How can we make the mobility of the future as sustainable as possible? A group of highly motivated students at RWTH Aachen University and Aachen University of Applied Sciences posed this question and, to find out, dedicated their efforts to an ambitious project: the development of a solar-powered electric car for what is likely to be the toughest solar car race in the world, the World Solar Challenge 2017 from October 8 to 15 in Australia. To make their idea a reality, the approximately 45 junior researchers established the “Sonnenwagen Aachen e.V.” association, with the support of their professors.

Covestro, a leading global supplier of innovative and sustainable material solutions, shares the students’ enthusiasm and wants to join forces with them to push existing boundaries and make the project a success. The company has cultivated a long-term partnership with the distinguished university and is supporting the “Sonnenwagen” (German for “solar car”) project as both a material and technical service provider and Gold Sponsor. The two partners recently signed a cooperation agreement for the project.

Partnership for solar mobility
“As sustainability is part of our strategy, we support this ambitious project, in which young researchers want to show that innovative and sustainable mobility concepts are already possible today,” says Dr. Markus Steilemann, Board Member for Innovation and Chief Commercial Officer of Covestro. “Solar mobility can make a key contribution to protecting the climate and conserving fossil resources. With our developments and this project partnership, we want to demonstrate our commitment to innovation and sustainability, but also to supporting junior talents.”

Hendrik Löbberding, First Chairman of Team Sonnenwagen, welcomes the new partner: “We are very grateful for Covestro’s support and will benefit above all from its superior competence in materials.” The Leverkusen-based company already has gained extensive experience using its innovative materials for solar mobility: As an official partner of the Solar Impulse project, it made a significant contribution to the success of the first manned flight around the globe in an aircraft powered exclusively by solar energy.

Road test: automotive coating with bio-based hardener

Covestro wants to take advantage of the Sonnenwagen project to test various materials under the harsh climate conditions prevailing along the race’s route: temperatures of up to 45 degrees Celsius, high UV radiation and a high air dust content are typical there in October. The most important product application is a three-layer polyurethane coating from PPG, a leading global manufacturer of automotive coatings. The coating is particularly suited to application on body parts made of carbon fiber composites.

The climate conditions have a significant impact on the top clearcoat. It is formulated with the bio-based hardener Desmodur® eco N 7300 from Covestro, 70 percent of whose carbon content is sourced from biomass.

The Sonnenwagen further incorporates polyurethane and polycarbonate materials from Covestro, which contribute to the lightweight and aerodynamic design of the solar car.

Acid test for solar cars
The World Solar Challenge is considered to be the toughest solar race on earth and celebrates its 30th anniversary this year. Teams from all over the world compete every two years in their homemade vehicles to win the 3,000 kilometer race from Darwin to Adelaide – without using one drop of fuel.

The Sonnenwagen from Aachen will be the only German car going to the starting line in the Challenger Class this year. The team is very optimistic about its chances in the race: “We already have experience with zero-emission mobility and feel well-equipped to take part in the competition with the roughly 40 other teams from five continents,” says Hendrik Löbberding of Sonnenwagen Aachen team.

Two members of the association raced an electric car in, and won, the e-CROSS Germany, a four-day, climate-neutral rally through North Rhine-Westphalia. One month prior, the Sonnenwagen members accompanied a team from Bochum in the European Solar Challenge 2016, a 24-hour race in solar cars.