Mechanical Engineer with a PhD (1988), MSc (1985) in thermal sciences from Georgia Institute of Technology, and BSc (1984) in energy from Michigan Technological University. Leader of Group Energy Conservation at IERSD-NOA since 1995. Research interests in the areas of energy conservation, high performing buildings and decarbonization of the built environment, sustainability assessment of buildings-neighborhoods-cities, solar thermal and cooling applications, building energy audits-diagnosis and retrofitting, environmental impact of buildings, indoor environment, thermal simulations, solar air-conditioning. Instrumental in the development of the technical guidelines and the national regulation on the energy performance of buildings (KENAK) for EPBD transposition in Greece. Editorial Board member in Energy & Buildings. ASHRAE Vice President (2011-2013) and Member of the ASHRAE Board of Directors as Director & Regional Chair Region XIV – Europe (2017-2020) and Director At Large (2007-2010); Chartered Mechanical Engineer and Member of the Technical Chamber of Greece; EUR ING; Fellow ASME; Fellow ASHRAE.