Pr. Dr. Ing. R. Bennacer, is an Engineer in Mechanical field (1989), and PhD thesis at Pierre et Marie Curie University in 1993. Professor (Exceptional National Class) in the prestigious school Ecole Normale Superieure (Paris-Saclay). Was Dean of Civil/Environmental department); Director of the Innovation-Prospective and Research division of the ECAM-EPMI. Actually Coordinate international Affairs and international joint Ph.D, at Univ Paris-Saclay. His present research activity is within the LMT laboratory. It covers the building material for energy applications or on durability aspect, renewable and energy system. The expertise couple the direct multi-scales numerical simulation and the analytical or reduction approach in order to identify the instabilities and similarity controlling parameters. He published more than 10 book chapters and more than 200 referenced international journals.