Team Sonnenwagen Aachen has successfully completed the 2026 iLumen European Solar Challenge. After 24 hours of racing at Circuit Zolder in Belgium, the current Sonnenwagen Æthon finished in fifth place, while its predecessor, Sonnenwagen Adelie, crossed the line in sixth. Together, the two solar cars completed 528 laps. Adelie had already secured pole position with the fastest lap in qualifying, while Æthon started the race from fifth place. A total of 26 solar cars from 22 teams representing 15 countries competed in Zolder. Four teams, including Team Sonnenwagen, entered two cars each.
The technically demanding circuit, with its tight corners and changes in elevation, challenged both the cars and the entire team. Throughout the 24 hours, the team had to balance speed and energy consumption while continually adapting its driving approach to the conditions on the track. Rain during the night and on Sunday morning made conditions even more difficult and led to several incidents across the field. At around 6 a.m., the rear of Adelie stepped out and the solar car tumbled over. No one was injured in the incident. The vehicle had to be removed from the track and taken to the team’s pit box. The team pulled together and was able to return Adelie to the race. Despite the time lost, Adelie went on to finish sixth.
“This race demanded everything from us,” says Nassim Lagrou, Team Manager of Team Sonnenwagen Aachen. “After the incident involving Adelie, it was clear to us that we would not give up. The team repaired the car and returned it to the track. We are very proud that both solar cars crossed the finish line in fifth and sixth place. At the same time, we are taking away important insights for our further development. The open dialogue with Covestro and its support with materials and expertise help us turn these insights into concrete improvements and continuously develop our vehicles.”
“Team Sonnenwagen delivered an outstanding performance, and we are pleased to have supported the team on this journey,” adds Monique Buch, Chief Commercial Officer at Covestro. “This achievement demonstrates what partnership can accomplish: The team contributes its deep understanding of the vehicles and its ideas, while Covestro brings its materials and application expertise. We are united by a passion and determination to drive progress by developing, testing and refining solutions together.”
A long-standing partnership with an eye on the future
This collaborative approach has developed over many years. Covestro has supported Team Sonnenwagen since it was founded in 2017 and has been its main sponsor and technology partner since 2018. In spring 2026, the partnership was extended for another two years. It goes far beyond financial support: with the shared objective of pushing boundaries and continuously developing the solar car, the team shares its requirements and experience from development, testing and racing. Covestro experts contribute their materials and application expertise. Together, the partners discuss technical challenges, test material solutions and refine them further.
The current Sonnenwagen Æthon demonstrates how this collaboration translates into specific applications. It incorporates more than ten different Covestro materials, including raw materials for chemically recycled foam in the driver’s seat, mass-balanced Vulkollan® for cushioning between the battery and the car body, and thermally conductive Makrolon® TC polycarbonate for the battery cell holders.
Following the finish in Zolder, attention is already turning to the next challenge. The insights gained from the European Solar Challenge will feed into the development of a new solar car, which the team plans to race at the Bridgestone World Solar Challenge in Australia in 2027. The goal is to build on its top finish from 2025 and, if possible, improve on it.