supplies that usually reach customer meters through overhead lines.
LV overhead lines may use either bare conductors (usually aluminum or copper) supported on glass/ceramic insulators or an aerial bundled cable system to be laid outdoor on poles or wall‐mounted.
LV underground lines are often found in medium‐ to large‐sized towns and cities, inside utility tunnels, laid in ducts or tubes, or directly buried in trenches. These cables show a typical structure of conductor insulated with similar materials to those discussed for MV (the metallic screen is not mandatory) and are protected by an outer PVC jacket.
1.3 A Practical Definition of the Smart Grid
Electric power systems have evolved and adapted to the growing needs of electrification both in terms of reach and of power consumption increase. From the first isolated and single‐purpose grids to the nowadays interconnected power systems, the grid has enlarged its capability and has achieved the high marks that allow the rest of the society assume the supply of energy as a commodity.
However, the adoption of changes in power systems is not as dynamic as in other domains, industries, or services. Indeed, a fast transformational pace is not a key characteristic of utilities both because technology cycles in utility industry take longer than in other industries, due to the substantial investments required by many of their infrastructures, the regulation and the endurance expected in electricity service.
All in all, the evolution of the grid over the last decades, probably since the 1980s, has been accelerated, but more strongly since the term Smart Grid was coined. However, there is no standardized or globally accepted definition of it; instead, Smart Grids are defined differently around the world, in different world regions, in different utilities, by different regulators, etc., to reflect local requirements and goals [17]. Moreover, from the initial references to the Smart Grid concept in the 1990s (when Smart Grid was not the commonly agreed expression yet – see [18–20]), the successive examples, implementations, and instances of Smart Grids have shown such a divergence as the one included in the wide scope of the ideas behind the concept.
Grid modernization [21] has been an overarching concept in the Smart Grid evolution. Although the idea collates a great variety of grid evolutionary material aspects, grid assets refresh, adoption of new grid‐edge technologies [22], new technologies in energy storage and microgrids domains, and large shares of renewable energy (i.e., DER) have emerged as principal components. All these elements aim at a change toward a more resilient, responsive, and interactive grid [21], to improve the reliability of the system (network and services).
For this purpose, these technologies must be properly integrated in the systemic, operational, and regulatory framework of utility business. Therefore, referring to utility business, legislative and regulatory actions have been taking place to allow these business changes to be introduced. Indeed, utility business, regulatory framework, and associated utility rates are in constant revision to adapt to the new reality. In this new context of energy as an enabler of our Society progress, and with the environmental concern as a major one, the role of consumers comes also into perspective. Consumers overcome their role as passive objects of the electric system and appear as active pieces of the overall service experience taking an active role in system‐wide performance (helping to shape the system requirements and operations through their active participation producing and storing energy or adapting consumption patterns). The active participation of the different stakeholders (customer being a central element) in the system will achieve higher levels of energy efficiency across the value chain.
Future power grids may not be equal to those of today. However, taking into consideration the history behind power systems, we can state that power grids will not be radically different in neither the short nor the medium term, and the changes will happen in an evolutionary way. Thus, existing grid infrastructure will play a key role, and its integration with the new grid technology is both a must and a key in the process of leveraging existing assets.
And it is here that ICTs, also commonly referred to as digital technologies [23], come into play. The advances in electronics, computation, and telecommunications gathered around the ICTs are continuously impacting different aspects of our Society.
Utility industry is a very special (neither minor, nor simple) example of adoption of ICTs. Although some in utility industry write the equation “Smart Grid = Grid + ICT,” this is an excessive simplification. While it is true that ICTs integration is one of the most prevalent ideas behind the quest for “Smart” in the Grid, there are many other components that are instrumental. What it is also true is that the incorporation of ICTs to human activities does not by itself improve them, and this is why the role of ICTs for the grid in its evolution toward a smarter grid must be understood in terms of “enablement” of what needs to happen in the grid, with the new ICT capabilities helping both existing and new grid components to seamlessly integrate with the grid as an enhanced system.
Some high‐level definitions (Table 1.2) have had a higher impact driving actions enabling the Smart Grid. Within the idealistic vision drawn by them, sits the ambition of a “better” electric grid, superior to the existing one, characterized or involving the following elements:
Resilient electric power system.
Grid infrastructure modernization.
Power quality assurance.
Efficiency in the power delivery system and in the customers' consumption.
Reduced environmental impact of electricity production and delivery.
Combination of bulk power generation with DG resources.
Storage as technology increasingly available in the grid edge.
Automation of operational processes.
Increased number of sensors and controls in the electricity system.
Monitoring and control of critical and non‐critical components of the power system.
No two conventional grids are the same today. Thus, even with common objectives, and despite the efforts in standardization and proper frameworks definition, Smart Grid implementations in utilities will be different one from the other.
1.4 Why Telecommunications Are Instrumental for the Smart Grid
Out of the four high‐level definitions of Smart Grids in Table 1.2, two of them refer to ICTs when they mention “digital technologies.” It is encouraging that high‐level definitions come that close to our topic of interest.
Technical references on Smart Grids show a more precise idea of the relevance of ICTs and Communications in particular. Franz et al. [29] highlight the “convergence of the electricity system with ICT technologies” aspect of the Smart Grid; [30] is more comprehensive with the purpose and signals the difference between information technologies and communications (“two way exchange of electricity information”) in its application to the Smart Grid: “A Smart Grid refers to a next‐generation network that integrates information technology (Smart) into the existing power grid (Grid) to optimize energy efficiency through a two‐way exchange of electricity information between suppliers and consumers in real time.” This approach is also expressed in [20] that highlights the enabling aspects of the different components of the ICTs, in connection with the elements of the grid, and the ultimate goal of getting smarter grids (“A Smart Grid is the use of sensors, communications, computational ability and control in some form to enhance the overall functionality of the electric power delivery system”), and in [18], that is more explicit in what the improvement of the grid should be (“The IntelliGrid vision links electricity with communications and computer control to create a highly automated, responsive and resilient power delivery system”).
The importance of the communication’s