Commentary: Electric Internet-Web access via power lines could end

Barnaby Wickham

Whether a telecommuter has to get a big report to the big cheese in little time, or whether an avid collector finds the one item missing from her curio up for bid on eBay with time running out, many consumers feel they absolutely need fast Internet access.

For many people, however, the digital divide - being too far from existing telephone digital subscriber lines (DSL) and cable network infrastructure - makes buying broadband Internet access impossible or exorbitant.

Enter broadband over power lines (BPL), or the provision of high- speed Internet over existing power lines. The key word here is existing. In rural and out-of-the-way areas, the initial capital cost of installing the necessary infrastructure for DSL or cable networks more than outweighs the potential payback from future use. This is known as the last mile problem.

The lure of BPL is its potential to go anywhere existing power lines go, which is pretty much everywhere. Besides, BPL has the potential for much faster transmission rates. Using a computer simulation, Pennsylvania State University researchers determined that under optimal conditions, the maximum achievable transmission rate for BPL is close to a gigabit per second per kilometer.

Under same conditions and same length of line, copper cable [DSL] or coaxial lines [cable] don't come close, said Mohsen Kavehrad, a Penn State professor of electrical engineering and a co-author of the study. The reason for that is simple: With the copper and coaxial cable, the ground wire is right next to the conductor. This creates a lot of loss. With power lines, there is a 30-foot spacing between wires and the ground.

But creating the optimal conditions for BPL does prove to be a bit problematic. The trick is to keep the electric current from interfering with BPL's radio-frequency (RF) energy that travels on the same line. In theory, the two vibrate at different frequencies and wouldn't interfere with each other. But, especially at high voltages, electricity doesn't vibrate at a consistent frequency. That amount of power jumps all over the spectrum, creating a bouncing signal that can severely limit capacity.

What BPL providers must do is avoid high-voltage lines, instead transferring the data off of traditional fiber-optic lines onto medium-voltage power lines, which carry a more controllable 7,200 volts of electricity.

Because data can only travel so far on the medium-voltage lines before it degrades, the BPL providers then must install repeaters - special devices that amplify a fading data signal. Also necessary is new RF coupling equipment that bypasses data-blocking transformers that change line current from 7,200 volts to house-appropriate 240 volts.

Most BPL providers have chosen to forgo the additional conditioning required to achieve the very high transmission rates modeled by the Penn State researchers, figuring that customers won't place enough value on the increased capacity.

Still, the expense of the other power grid augmentations has some questioning the feasibility of BPL.

BPL advantages

Jay Birnbaum, vice president of Current Communications Group LLC, is not one of the naysayers. The privately held Germantown company where Birnbaum works is further along in testing and deploying BPL than any other company. With a pilot program in Rockville (in partnership with Washington-based utility PEPCO), and a large-scale rollout in the greater Cincinnati area, the company is aggressively promoting the merits of BPL through its affiliate Current Technologies LLC.

Since May 2004, Current Technologies and its power company partner, Ohio-based Cinergy Corp., have made BPL available to 50,000 homes in Cincinnati, with a penetration rate north of 10 percent, said Birnbaum. Significantly, more than half of the recruits defected from DSL or cable; about 40 percent migrated from dial-up.

So far, Current Technologies and Cinergy are recording 90 percent satisfaction rates, said Birnbaum. (It remains unclear how Cinergy's recent announcement of its sale to Duke Energy Corp. for $9 billion will affect future BPL implementation.)

Advantages of BPL subscription include identical upload and download speeds, the freedom to move from room to room (every electrical outlet is a port), and the ease of putting multiple computers online.

Monthly charges start at $29.95 for a maximum speed of 1 megabit per second, to $39.95 for a maximum speed of 3 megabits per second. For comparison, the $29.95 basic plan offers the speed of cable for a DSL price (DSL is generally slower and less expensive; cable is faster and pricier). Included in the price is a plug-and-play modem that connects to a PC via USB or Ethernet. A Wi-Fi-enabled wireless modem is extra.

Shows promise

There are, however, some remaining concerns surrounding BPL. Some claim that BPL interferes with short-wave radios used by ham radio operators and some emergency responders. Birnbaum says this hasn't been a problem for his company: We have had a sum total of zero [interference] complaints.

Also, there is some worry there still won't be an economic incentive to reach the most rural homes because of the additional equipment required to make power distribution lines BPL-ready.

For Current, the hardest part of implementing BPL has not been convincing customers, rather the most difficult thing is to get utilities to deploy the technology, said Birnbaum.

He expects this obstacle will cease as power companies begin to understand how BPL deployment ultimately will yield a smarter power grid. Eventually, power companies will be able to enjoy automated meter reading, remote switching, and power outage and restoration tracking in real time.

With Cinergy, before anyone called them, we notified them when there was an outage and where it occurred, said Birnbaum.

And that's not all. By October, Current plans to use BPL to offer Internet telephone services, known as Voice over Internet Protocol, or VoIP.

Clearly, the technology shows promise. With continued favorable rulings from the Federal Communication Commission and support from the White House (President Bush is a booster), BPL should increasingly become a viable alternative to DSL and cable.

Copyright 2005 Dolan Media Newswires
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