OpenOffice is an experimental building for the Zeche Zollverein site in Essen / Germany. The aim is to develp an energetically autonomous and infrastructurally independent building. Tools to achieve energetic autonomy: - economic building planning with utilization of active and passive methods to improve energy efficiency. - optimization of the building skin - concerning materials and buildign systems - photovoltaic energy gain thourh solar foil - thermal solar gains thourh solar ripp collektor - fuel cells to generate electricity - the thermal redundance will be used for heating. Tools to achieve supply autonomy: - collection and filtration of rain water via the roof-scape - installation of a decentralized vacuum deposit system The building will state an example, how modular light-weight building methods, can establish sustainable buildings.