Professor Vahrenholt holds a doctorate in chemistry and started his professional career at the Federal Environmental Agency in Berlin (responsible for the chemical industry) before joining the Hessian Ministry of the Environment. From 1984 until 1990 he served as state secretary for environment, from 1991 till 1997 as minister for energy and environment in the state of Hamburg.
In 1998 he entered the energy industry and until 2001 was a board member of Deutsche Shell, responsible for the renewable sector. In 2001 he was founding CEO of Germany’s third biggest wind turbine manufacturer REpower (now Senvion). From 2008 to 2012 he was CEO of RWE Innogy, the subsidiary for renewables of the electric power company RWE. In 2012 he was elected as chairman of the board of Deutsche Wildtier Stiftung, a German foundation for the preservation of wildlife in Germany.
In 1999 he was appointed as honorary professor of the department of chemistry at the University of Hamburg. He is also a member of the German National Academy of Science and Engineering in Berlin and member of the Senate of Fraunhofer-Gesellschaft in Munich and in 2014 joined the academic advisory council of the Global Warming Policy Foundation in London.
From 2001 until 2007 he was member of the sustainability advisory board to Chancellors Gerhard Schroeder and Angela Merkel.
He is author of several environmental books; the bestseller “Seveso ist überall” (“Seveso is everywhere”), published in 1978, was one of the most influential books for the green environmental movement in Germany and triggered a debate that led to a fundamental reorientation of the chemical industry towards sustainable development. His book “Die kalte Sonne” (“The neglected sun”), published in 2012, triggered a debate about the relevance of natural causes of climate change.