"This has been a huge project for this company, and, I might add, it's been a very successful project," said Matt Davis, vice president of distribution services for Nevada Power.

The Public Utilities Commission approved the project in 2001, the start of a new century, and it was named the Centennial projects.

Nevada Power proposed the project as a way to transport additional electricity to the explosively growing population in Las Vegas. At the time, it was in the midst of a Western energy crisis that sent wholesale prices soaring. The transmission lines help the utility import power from other areas and enable independent power producers in the area to sell some of their energy in other states.

The last phase runs 60 miles from the Harry Allen switch yard at the Apex Industrial Park, around the east side of the valley, and along a corridor followed by two existing transmission lines to the Mead Substation south of Las Vegas.

The Harry Allen-Mead transmission lines and related improvements will cost an estimated $118 million.

The company has obtained all of the required governmental approvals, with the exception of an environmental permit from the Public Utilities Commission. The PUC has scheduled a hearing in Las Vegas on Aug. 3.

If the commission gives Nevada Power a permit, Davis expects construction to start in the second half of 2005, with completion by early 2007.

The Centennial project originally was designed to provide transmission for new merchant power plants, including Pinnacle West Capital Corp.'s Silverhawk, Mirant Corp.'s Apex Generation Station and some projects that have been delayed or shelved.

The Centennial project would provide transmission capacity for 3,000 megawatts of electricity, but the Mirant and Pinnacle West projects together have only about 1,000 megawatts of power generation capacity, Davis said.

Nevada Power also will use some of the transmission capacity for its proposed 500-megawatt gas-fired plant and 75-megawatt gas-fired plant, both at Apex.

Nevada Power acted as general contractor for the project. It was the first time it designed and built 500-kilovolt transmission lines, one of the largest types of power lines now in use.

The electric company last year completed the 500-kilovolt Harry Allen to Northwest substation near Kyle Canyon Road. It also has finished the 500-kilovolt line between the Crystal Substation north of the Apex Industrial Park. A year ago, it installed two of the largest transformers in the world at the Crystal Substation.