Hydro-Qubec is planning to offer high-speed internet service over its power lines to compete with similar services from cable and telephone companies.

The utility already uses signals over its power lines to control stoplights, but now it wants to adapt it to offer internet access.

Some experts say such a service could be up to five times faster than high-speed cable internet service.

Jim Carroll, author of "Surviving the Information Age," said the addition of the new service could be great for consumers.

"If we have that many participants in the broadband marketplace then the real impact is perhaps it's going to help to keep prices down or drive down the monthly price," said Carroll.

Jean-Paul Galarneau, of the Quebec cable company Vidotron, said its service will stand up to the competition.

"Videotron has to compete with satellite, we're doing pretty well today, and we're ready to fight with any competitor," said Galarneau.

But some broadcasters use electrical wires as antennas for radio signals and are concerned that the internet signals could interfere with radio and television reception.

Broadcast expert Jacques Bouliane said the internet signal could completely ruin television reception.

"Even if you don't subscribe to the service, you would get interference from it," he said.

Hydro said it won't be a problem, and pointed out that interference doesn't occur over cables that provide both television and internet service.

German utilities company RWE started offering Internet service over power lines the summer of 2001, but went out of the business in 2002. Scottish Hydro-Electric offers broadband Internet service over its power lines.

Canadian tech company Nortel ran tests of the technology in Britain in the late 1990s and concluded that it would be far too expensive to adapt power grids to carry internet signals.

Hydro-Qubec said it will start testing the service in January and hopes to offer the service in a few years.