Hello Philipp. While I agree with @ludwig.huelk , I am going to be a little more conciliatory. Table 1 (page 5–6), for instance, describes the data sources you used for the electricity sector. They span NASA MERRA-2 satellite data under public domain (courtesy of the US government) to OpenStreetMap which is copyleft ODbL. While the legal status for other sources, say that obtained from the OPSD database, is “gray” at best. So it is not possible to relicense the entire dataset under one overarching compliant license.
In theory, it would be possible to split up the spreadsheet into individual spreadsheets or CSV files, each with its own license (or no license) and suitable metadata. That is probably where things could be heading, but the question of internal consistency remains open. That was a design goal for the OPSD project (hopefully they will secure more funding).
The larger problem we collectively face will not be solved until the European Commission mandates the use of permissive licenses or public domain dedications and we and/or the Commission develop an ontology and related standards for the energy sector.
In the background is the question as to whether much or most of this data is indeed copyrightable. Hopefully the Commission can clarify this matter in due course.
Notwithstanding, DIW could release the PDF documentation under a Creative Commons license. Perhaps you should explore that option with your board? I know it is not common practice for institutional reports to be open licensed.
The full references are repeated below, because I just databased them.
Like Ludwig said, it looks like very useful work. Best, Robbie.
Kunz, Friedrich, Jens Weibezahn, Philip Hauser, Sina Heidari, Wolf-Peter Schill, Björn Felten, Mario Kendziorski, Matthias Zech, Jan Zepter, Christian von Hirschhausen, Dominik Möst, and Christoph Weber (27 December 2017). Reference data set: electricity, heat, and gas sector data for modeling the German system — Version 1.0.0. Berlin, Germany: DIW Berlin (Deutsches Institut für Wirtschaftsforschung). doi:10.5281/zenodo.1044463.
Kunz, Friedrich, Mario Kendziorski, Wolf-Peter Schill, Jens Weibezahn, Jan Zepter, Christian von Hirschhausen, Philipp Hauser, Matthias Zech, Dominik Möst, Sina Heidari, Björn Felten, and Christoph Weber (December 2017). Electricity, heat, and gas sector data for modeling the German system. Berlin, Germany: DIW Berlin (Deutsches Institut für Wirtschaftsforschung). ISSN 1861-1532.