He studied Applied Physics at the Technical University of Darmstadt, Germany, and worked since 1984 as a scientist at Oeko-Institut where he coordinated its Energy & Climate Division in Darmstadt until 2010. After that he focused on international activities and projects on sustainable biomass. In early 2012 he founded (together with others) IINAS and works there as its Scientific Director. His expertise is in material flow and life-cycle analysis of energy, material and transport systems, developing sustainability scenarios with respective modeling and data bases.

Since 2019 he is Task Leader of IEA Bioenergy Task 40 (Deployment of biobased value chains), Co-Leader of IEA Bioenergy Task 45 (Climate and Sustainability Effects of Bioenergy within the broader Bioeconomy) and leads the Task Force of Sustainability’s Environment Subgroup of the Global Bioenergy Partnership.

Besides his scientific work he is a Reiki Master, practices QiGong and likes Nordic Skating, and riding trains.