1. Chair of Renewable and Sustainable Energy Systems, Technical University of Munich, Arcisstraße 21, 80333 Munich, Germany
2. Institute of Techno-Economic Systems Analysis (IEK-3), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany
3. Lehrstuhl für Brennstoffzellen, RWTH Aachen, c/o Techno-Ökonomische Systemanalyse (IEK-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
4. Institute of Energy Economics and Rational Energy Use (IER), University of Stuttgart, 70565 Stuttgart, Germany