For the promotion of competition, the establishment of new access infrastructures has been very important (”Several pipes to the home”), and in connection to this, broadband over power lines has been discussed, especially in Europe, for many years.
PLC utilizes the high frequency part of spectrum in the existing power line infrastructures. Electricity supply is provided in the low 50-60 Hz band and the frequencies over 1 MHz can be used for broadband. With regard to the capacity, PLC has been able to match DSL technologies in recent years. One of the important arguments for utilizing PLC as IP infrastructures has been the ubiquity of the physical infrastructure. Power line infrastructures have very high penetration and the idea has been that one can use this infrastructure to offer broadband in an easy way, and without establishing a totally new physical infrastructure. Another aspect is that all rooms in a household are connected to the power line infrastructure, and this allows for new and innovative services within the ‘intelligent home’ technologies paradigm.
PLC has suffered from several problems with noise and interference, which are solved today to a certain degree in the low voltage part of the power line infrastructure. At EU level, the EMC-directive is the only regulatory tool which can be used to assess the level of interference, and there is no agreement for harmonizing the interference requirements within power line (and other fixed infrastructures like xDSL). The EU recommends that the member countries remove any barrier to the development of services over PLC.
Even though the major technical obstacles like noise and interference are being solved, there are not that many market players (within and outside the power line business) that see any future for this technology as a means to deliver IP/broadband services. For more discussions about techno-economics of PLC, please refer to part III.
In Denmark, for example, only one power Line Company has commercial trials with PLC but they are planning to out-phase it and replace it with FTTH (Fiber To The Home) connections. Other power companies that have a very solid broadband business have decided not to put any efforts for PLC technology from the very first day and solely deploy FTTx technology in their networks. This is, however, the main tendency in power companies’ involvement in the IP business and what is evident is that the power companies get more and more involved in the IP/broadband business, but mainly by focusing on fiber technology.
PLC is deployed in a niche market with low scale in connection to some FTTx solutions. For example, when a big apartment complex is supplied by fiber to the cellar, connecting the apartments to this fiber requires that either the suppliers extend the fiber to all apartments, they establish a new electrical cabling to the apartments, or they use PLC to deliver broadband to the apartments. Here it has been shown that PLC is a good solution when the number of interested apartments is low. The strategy of the provider in this case is typically that the PLC is used only for Internet connectivity, and real triple/multi-play may wait until new broadband infrastructures are established.