“My motto is: 100% dedication for 100% renewable energy. That’s why I am commmitted to that in many fields; because it’s not enough to install systems. We need creative ideas!” It started with an orange tie and the imprint “100% renewable”: With this statement, back in 2007 very provocative, Matthias Willenbacher initiated the 100% renewable …

Sonja Wiesner has more than 20 years of professional experience as a manager in marketing and corporate communications, including political agenda-setting. She spent approximately ten years at the RWTH Aachen Campus, Europe’s largest technology campus. Since April 2025, she has served as Chief Communication Officer alongside Matthias Willenbacher in the areas of marketing, corporate communications, …