BPL Talking Points

BPL “Talking Points”

By

Rich Moseson, W2VU, for the

ARRL Public Relations Committee

• What is BPL?

  • BPL is short for Broadband over Power Lines. It’s called Power Line Communications, or PLC, in some places.

  • Essentially, BPL is high-speed Internet service delivered via electric power lines.
    
     

• What are the benefits of BPL?

  • In densely-populated areas, it would provide consumers with a third option for high-speed Internet access, in addition to cable Internet service and the phone company’s high-speed DSL (digital subscriber line) service.

  • In sparsely-populated areas, it could theoretically make high-speed Internet access available in locations that do not currently have cable or DSL broadband access. Theoretically.
    
     

• Why theoretically?

  • Electric wires are designed to carry electricity, not data. They cannot efficiently carry data very far, and a utility installing BPL would have to invest in a network of fiber-optic cables and amplifiers to bring the Internet signals to a distribution point for the “last mile” to subscribers’ homes. In addition, they’d have to manually bypass every transformer along the lines, since data signals cannot pass through transformers. This is all very expensive and it’s questionable whether cost-conscious utilities will make the investment in sparsely-populated areas where there is only the potential for one or two subscribers in given area.
    
     

• Is BPL in use anywhere yet?

  • There have been several test areas, generally covering a neighborhood or other small area. Large-scale deployment of BPL is only just beginning as of early 2004.
    
     

• What’s the problem that ham radio operators have with BPL?

  • In a word, interference – in both directions; BPL interfering with ham radio communications and strong signals from nearby ham transmitters shutting down people’s BPL Internet service. And it’s not just hams. All users of the shortwave and low-VHF parts of the radio spectrum could be affected.

  • Power lines, unlike cable TV lines, are not shielded. This means that any signal sent down those lines at radio frequencies will “leak” from the power lines. That means they also receive radio signals. Any nearby signals would be sent straight to a customer’s computer.

  • The biggest problem is that these BPL systems use frequencies between 2 MHz and 80 MHz. This includes the shortwave bands, between 3 and 30 MHz, which are the only frequencies in the whole radio spectrum on which worldwide communications are possible without using satellites or other relays.

  • Users of these frequencies include not only ham operators but aircraft pilots, the military, ship-to-shore, international broadcasters and others. At the high end of the range, you have many emergency service agencies and the lower TV channels (2-4). While many of these services operate away from residential areas where BPL may be installed, even low-power radio signals in this frequency range may often travel hundreds or even thousands of miles.

    • Some of the radio uses/users affected by BPL on 2-80 MHz:

      • TV channels 2, 3, 4 (56-80 MHz)

      • Kids’ walkie-talkies (27 & 49 MHz)

      • Older cordless phones (49 MHz)

      • Some wireless baby monitors (49 MHz)

      • Radio-controlled cars, boats, planes (27, 49, 72 MHz)

      • CB (Citizens Band) radio (27 MHz)

      • International shortwave broadcasters (various frequencies, 2-25 MHz)

      • Amateur (ham) radio (various frequencies, 3-54 MHz)

      • Military (various frequencies, 2-80 MHz)

      • Police/Fire/EMS (30-50 MHz)

      • Federal law enforcement (various frequencies, 2-80 MHz)

      • Federal Emergency Management Agency / Dept. of Homeland Security (various frequencies, 2-80 MHz)

      • Airlines / Air Traffic Control (2-22 MHz)

• Have any companies testing or installing BPL systems tried to work with radio users?

  • Yes, some have worked closely with radio users; others have been completely uncooperative.

  • Some companies have offered to “notch out” or skip over frequencies used by certain radio services. But it hasn’t been very effective in tests so far and skipping over all of the frequencies currently in use by other radio users would leave the BPL folks with “all hole and no doughnut,” so some users are certain to suffer regardless.
    
     

• Are there alternative approaches that won’t result in these interference problems?

  • Yes, several companies are working on different ways to achieve the same goal:

    • The municipal utility in Owensboro, Kentucky, is using wireless networking technology rather than power lines for the “last mile” to customers’ homes. With this system, laptop computers, personal schedulers, etc., wouldn’t even have to be plugged in to have Internet access. With standard BPL, a device would need to be plugged into a wall socket.

    • Another company recently announced a BPL system that uses frequencies near the area where wireless networks operate. In these frequency ranges, there is much more “open space” with far fewer users. In addition, radio waves at these frequencies don’t normally carry very far, so there’d be no possibility of signals causing interference thousands of miles away, as they might with standard BPL in the 2-80 MHz range.
      
       

• What makes the 2-80 MHz frequency range so special?

  • This covers the entire shortwave and low VHF portions of the radio spectrum. These are the only frequencies capable of supporting worldwide radio communications without relay devices such as satellites. This is a unique part of the radio spectrum that must be protected. Interference from BPL would cover all of these frequencies all of the time, often with very strong signals and sometimes in locations hundreds or thousands of miles from the source of the signals.
    
     

• If BPL comes into use here and there are interference problems, who would be responsible for ending the interference?

  • Technically speaking, the utility would bear full responsibility for resolving the interference problem by taking any necessary steps, up to and including shutting down the service in a given area.

    • BPL is not a licensed service, meaning that neither the sponsoring utility nor the individual user would need a license from the Federal Communications Commission, or FCC. Other users of the same frequencies, such as broadcasters, police and fire departments, and ham operators, must have FCC licenses.

    • The law is very clear that if an unlicensed service causes interference to a licensed service, then the unlicensed service must resolve it or shut down. Likewise, an unlicensed service must tolerate any interference it receives from a licensed service.
      
       

• Then what’s the problem?

  • Well, the law is one thing; reality is often something else. Most people don’t understand or want to understand the technology involved. They just want it to work. If your Internet service works fine except when I’m transmitting, then the logical conclusion is that the interference must be my fault and that I’d better fix it or stop transmitting. You can explain the law until you’re blue in the face and it still won’t overcome what seems to be very clear logic.

  • The biggest problem, though, is likely to be interference from BPL to licensed radio services. Are you going to shut down dozens or hundreds of people’s Internet access because of interference to a relatively few radio stations? Legally, yes, but it won’t win you any friends in the Court of Public Opinion. And we hams don’t want to have fights with our neighbors. We want them to enjoy their broadband Internet service, but we also want to continue to be able to operate our radio stations, and to be ready to help our neighbors in an emergency, as we’ve been doing for decades.

  • From the consumer’s point of view, if you pay a premium for high-speed Internet service, you expect it to be there when you want it – and not to possibly need to be shut down because the fire department or the taxi company can’t communicate when they’re in your neighborhood.
    
     

• The FCC says it’s confident that the rules it’s proposing for BPL will permit any interference to be quickly tracked down and resolved on a case-by-case basis. Do you think the FCC is wrong?

  • There are three problems here:

    • First, the FCC anticipates that any problems will be resolved by notching out, or removing the signal from, frequencies or bands of frequencies on which interference occurs. With the ability of even low-powered signals to travel great distances on shortwave frequencies, it is entirely possible that there will be interference to someone somewhere on nearly every frequency. You can’t notch out everything or you’ll have not spectrum left for the BPL signal.

    • Second, the interference problems need to be addressed more seriously before there is any widespread deployment of BPL. Once the genie is out of the bottle, it’s going to be impossible to get it back in. If there is widespread acceptance, as the FCC hopes, and widespread interference, as we fear, it’s highly unlikely that the FCC is going to start shutting down systems and taking away people’s broadband Internet access, especially considering how much the FCC has been promoting BPL as, in the words of one Commissioner, “broadband Nirvana.” The radio users will just have to suffer the consequences regardless of the letter of the law, and a unique natural resource – the shortwave radio spectrum – will be lost forever.

    • Third, the FCC is relying on the utilities to track down and resolve any interference problems. But power line interference to radio users, even without BPL, is a significant problem, and the FCC’s Enforcement Bureau can tell you that power companies are often very uncooperative in helping to resolve existing problems … let alone the hundreds or thousands of new complaints we expect if BPL is put into widespread use.
      
       

• So, in a nutshell?

  • Imagine that the police and fire departments couldn’t communicate while in your neighborhood because of interference from BPL. Or that your cordless phone, or kids’ walkie-talkies, or radio-controlled models won’t work anymore. Imagine that long-range interference from BPL signals (even weak signals) made it difficult or impossible for airline pilots, the military or federal emergency management officials to communicate; that ham radio operators couldn’t practice and sharpen the skills they’ll need in an emergency … all for one more way of getting fast Internet access in high-population area or an economically-dubious way for rural areas.

  • Especially in light of last summer’s massive power blackout in the Northeast, and the realization that our nation’s power grid is held together with Band-Aids and Scotch Tape, we think the power companied should leave the Internet business to communications companies and focus their resources on strengthening and modernizing the electric distribution system … or as the president of our national ham radio organization says, “the power companies need to forget BPL and concentrate on PPL – Power over Power Lines!”

_______________

© Copyright 2004, CQ Communications, Inc. All rights reserved. This material may not be reproduced or republished, including posting to a website, in part or in whole, by any means, without the express written permission of the publisher, CQ Communications, Inc. Hyperlinks to this page are permitted.