Researcher and teacher for 35 years on energy conservation and other solutions to environmental problems, most of the time at DTU. Background includes practical education as mechanics 1955, MS in Engineering 1963, PhD in Applied Physics 1967. Post Doctoral Fellow at Catholic University, Washington DC, USA 1969-71. Research Fellow at Dartmouth College, New Hampshire, USA 1973-74. Since 1972 work has been around energy consumption and how to reduce it with environmental as well as human benefits. Technological options have been investigated in specific micro cases. Most efforts, however, has been, through energy planning and scenario analyses, to demonstrate potentials for energy conservation on a macro level, for instance in Denmark, Scandinavia and Europe. Results have been disseminated internationally through numerous articles, books, scientific conferences, seminars, talks and advises to governments, UNDP, NGOs, University faculties, etc. around the world. Have been member of various energy related Danish government committees and councils. Widespread international professional network maintained from the dawn of the environmental awareness in the 1970s. Member of the Balaton Group, an international environmental organization of ca. 200 scientists and managers.