Hans-Josef Zimmer holds the position of Chief Technical Officer for EnBW Energie Baden Württemberg AG and Chairman-Supervisory Board at terranets bw GmbH and Chairman-Supervisory Board of TransnetBW GmbH (both are subsidiaries of EnBW Energie Baden Württemberg AG). Dr. Zimmer is also on the board of Vorarlberger Illwerke AG and EnBW Kernkraft GmbH (former Chairman-Management Board).

In his past career Dr. Zimmer held the position of Chairman for EnBW Regional AG and Member-Management Board at EnBW Erneuerbare und Konventionelle Erzeugung AG.

Hans-Josef Zimmer received an undergraduate degree from RWTH Aachen University and a doctorate from Karlsruher Institut für Technologie.