Former Bewag architect, Hans Heinrich Müller’s industrial buildings are important monuments in Berlin’s urban structure, although their original function is no longer relevant in today’s world. Their conversion and reuse has become an important and challenging task. This publication documents the Hans-Heinrich-Müller-Prize competition issued by Berlin energy supplier, the Bewag in 2004 for concepts for the revitalisation of transformer station Wilhelmsruh. All competition entries are included, as well as an overall picture of various possible concepts for reuse.