1. a Department of Psychology , Albert-Ludwigs-Universität Freiburg , Engelbergerstraße 41, D-79085, Freiburg, Germany
2. b Department of Intelligent Energy Systems , Fraunhofer Institute for Solar Energy Systems , Heidenhofstraße 2, 79110, Freiburg, Germany
3. c Department of Psychology , Johannes Gutenberg-Universität Mainz , Wallstraße 3, D-55099, Mainz, Germany