•  Is there any free lunch for EH WSNs? •  Challenge: Energy source is there but … … it is unreliable, erratic and intermittent •  Need for intelligent designs –  Adaptive energy mangement –  Transmission vs Storage vs Scavenger Size

era are still unable to provide the reliability needed by the industrial world, particularly in terms of the wireless operation that pervasive deployments demand. While industrial wireless performance has achieved an acceptable degree in communi-cations, it is no easy task to determine an efficient energy-dimensioning of the device in order to meet the application requirements. This is especially true in the face of the uncertainty inherent in energy harvesting. Thus, it is of utmost importance to model and dimension the energy consumption of IoT applications at the pre-deployment or pre-production stages, especially when considering critical factors such as reduced cost, life-time, and available energy. This paper presents a comprehensive model for the power consumption of wireless sensor nodes. The model takes a system-level perspective to account for all energy expenditures: commu-nications, acquisition and processing. Furthermore, it is based only on parameters that can be empirically quantified once the platform (i.e., technology) and the application (i.e., operating conditions) are defined. This results in a new framework for studying and analyzing the energy life-cycles in applications, and it is suitable for determining in advance the specific weight of application parameters, as well as for understanding the tolerance margins and trade-offs in the system. Index Terms—Low power models, smart sensors, networkable sensors, wireless sensor networks, sensor system networks, sensor system integration. I.