## 1 Introduction  
Recent studies on energy efficiency are moving towards more strategic energy management practices that highlight the need for an information system able to set goals, track performance and communicate results. Some countries are developing their electric power grids in the direction of smart grids that combine information technology, communication technology, computer technology with generation, transmission and distribution power systems [1]. It is quite clear that the development of the smart grid is a priority because it represents an opportunity to obtain a supply chain of electricity that is secure and reliable, efficient, economical, clean, green, flexible and integrated. In this scenario, ICT technologies are becoming the core of the smart grid vision and are necessary, for example, to improve the problems of restoring power outages or facilitate the integration of the renewable energy sources. All that leads to a change in network design principles and in network operation and procedures and pushes towards the decomposition of the problem in three different areas: smart generation, smart grid and smart customer [2]. The problem is very complex and when discussing about a smart vision for energy management it is necessary to refer not only the physical network [3] but also to the adoption of fast analysis tools, wide area monitoring, measurement and control (WAMPAC). Moreover, the efficient management of energy sources is also a crucial problem for small-medium-large sized industrial companies and residential applications [4]. The smart grid is changing the energy market and for large companies the availability of different providers that compete in the energy market is a good news which should theoretically lead to cost savings and advantage of energy quality. However, the single company is rarely able to follow the trend of the energy market and usually it does not have the information necessary to operate an energy efficiency improvement in almost real-time, compared to its actual needs. Typically the problem is solved by evaluating, for example, every couple of years the new offers on the market and deciding to change energy supplier. This approach is static and does not allow any type of optimization due to the different operating conditions of the plant, which normally shows a variable energy need in the same day and at different times of the year. Also, in the big companies this approach can be very expensive. In brief, it is difficult for a company to control its energy balance and a new approach is needed to provide advanced information, maybe in real-time, to stakeholders in order to facilitate the business plan. Information technology comes powerfully into play to compensate the current lack of information and intelligence of electrical networks, and efficiently address the new technological and organizational challenges. In this paper we describe an application in which the technology helps to monitor power system dynamics in real time within the ST Microelectronics industrial site of Catania from remote locations. The purpose of this on-line analysis tool is to create a system with the aim of acquiring information to determine the behavior of the energy system and to better support the future management decisions. To this purpose, the system is designed to capture data from electrical substations in real-time, and to transfer them to the control system which has to analyze the information, also using business intelligence methods. In this way information on the energy usage inside the plant will be available and analystswill be able to perform any kind of data computation in order to better set the plant or drive the energy purchase decisions. The solution permits a self-awareness of the system operation state that will improve operations and control strategies. The technological solution we adopted is based on a Wireless Sensor Networks (WSNs) communication infrastructure.