Funding for this research was provided by:
Karlsruher Institut für Technologie (Energy Scenario School)
Text and Data Mining valid from 2018-07-09
Received: 18 December 2017
Accepted: 6 June 2018
First Online: 9 July 2018
Consent for publication
: Not applicable. No personal data used.
: The author declares that she has no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.