Plugged In: Broadband over power lines goes live

Virginia telecom delivers on broadband-over-power-line initiative for utility.

When Sean Porter wants to transmit drawings and other large files via e-mail from his office at Robert B. Loveless Architects, he just has to plug his computer into a wall outlet.

That's because Porter and his six colleagues have been using a broadband-over-power-line (BPL) Internet service for the past two years. Communication Technologies Inc. (ComTek), a Chantilly, Va.-based telecommunications and IT integration company, owns and operates the BPL service for the Department of Public Works of the city of Manassas. The service is fast and reliable, Porter says, and the only piece of equipment he needs is a modem the size of a portable CD player that sits on a closet shelf and connects to the office switch.

The technology that makes Internet connectivity possible over standard power lines is pretty simple. Manassas uses $350 fiber-optic modems that are encased in boxes approved by the National Electrical Manufacturers Association (NEMA). The boxes are about the size of a VHS tape and are installed near transformers. Also contained in the NEMA box is a concentrator unit that connects Ethernet to BPL. The customer at the other end simply needs a modem and an Ethernet jack.

"It's deceptively simple," says Walter Adams, a vice president at ComTek.

"It's very similar to the DSL service I use at home," says Porter. He adds that he was surprised by the flexibility of the system. "You can just go into any room and plug it in."

That kind of flexibility—plus the speed, cost and reliability of the BPL service—has helped Manassas sign up more than 200 residential customers, or 10% of the homes in which the service is available. There are 1,300 customers on a waiting list, Adams says.

The city expects to spend about $500,000 enhancing its telecommunications and electrical infrastructures by the time ComTek completes the network installation at the end of March, says Mark LeRoy, utility finance manager for Manassas. He anticipates a six-year return on investment.

Under its revenue-sharing agreement with ComTek, Manassas is paying for fiber-optic equipment that's being installed throughout the 10-square-mile city and is subcontracting its field workers to ComTek to install the modems, concentrator units, fiber Ethernet connectors, repeaters and other BPL equipment.

Manassas Public Works had about 30 miles of fiber-optic wiring installed throughout the city before the BPL deployment began, and it expects to add another 125 miles by the end of this month, says Brett Massey, manager of energy services for the city.

At a cost of $28.95 per month for residential service and $39.95 per month for commercial service at a minimum speed of 300Kbit/sec. to and from the Internet, Manassas' BPL service compares favorably to the $42.95 that Comcast Corp. charges cable-modem customers who also subscribe to its cable television services. Cable throughput is typically 600Kbit to 800Kbit/sec. from the Internet to the subscriber and 128Kbit to 256Kbit/sec. to the Internet.

To date, just a handful of U.S. electric utilities have deployed BPL Internet services, says Jim Spiers, an analyst at Meta Group Inc. in Stamford, Conn. They include Cinergy Corp. in Cincinnati and Idacorp Inc. in Boise, Idaho.

Technical Hurdles

There are technical shortcomings that can hamper BPL service. "Electric lines are not designed to carry data," says Adams, who notes that splicing of power lines can weaken the Internet bandwidth signal they carry.

In addition, some above-ground BPL equipment can rust within a matter of months as a result of corrosion caused by saltwater in coastal areas. Meanwhile, some of the cladding that surrounds underground fiber-optic connections is soy-based and can entice groundhogs to chew through the wires, a challenge facing all fiber-optic network operators. Eighty percent of Manassas' BPL network is below-ground, but it has yet to encounter any rodent problems, says Adams.

Still, he acknowledges that BPL gear "doesn't snorkel well" when underground equipment is exposed to flooding. "We've tried to protect them with $100 boxes, but we've discovered that Ziploc bags and tape actually work best," says Adams.

Corrosion problems can be solved, says Zarko Sumic, an energy industry analyst at Meta Group. The biggest technical challenge for BPL is the inductive nature of transformers, says Sumic. Electromagnetic induction can produce voltage across a conductor situated in a changing magnetic field. Because transformers are inductive, BPL providers have to install bypasses around the transformers in order to maintain a steady signal, says Sumic. "You don't have that issue with cable," he adds. The BPL equipment that ComTek uses will work through the transformer without having to bypass it, says Adams.

"Not all [BPL] equipment is created equal," says ComTek President and CEO Joe Fergus. For instance, ComTek installs BPL equipment from Main.net Communications Ltd., an Israel-based BPL equipment manufacturer whose gear is "among the most stable in the industry," he says.

Main.net is planning to introduce next-generation BPL equipment this quarter that can support 4Mbit to 6Mbit/sec. capacity to customers, says Adams. ComTek is preparing to offer Manassas customers tiered services, so customers would pay different rates for, say, 1.5Mbit/sec. and 2Mbit/sec. service, says Adams.

Manassas officials remain bullish about the potential of BPL. "It's not a 'get rich quick' scheme, but it's really starting to take off," says LeRoy.

1pixclear.gif
BPL: How It Works
Please click on image above to view a readable version.

Copyright © 2005 IDG Communications, Inc.

7 inconvenient truths about the hybrid work trend
Shop Tech Products at Amazon