Sept 1989 - Dec 1991, Fritz Haug AG, St. Gallen Switzerland: testing engineer:dry running compressors for special applications and concrete cutting saws, intensive focus on mechanical, pneumatic and hydraulic know how and testing regime development,Aug 1992-March 1995, Anton Rüf Gerätebau GmbH, production manager:Milling and separating-machines for biological-waste-fractions and waste oil-conditioning-plants;April 1995- Dec 1996, Vogel & Müller GMBH, production/project manager and sales:Closed-composting-systems of V&M, combined with biological waste milling technologies;Feb 1997- May 2001, MAWER GmbH & CO KG, engineering manager of mechanical construction (screw feeders, conveyors, crushers), from 1998 also the lead of the project management department;Producer of wooden chip firing Plants from 100 kW up to 13.000 kW; Water, Steam or thermal Oil Boilers (first CHP applications with thermal Oil),June 2000-May 2003, Bug-Alu Technic UK, project manager,Producer of high end curtain walling in the international market;June 2003-July 2007, Wirkungsgrad GmbH, chief production officer; Quality officer ISO 9001;Energy contractor renewable sources; CHP power plants, crude oil engines operated with used cooking oil (overall power 6.000 kWh); several gas, pellets and wooden chip boilers for heating applications from 350 to 700 kW; thereof some combined with solar panels;Aug 2007- Nov 2011, barvon curtain wall gmbh, project manager, Quality officer ISO 9001;High-end curtain wall applications in major building projects in the UK;2012 first consultant-engineering services, energy efficiency of processes and buildingsMarch 2012-July 2014, entec Biogas GmbH, chief production officer; Quality officer ISO 9001; head of operationsLeading producer of Anaerobic Digestion Plants in the international market, UK, US, DE, FR,Since 2014 self-employed Consultant engineer and business consultant;