CARSON CITY — For years, utility industry executives and regulators have longed to have one transmission line that directly connected Nevada Power Co. of Las Vegas with Reno-based Sierra Pacific Power Co.

The two companies, now both known as NV Energy, have been isolated from each other although they are part of the same holding company, NV Energy Inc.

A few weeks ago, LS Power of East Brunswick, N.J., was approved to build a transmission line on the east side of Nevada linking Las Vegas with transmission lines near Ely that run to Reno. LS Power hasn't said whether it can sell enough transmission capacity to make the line feasible.

Now, Vulcan Power Co. of Bend, Ore., wants to build a second line on the west side of Nevada.

Vulcan wants state approval to build a 347-mile, 500-kilovolt transmission line that would run from Yerington in the north to Jean in the south, giving Las Vegas and Southern California access to geothermal power resources in northern Nevada.

NV Energy continues to plan its own transmission lines on both sides of the state, spokesman Adam Grant said.

Vulcan is seeking Public Utilities Commission approval under the state's Utility Environmental Protection Act. Separately, the company has applied to the federal Bureau of Land Management for a 200-foot right of way.

The transmission line would interconnect with Vulcan's planned line that would run from Fernley to Bishop, Calif. The Fernley-Bishop line is undergoing environmental review, and Vulcan expects to start building it later this year.