Electrical Power Companies have been using overhead power transmission lines for transmitting data for many years now. However, it was in October 2004 that the Federal Communications Commission (FCC) approved rules for Broadband over Power Line (BPL) technology.

Electrical power companies provide BPL by making use of power grid for transmitting data -by superimposing a (high frequency) carrier signal -over the traditional Alternating Current frequencies (60Hz or 50Hz depending on what the power companies are using in your part of the world) that are used for bringing electricity to your location.

Is Broadband over Power Line (BPL) a New Development?: Not really. Broadband Over Power Line (BOPL) or simply Broadband Power Line BPL is not a new phenomenon or a new breakthrough in technology -it has been one of the most reliable, and cost effective methods of communication used by power station control room personnel for transmitting voice and data between power generating stations, and various substations that are often located in remote/unpopulated areas.

During the pre-cellular telephone era, not many alternative modes of communication were available to electrical company personnel working at remote power plants and substations. Since there were no other alternatives, electrical engineers had figured out a way to superimpose a high frequency signal (a.k.a. Carrier Signal) over low frequency electrical power line, and modulate it to transmit telemetry data and voice.

What is so Unique/New About Consumer Grade BOPL Products Now being Offered by Power Companies? Nothing from a technical point of view. What is new is that it is now being explored as a commercially viable consumer product. Power companies are (rightfully) trying to scale up what has historically been used for transmitting miniscule amount of data -in hopes of making a commercially viable consumer product out of it.

In doing so, power companies are (quite understandably) trying steal a bone from Telephone companies and TV/Cable Network companies who are also trying to take a bite out of each other's marketshare by cross selling their products.

Even though the Electrical Power Companies that offer BOPL have unique advantages, they also face quite a few equally unique challenges as outlined below:

What is Good About BOPL Service Offerings?

• Existing Right of Way: Electrical companies already have access to every building -residential and commercial. They do not have to pay for acquiring "right of way" (Last Mile Access-Rights) to their consumers' CPE (Customer/Consumer Premise Equipment) demark interfaces.
  
• Name Recognition: Everybody knows their Power Company. Being seen as an established/well-known local business entity has advantages.
  
• More Options for Consumers: Availability of BPOL products might be a good news for those that may be located in a remote area where not many Telco and TV/Cable companies may be competing. New competition from power companies may give them more choices, lower their cost, and possibly provide them access to better services.

What Problems Power Companies Face with their BOPL Service Offerings?

• BPL and Scalability Issues: Just because a pair of cans and a string works for tiny and occasional transmissions, it does not mean it can be scaled-up to support transmission of large volumes of data -especially for multi-stream video and audio applications that have greater QoS demands.
  
• BPL is Inherently Insecure: Just like TV/cable companies, power companies have no way of isolating/partitioning data packets on per consumer basis. Everyone's data packets are potentially readable by everyone else that buys service from your power company.
  
• BPL Involves Potentially Unsafe Use of Power Grid Components Beyond Their Design Specifications: Everything from Ceramic Insulators, Cable Sheaths, Power Transformers, Circuit Breakers, to Residential Circuits/Wiring is designed for low frequency (50Hz or 60Hz) AC signals. Dielectric losses that occur when such devices are used to continually carry higher frequencies are not the same as what they would have been while operating under the environment/duty-cycle that they may have been designed for.
  
• BPL Causes Radio Frequency Interference to Other RF Users: All current carrying conductors produce/radiate electromagnetic force (EMF) signals. When electricity conductors (power lines) in your city are used to carry high-frequency signals, it can potentially transform the entire network of power-lines into a massive citywide mesh/array of antennas. Several HAM radio operators and various other radio frequency equipment users have already reported excessive RF noise issues to FCC.
  
• Potential Health Risks Due to Excessive Exposure to Radio Frequency Signals: While it is unlikely that everyone living in your city is going to get cooked or is going to start having a glow; concerned people have asked for careful examination of potentially harmful effects of long term exposure to high frequency RF signals emitted by powerlines/conductors used for provisioning BPL.
  
• Additional Customer Support Staffing Needed For BPL Users: Power companies have well-trained and dedicated employees that know how to maintain electrical grids, how to dispatch trucks to quickly restore broken powerlines, and how to restore power as quickly as possible. However, those tasks are a bit different than doing tech support for broadband lines. Providing quality customer support to masses --especially while trying to make profit from a consumer grade product that has thin profit margins --is not an easy task. Even many of the telephone companies and TV/cable networks that have had about 15 years of headstart are still performing dismally when it comes to customer service. Most electrical power companies that wish to sell BPL to consumers will need to allocate funds for hiring and training many customer care professionals to support their BPL clients.
  
• BPL Subjects Consumer Electronics to Noisy/Dirty Electrical Power: When one connects dirty power lines (ones that carry excessive high-frequency noise superimposed over traditional low-frequency transport) to consumer electronics products; it is bound to have detrimental effects on every power converter, step-down transformer, and ac-to-dc rectifier built into them. Most power converters (rectifiers) have filters (capacitors and inductors) that are often equipped with a RC tank circuit that is tuned for filtering out low frequency (50/60Hz) noise. High frequency noise injected into your electrical system, therefore, can cause unspecified damage to your power supplies, electrical clocks, AC motors and most of your electrical/electronic gadgets.

Unless you are stuck in a remote location that does not have access to broadband wireless, Telco-provisioned broadband landlines, or broadband satellite services; you may not want to rush into injecting high-frequency buzz (carrier signal noise) onto your otherwise clean (50 or 60Hz Sine-wave) Alternating Current power lines. As this technology continues to evolve, however, and new technological innovations (such as High Frequency Power Line Filters that one can install on power-outlets to block/filter-out carrier signals from reaching sundry electrical gadgets) emerge and mature; BPL can certainly become a viable option for providing high speed Broadband Internet Access in certain markets.

Most power companies are still exploring the many unknowns (including competitive, legislative, operational, and technical issues) related to this rather relatively new consumer grade data-product. Therefore, it may be quite some time before you would have an option to use BPL for bringing Broadband Internet Access to your location.