The Control of energy consumption by sensor networks and the maximization of the sensor network lifetime are the most fundamental issues. Due to the variety of protocols dedicated to the different sensor’s layers and the difficulty of a real network deployment, designers need some mechanisms and tools to validate the energy consumption and to observe its impact on the network’s lifetime before deployment. In this context, we have proposed a modeling approach considering the global behavior of a sensor network and allowing the estimation of the network’s energy consumption. This approach is based on the concept of components oriented modeling and the expressiveness of Colored Petri Nets (CP-NET). Thus, the global model representing sensor behavior is obtained by interfacing different models each one representing the behavior of a particular component of the sensor. In this work, our interest was firstly focused on the radio because it’s the most energy consumer. When observing the node functioning, we show that the radio behavior is mainly controlled by the MAC component. Therefore, we were also interested in MAC component. The generated model has been used to estimate the energy consumption and to evaluate the network lifetime. Adopting the oriented components modeling approach, we may obtain two global models, where only MAC protocol change. Obtained models, representing the behavior of mostly used MAC protocols, allow comparing the impact of these two protocols on the network’s global behavior and particularly on its lifetime.