Hinrich Uellendahl (née Hartmann) came to Flensburg for the first time after graduating from high school in 1986, when he first did his two-year community service at the Deaconess Institute and then completed a three-year training course to become a nurse. He then began studying technical environmental protection at the Technical University of Berlin in 1992, graduating in 1998 with a degree in engineering. After spending time abroad at the Technical University of Denmark (DTU) as part of his diploma thesis, he continued his work at the DTU in the biotechnology and process engineering department after completing his studies, and obtained his doctorate in the field of biogas technology there in 2003. His PhD thesis is entitled "Anaerobic digestion of the organic fraction of municipal waste with recirculation of process water".

He continued research and development in the field of converting biomass into biogas and other fuels from 2003 to 2008 as an assistant professor and later as an associate professor at the DTU. In 2008, he moved to Aalborg University (AAU), Copenhagen campus, as an associate professor in the newly founded "Sustainable Biotechnology" research group. The focus here was on the development of sustainable concepts for the use of biomass, especially organic residues, for the production of fuels and biomass-based chemicals. In this context, Prof. Uellendahl acquired and led numerous research projects and taught bioprocess engineering.

In March 2019, Hinrich Uellendahl returned to Flensburg as a professor in the Department of Mechanical Engineering, Process Engineering and Maritime Technologies at Flensburg University of Applied Sciences. Here he continues his research and teaching in the field of sustainable energetic and material biomass use. Accordingly, his expertise in the ZNES is the extent to which sustainable energetic biomass use can be coupled with other renewable energy sources and optimized.

Prof. Dr. Uellendahl is also spokesperson for the Competence Center for Renewable Energies and Climate Protection in Schleswig-Holstein (EEK.SH).