Rocky Mtn. Power plans 1,200 miles of new lines

Rocky Mountain Power said Wednesday that it will build more than 1,200 miles of high-voltage transmission lines to carry electricity from Wyoming to Utah, Idaho, Oregon and parts of the Southwest.

The $4 billion project involves two 500-kilowatt lines.

Construction will start this year and finish sometime in 2014, the company said. The cost of the lines would be passed on to customers in power rates sometime between 2014 and 2016.

Right-of-way acquisition for the lines has already started, according to Dave Eskelsen, a spokesman for Rocky Mountain Power. Financing for the lines could involve a combination of means, including cash from Portland-based PacifiCorp, the parent company of Rocky Mountain Power; equity support by MidAmerican Energy Holdings, which owns PacifiCorp; or commercial financing.

"You can build all the generation you want, but if you don't have the transmission at work you can't get it from place to place," Eskelsen said. "Particularly if we want a very robust investment in wind power, transmission is absolutely essential to that."

PacifiCorp said it has reached an agreement with Idaho Power Co. to cooperate on the northernmost line, a double-circuit line from the Jim Bridger power plant in Wyoming to southeastern Idaho, with a connection into Utah along an existing transmission path.

Another segment of this line will be built west across Idaho and into Oregon.

The 600-mile line will be capable of delivering up to 3,000 megawatts of electricity from Wyoming to Idaho into Utah and up to 2,500 megawatts of new capacity from Idaho west into Oregon.

A megawatt is enough electricity to power more than 500 typical homes.

The second major line will run from southwestern Wyoming, near the Jim Bridger power plant near Rock Springs, into central Utah at the Mona substation located in Juab County, the company said. This line will then extend from the Mona area into southern Utah and the desert Southwest. It will be capable of delivering up to 3,000 megawatts from Wyoming to Mona, and 3,000 megawatts from the Mona area into the Southwest.

The lines will be the first major projects to be built under the oversight of the Northern Tier Transmission Group, which will oversee the planning of the two lines and manage the public input process.

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