Nowadays, the use of mobile applications and terminals faces fundamental challenges related to energy constraint. This is due to the limited battery lifetime as compared to the increasing hardware evolution. Video streaming is one of the most energy consuming applications in a mobile system because of its intensive use of bandwidth, memory and processing power. In this work, we aim to propose a methodology for building and validating a high level global power consumption model including a hardware and software elements. Our approach is based on exploiting the interactions between power consumption sub-models of standalone systems in the perspective to build more accurate global model. The interactions are studied within the exclusive context of video streaming applications that are one of the most used mobile applications.