The main usage of power line communications has been by electricity companies for sending control signals at low rates and in several home automation products. It was only recently, spurred by the deregulation of the telecommunication and energy market in the late nineties, that communication over power lines has received a wider attention and is perceived by many as viable alternative or valuable complement to other wired or wireless communication systems. This is true for Internet access and indoor local area networks (LANs) particularly, where application of so-called broadband power line communications is considered. Broadband power line communications assumes service provision for multimedia applications consuming larger data rates and serving a limited number of users, and its new popularity is evidenced by two special issues on power line communications -based LANs and access networks, and the recent developments in the standardization for high-speed power line communications systems within the IEEE.
The single main advantage of power line communications over other wired communication solutions is the existence of a power line infrastructure. This, for instance, allows electricity companies to retrofit their power line networks for communication purposes at little additional costs. In fact, the energy distribution grid is perhaps the most ubiquitous infrastructure worldwide, and its extremely high penetration opens the door for a plethora of applications supported by power line communications. Alongside the aforementioned applications, especially the use of power line communications for advanced energy management has experienced a strong boost. Examples for this trend include the recently completed research and development project Real- time Energy Management via Powerlines and Internet (REMPLI), which involved nine partners from five European countries and was funded by the European Union, and the PoweRline Intelligent Metering.
Evolution (PRIME) project launched by the Spanish electric utility Iberdrola and joined by industrial partners from Europe and the U.S., whose goal is the specification of an open and non-proprietary power line communications -based telecommunications architecture that “could meet the future requirements on customer real time interfacing and smart grid evolution”. More generally, the ubiquity of power distribution lines renders power line communications an excellent candidate for industrial command-and-control and facility automation system, in which a common communication network connects a large number of devices that are spread over a wide area.