After graduating as Master of Mechanical Engineering and receiving a PhD in Chemical Engineering at the University of  Karlsruhe (TH), Stefan Hoffmann joined the Gas Turbine Development Team of Siemens AG in Mülheim an der Ruhr in 1994. In 2004 he graduated as International Executive MBA in the global OneMBA program at Kenan-Flagler Business School, University of North Carolina, Chapel Hill, USA.

In 2005, Hoffmann left his position as Siemens' Head of Gas Turbine Component Engineering to become SVP, R&D at Viessmann in Allendorf (Eder). In 2009 he became GM of Köb Holzheizsysteme GmbH in Wolfurt, AT and Mawera Holzfeuerungsanlagen GmbH in Hard, AT.

Since 2012, Dr. Hoffmann leads the Viessmann Academy, Viessmann's corporate training centre for employees and customers.