Broadband over powerline is ready to explode

You plug a cell phone-size adapter into any electrical outlet in your house and you've got 3M bit/sec. Internet service

Some call it "the third wire" and others call it "broadband over powerline" (BPL). But for Tim Barhorst, a technology consultant in Cincinnati, it's his Internet connection.

"It seems equivalent to standard cable service and a little faster than standard DSL," he noted. "But the speed is not asynchronous, meaning you get the same speed upstream and downstream."

Barhorst is getting his broadband Internet connection via BPL, through the power lines that run to his house, from a utility called Duke Energy, although the Internet service is handled by Current Communications in Germantown, Md.

Third-wire users like Barhorst are likely to become a lot more common in the next five years. Chris Rodin, an analyst at Parks Associates in Dallas, estimates that there are today no more than 150,000 BPL users in the U.S., but he expects to see the figure rise to 2.5 million by 2011, especially in rural areas unserved by cable or DSL.

Benefits of a smart grid

But the impetus to install BPL is not a desire by the power utilities to compete with AT&T or Time Warner, Rodin said. Rather, offering Internet service is an associated benefit of the power companies moving to "smart grids" that include components such as sensors and interactive controls. He pointed out that today a power company doesn't know that a transformer has failed until a customer calls to complain about the lights being out, but with a smart grid, faster responses and proactive maintenance would be possible. Thereafter, offering retail Internet service is icing on the cake, he indicated.

The benefits of a smart grid include smaller power outages and less loss of energy in transmission. Every day in the U.S. an average of 500,000 people experience a power failure of at least two hours, said Clark Gellings, vice president of the Electric Power Research Institute, a nonprofit research consortium in Palo Alto, Calif. The resulting annual loss of productivity has been pegged at $180 billion, he added.

But a smart grid ought to be able to cut those outages by 80%, he estimated. About 7% of power is lost in transmission, and smart grids should cut that loss by 10%, he added.

Meanwhile, power customers could have smart electric meters that automatically report usage, eliminating the need for meter readers. The smart meters would allow additional features, such as discounts for those who cut their usage during peak hours, sources agreed.

And, fortuitously, smart grids offer a perfect opportunity to offer more services to customers, such as BPL. "There is a lot of interest in BPL," noted Gellings. "It's the Holy Grail of the power industry to use the same wires that we use to deliver energy to communicate as well, but for years it was too cumbersome." And BPL only became realistic after several technical advances, he said, chiefly couplers that let the BPL signal bypass power transformers.

smart meter installation

TXU technician installs a smart meter as part of a broadband over powerline (BPL) installation. Utilities also have to wire the system capacitors in series instead of in parallel so as to not squelch the signal, and add signal boosters, he said.

"We are at an inflection point in the industry," agreed Ralph Vogel, spokesmen for Utility.net, a Los Angeles-based BPL integrator. "Its position is similar to that of DSL in the late 1990s: people have heard of it, and while we were previously not quite there yet with the technology, we are now."

Whereas passing a house with fiber can cost $1,500, no new wiring has to be installed to pass a house with BPL, he noted. A few modifications to the grid are necessary, plus a new meter, but the total is less than $150 per home, he said. The signal is injected into the grid within a neighborhood through a fiber or wireless backbone, and then shared by all the houses using the same transformer. Electrical interference inside each house caused by appliances is filtered by the plug adapters.

Currently the largest installation is the Duke Energy operation in Cincinnati. Duke Energy wouldn't comment for this article, but Jay Birnbaum, vice president at Current Communications, said that the Cincinnati system is not a smart grid yet. All houses on a transformer share the same bandwidth in an arrangement similar to that used by cable modems, using signal specifications set by the HomePlug Alliance. He declined to give the number of BPL subscribers on the Duke Energy network.

A utility called TXU, which serves the Dallas area with power, is likely to be the next big BPL installation, as it has committed $450 million to install 3 million smart meters, explained spokeswoman Carol Peters.

"We expect the vast majority of our system to be operating over BPL by 2011," she said. During trials on Jan. 31 the first grid fault was located using BPL, she said. It was a failed bolt on a neutral wire connector.

Internet service will be offered through third parties rather than directly from TXU, she said. Current Communications is partnering with TXU as it does with Duke Energy, and Birnbaum said that Internet service will be offered before summer. TXU's stated goal for investing in BPL is to improve customer service, a goal presumably related to the presence of competition in the consumer power market (akin to competition in the consumer phone market) in parts of Texas.

Centerpoint Energy in Houston has also reportedly begun investing in BPL, but didn't respond to requests for comment. The concentration of BPL activity in Texas is apparently connected to the passage of the Texas Public Utility Regulatory Act of 2005, which freed BPL from municipal regulation and additional right-of-way taxes in Texas, explained Terry Hadley, spokesman for the Texas Public Utility Commission in Austin.

Regulatory concerns

And indeed, the regulatory environment will have lot to do with whether an individual power utility (of which there are about 3,200 in the U.S.) decides to install BPL, noted Gellings. "The regulators allow investor-owned utilities [only] a certain return on their investment, and that will apply to the investment involved in putting BPL on the grid," he said. Rural electric co-ops don't have that cap on their ROI, he added.

Actually, regulation has been an issue since the first experimental BPL modems were turned on, due to complaints of interference by ham radio operators. Allen Pitts, spokesman for the ham radio parent organization, the American Radio Relay League (ARRL) in Newington, Conn., said that the utilities installing the latest technology (including the ones in Cincinnati and Texas) are not a problem since the frequencies they use are "notched" to avoid ham frequencies. But there are a number of older BPL experiments that continue generating interference, he complained, causing problems not only with ham operators but with emergency services that use older equipment in the FM ranges. In fact, he said that the ARRL has filed suit against the Federal Communications Commission to force the government to act against them.

Indeed, the ARRL follows the BPL situation closely, and counts 34 trial BPL systems that have been shut down, often because of interference complaints or because they were judged uneconomical. Another 54 systems are currently operational and 19 more are pending.

Back in Cincinnati, Barhorst said he gets Internet service at a speed of about 3M bit/sec. through any power outlet in his house, using an adapter about the size of a cell phone. He has never noticed any degradation caused by electrical noise from home appliances, or any interference with Wi-Fi. There is some loss of throughput on the outlets farthest from the service point, he noted, but that is not an issue because he uses an existing Ethernet network that he plugs in to an outlet near the service point. With its symmetrical speed, he can use the service for a Web server for his amateur photography site.

"I can't get same bandwidth for any price close to it from another carrier," he said.

For more information:

Power line communication Wikipedia entry

BPL Today

Howstuffworks "How Broadband Over Powerlines Works"

Lamont Wood is a freelance writer in San Antonio.

Copyright © 2007 IDG Communications, Inc.

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