts. In the future, we also see great potential for using more advanced adhesive technologies. A key focus will be on products made from bio-based or recycled raw materials – an area where we’ve been working closely with Covestro, one of our most important global suppliers, for years. Our involvement essentially closes the loop – driving sustainability and performance forward together along the value chain.”

Why is collaboration along the value chain so crucial for sustainable mobility?

Guido Naberfeld:
“The direction is clear: the vehicles of the future must be lighter, more efficient, and circular. The planned EU End-of-Life Vehicle Regulation makes this visible on a regulatory level: in the future, 25% of plastics used in new vehicles must come from recycled materials – a quarter of that from end-of-life vehicles. Such goals can only be achieved together – through close collaboration among all partners along the entire value chain. When industry, academia, and other partners join forces, solutions emerge that can truly make a difference – for the market and the climate. That's the great thing about the “Sonnenwagen”: it also showcases this kind of collaboration. The fact that Henkel and we – and of course many other partners – are part of this project speaks for itself. And we’re already demonstrating the positive impact of such partnerships elsewhere: in the construction sector, Henkel uses our mass-balanced bio-based raw materials to develop more sustainable adhesive solutions for wooden components used in large buildings. That’s the spirit that will make the circular economy a reality in the mobility sector – and beyond!”

Sjoerd Dijkstra:
“Sustainability is the key performance criterion in the field of future mobility. This applies not only to the automotive industry but also to sectors like aviation and rail transport. The challenges in technological areas such as e-mobility and regulatory issues like reparability or recyclability are so significant that solutions can only be found through holistic collaboration between companies along the value chain. With our adhesives business, we operate at the interface between the chemical industry and application. We therefore work closely with both suppliers and manufacturers. That’s why we understand very well that sustainable designs can only be enabled through the combination of diverse expertise and the necessary transparency. The “Sonnenwagen” is an ideal model project for industrial cooperation. The experiences and insights we gain here, we aim to transfer into series vehicle production.
If students can build such incredibly innovative and performing cars, we as an industry should be inspired to also solve the sustainability challenges ahead.”