Explore more inspiring stories at www.sonnenfreunde.de – your link to a brighter future. Share your solar journey with us using #IchBinSonnenfreund for a chance to be featured . ☀️ The Fraunhofer Institute is developing windows that generate electricity while maintaining visibility. Early prototypes power interior sensors and lights. "Soon, every building with glass can be a mini power plant," predicts Dr. Anna Kruber, lead researcher.