A bitter three-year battle over a mammoth power line reached a crucial milestone last year, with both sides claiming partial victory as the state gave San Diego Gas & Electric Co. permission to build its $1.9 billion project - though not where it wanted.

In rejecting a North County route for the Sunrise Powerlink, the California Public Utilities Commission voted 4-1 on Dec. 18 to approve the 1,000-megawatt, high-voltage line along an alternate path through the southern part of the county. And commissioners gave SDG&E the green light to spend up to $2.1 billion on the line.

The cost is to be spread throughout the state, with local ratepayers footing about 10 percent. Sunrise is expected to deliver about one-fifth of San Diego County's electricity.

The long-awaited decision followed dozens of public hearings and rallies, and the release of an 11,000-page environmental study -- the largest ever for a utility project in California. The project was one of the most contested in San Diego County history.

Construction could begin in 2009, and the wires could be energized by 2012.

But first, more developments lie ahead for Sunrise Powerlink.

Both sides are waiting for a decision from the U.S. Bureau of Land Management in early 2009 determining whether SDG&E can string wires across federal land. And a coalition of consumer advocacy and environmental groups has vowed to challenge the state decision in court.

While the final word has yet to be spoken, the Sunrise debate has come far since SDG&E proposed in late 2005 to build metal towers 160 feet tall to boost the region's electricity supply and plug into Imperial Valley green energy.

The Anza-Borrego obstacle

SDG&E contended the best place to lay its giant extension cord was along a 150-mile route between El Centro and Carmel Valley, running through Anza-Borrego Desert State Park, Santa Ysabel, Ramona and Rancho Penasquitos.

But the plan ran into a firestorm of opposition from environmentalists, frequent park visitors and backcountry residents. They maintained the line would lower property values in residential neighborhoods, increase the region's already high wildfire danger and ruin one of the nation's largest state parks.

The prospect of an industrial-style project in a wilderness with seemingly endless vistas forced the utility to back away from its preferred North County route. But ultimately the project, with a different route, was allowed because it promised to tap desert sun and wind power, and it had the support of Gov. Arnold Schwarzenegger.

SDG&E officials set aside their frustration about not getting the route they wanted and cheered the approval.

Opponents cheered the defeat of the hated northern route. But they made it clear they weren't pleased that the state had still authorized a power line -- something they contend is not needed.

At the least, said Steven Siegel, attorney for the environmental group Center for Biological Diversity, the commission should have made SDG&E commit to putting specified amounts of sun and wind power on Sunrise's wires.

"The state is sacrificing public lands and vital habitat without any guarantee the line will be used to deliver clean energy," Siegel said.

Commissioners dismissed that concern, saying they have authority to ensure that green power, and not fossil-fuel power, is shipped because of their oversight of SDG&E contracts with electricity providers.

The commission's decision is expected to be followed in January by a Bureau of Land Management ruling about whether SDG&E can cross federal land. Approval is expected. Federal officials expressed a preference for the approved southern route in the environmental report they helped write.

Shifting to the courts

As for opponents' threat to challenge the state decision, they have until Jan. 18 to request a rehearing. Michael Shames, executive director for the San Diego advocacy group Utility Consumers' Action Network, said that if the request is denied, opponents will take their case to a state appeals court.

Some opponents are looking forward to having their day in court.

Bill Powers, an air quality engineer and activist who lives in San Diego, said, "We're finally getting to the real game, which is a chance to present the arguments in a forum with much less political influence - in a court of law."

SDG&E officials say they are confident the commission's ruling will survive any challenge.

Despite assertions to the contrary, company officials maintain that the power line will be needed early next decade to keep the lights on and air conditioners humming.

And company spokeswoman Jennifer Briscoe said the economic downturn has not changed that.

"We have not seen any significant decline in electric demand in recent months," Briscoe said by e-mail on Dec. 18, the day the state decision was handed down. "There has been a drop in the number of new customers added, but usage per customer has actually risen and is higher than where we expected it to be at this time."

SDG&E also maintained -- and the state utility commissioners agreed -- that the line is needed to help the region meet a 2020 state mandate to obtain one-third of its electricity from green energy sources. Company officials say the most promising of those sources are in the desert.

But Powers maintains that all 1,000 megawatts on the line could be delivered from solar panels on rooftops of local warehouses, big-box retail stores, government offices and parking garages.

Noting that in July, SDG&E proposed a rooftop and parking-lot solar project to deliver 70 to 80 megawatts, utility spokesman Scott Crider said the region needs local panels and the power line.

"It's not an either-or," Crider said. "We need it all."

Contact staff writer Dave Downey at (760) 745-6611, Ext. 2623, or ddowney@nctimes.com.