Electrical energy is one of the main elements for the economical development of society. The just aspirations of modern societies to economical growth have forced us to secure more continual energy resources. On the other hand, climate change and international treaties aiming to reduce greenhouse gas emissions have prompted all of us to be increasingly concerned about energy efficiency and conservation. With the rapid growth of the information-based economy, widespread expansion of electronic devices has become a prevalent phenomenon in both the public and private sectors. Their suitability to perform various functions such as storage, management, processing and exchange of digital data and information, are essential support for information and communication technology (ICT). Although the consumption of energy may increase, influenced by the increase in the necessary communications infrastructure, the use of renewable energy may contribute to a more rational consumption of energy, reducing the impact on the environment. The current trend toward miniaturization in microelectronics, increased processing speed and greater functionality results in a particular sensitiveness to certain kinds of electromagnetic perturbations. Thus, this situation is not only bringing about a greater demand for electricity, but in addition higher levels of power quality and reliability (PQR) needs, in quantities and time frames that have not been experienced before.
