In October, a team of 45 students from RWTH Aachen University and FH Aachen, Germany, will take part in the Bridgestone World Solar Challenge 2019 in Australia for the second time with a new solar-powered racing car. In what is probably the toughest solar race in the world, teams from all over the world will compete to overcome the 3,000-kilometre stretch from Darwin to Adelaide as the fastest with homemade vehicles. Ultra-light cars with good aerodynamics and energy efficiency have the best chances for a good result in the solar race. For two years, the Sonnenwagen team worked on the construction of their new racer, paying particular attention to streamlined structures, smooth surfaces and lightweight materials. Innovative materials from Covestro, the main sponsor of this year's project, are also at the start. Covestro is using the project to test various materials under the harsh climatic conditions of the track. The climatic conditions mainly influence the clear coat. A two-layer polyurethane car refinish paint system from PPG is used on the sunbed car. It gives the body a smooth, high-gloss surface and resists the harsh climatic conditions. It is also well protected against scratching. The special feature here is the coating formulation with a biobased hardener from Covestro. 70 percent of its carbon content comes from biomass, which reduces the ecological footprint by around 30 percent.