Hartmut Bossel (born 3 March 1935) is a German environmental scientist and systems scientist. Bossel was a professor of environmental systems analysis and director of the Scientific Center for Environmental Systems Research and Environmental Systems Analysis Group at the University of Kassel, Germany, until his retirement in 1997. Bossel and co-author Florentin Krause are credited with coining the term Energiewende, used to describe the change in German energy policy from 2010 onwards, in 1980.