"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.