SAN DIEGO —— Representatives of companies that generate electric power said Tuesday that they want to see a new high voltage transmission line strung diagonally across the county, while consumer advocates and energy consultants countered that they would prefer not to see it built.

Speaking at a San Diego Association of Governments workshop in San Diego on Tuesday, Dave Geier, vice president of electric transmission and distribution for San Diego Gas & Electric Co. who represented the utility on the panel, said his company expects to file an application for a new 500 kV transmission line "as soon as possible." A 500 kV line is energized with 500,000 volts, about 4,500 times the power level of a common household wall outlet.

Electricity generators argue that the high voltage line is needed to justify expanding geothermal and solar energy generation projects in Imperial County. Geier cited his company's goal of obtaining 20 percent of its electricity from such renewable sources within five years. Bringing that power efficiently to its customers requires the 500 kV pathway, he said.

Moreover, he said, the pathway is needed should San Diego have to import power from northern sources —— a prospect that Duke Energy's South Bay project manager, Andrew Trump, said seems likely as older production units in the region are retired. Available electricity could fall short of peak demand, even with newly developed regional power generation, as early as 2009, he said.

The new line, if built, would begin north of El Centro, pass through East County and north of Escondido, then follow Interstate 15 into Riverside County, connecting to an existing high-voltage transmission network in western Riverside County near Lake Elsinore. The portion of the route from Escondido to Lake Elsinore is not the same as that of the Valley-Rainbow transmission line that was hotly debated in 2002, but never built.

The proposal to build a new high-voltage line across the county is included in the California Independent System Operator's Southwest Transmission Expansion Plan, with a target in-service date of 2011. The plan was reviewed at the meeting by Jeff Miller, CAISO's regional transmission manger.

But Bill Powers, president of Powers Engineering and chairman of the Border Power Plant Working Group —— a bi-national energy interest organization —- said that although the completion of the cross-county 500 kV line "may provide some benefits locally," constructing it would take away the leverage local commercial electricity customers now have over generator units near the U.S.-Mexico border.

"All the important benefits of the 500 kV transmission loop will go to the generators, allowing them to sell their electricity to distant markets," he said.

Lower voltage transmission lines are less efficient for long-distance transmission, so the existing network of transmission pathways favors consumers who are within local transmission distances using the 230 kV lines now available to the generators.

According to Michael Shames, executive director of San Diego's Utilities Consumers Action Network and who gave an overview of competing regional energy plans San Diego Regional Energy Infrastructure Study at the workshop, Powers is on the right track.

Contact staff writer Edmond Jacoby at (760) 739-6675 or ejacoby@nctimes.com.