Demand Management and Wireless Sensor Networks in the Smart Grid

The operation principles and the components of the electrical power grid are recently undergoing a major renovation. This renovation has been triggered by several factors. First, the grid recently showed signs of resilience problems. For instance, at the beginning of 2000s, California and Eastern interconnection of the U.S. experienced two major blackouts which have caused large financial losses. The second factor to trigger the renovation of the grid is that in a near future, the imbalance between the growing demand and the diminishing fossil fuels, aging equipments, and lack of communications are foreseen to worsen the condition of the power grids. Growing demand is a result of growing population, as well as nations’ becoming more dependent on electricity based services. The third factor that triggers the renovation, is the inefficiency of the existing grid. In (Lightner et al., 2010), the authors present that in the U.S. only, 50% of the generation capacity is used 100% of the time, annually, while over 90% capacity is only required for 5% of the time where the figures are similar for other countries. Moreover, more than half of the produced energy is wasted due to generation and transmission related inefficiencies (Lui et al., 2010). This means that the operation of the power grid is rather inefficient. In addition to those resilience and efficiency related problems, high amount of GreenHouse Gases (GHG) emitted during the process of electricity generation need to be reduced as the Kyoto protocol is pressing the governments to reduce their emissions. The renovation targets to increase the penetration level of renewable energy resources, hence reduce the GHG emissions. Finally, the power grids are not well protected for malicious attacks and acts of terrorism. Physical components of the grid are easy to reach from outside and they can be compromised unless they are monitored well. To address the above mentioned problems, the U.S., Canada, the E.U. and China have recently initiated the smart grid implementations. Smart grid aims to integrate the opportunities that have become available with the advances in Information and Communications Technology (ICT) to the grid technologies in order to modernize the operation and the components of the grid (Massoud-Amin & Wollenberg, 2005). The basic building blocks of the smart grid can be listed as; the assets, sensors used to monitor those assets, the control logic that realizes the desired operational status and finally communication among those blocks (Santacana et al., 2010). These layers are presented in Fig. 1. The priorities of the governments in the implementation of the smart grid may be different. For instance, the U.S. focuses on energy-independence and security while the E.U. is more 13