Idaho Public Utilities Commission

Case No. PAC-E-08-03, Order No. 30597

August 14, 2008

Contact: Gene Fadness (208) 334-0339, 890-2712


Commission seeking comment on proposed transmission project


The Idaho Public Utilities Commission is taking comments through Sept. 18 on Rocky Mountain Power’s request to build a 345 kV transmission line in Bannock and Oneida counties as well as a new substation in Downey.


The transmission line portion of the project would extend from an existing substation southwest of the Salt Lake City airport north to the new substation at Downey.


Rocky Mountain Power, which serves customers in southeastern Idaho, Utah and Wyoming, claims the expansion is needed to meet “significant increases in retail load” and to enhance reliability in the entire region. The line would also provide increased transfer capability of power between the company’s eastern (Oregon, Washington and northern California) and western (Idaho, Utah and Wyoming) control areas. If approved, the project would accommodate the delivery of power from the Goshen wind project in Bingham County as well as future power projects the company anticipates to build in Idaho and Wyoming. Increased transmission capacity gives utilities more options for cost-effective power supply sources, either through the utility’s own generation or from generators on the wholesale market.


Rocky Mountain Power has secured franchise agreements permitting construction within public thoroughfares and has applied with local government agencies for land use authorizations. The company estimates the project will increase its revenue requirement from Idaho customers by about 3 percent that could be applied in a future rate case.


According to testimony the company provided the commission, the existing transmission capacity from southeastern Idaho into Utah is fully utilized and no additional capacity can be made available without the addition of transmission lines.


The company is applying for a Certificate of Public Convenience and Necessity (CPCN), which is typically required by the commission before a regulated utility begins construction on a generation plant or transmission line. Because Rocky Mountain Power’s proposed transmission line is already inside its certificated area, a CPCN isn’t required. However, utilities may file an application for a CPCN to obtain the commission’s assurance that the utility may eventually recover the costs of typically large investments. When the company obtains a CPCN, it means the company has adequately demonstrated to the commission’s satisfaction that the new facilities are necessary.


The commission’s role is to determine if the project is needed to serve customers, meet load requirements and increase reliability. The commission will also examine the cost-effectiveness of the proposal. The commission does not have primary responsibility in siting decisions. Local governments (cities and counties) exercise primary authority over land-use decisions. Through a series of public information sessions, the company has been working with local government officials and citizens to address the route of the transmission line and the siting of the distribution station. The line has been re-routed to address citizen concerns.


The commission is seeking comments from customers that address topics such as: 1) Is the project needed to serve customers? 2) Will the project increase reliability and contribute toward fewer outages? 3) Will the project benefit customers by enhancing the utility’s ability to access other generation sources to meet customer demand? 4) Is the project cost-effective?


The commission intends to proceed under a modified procedure that allows this case to be handled through written public comments rather than by public hearing. However, comments may request a public hearing.


Comments are accepted through Sept. 18 via e-mail by accessing the commission’s homepage at and clicking on "Comments & Questions." Fill in the case number (PAC-E-08-03) and enter your comments. Comments can also be mailed to P.O. Box 83720, Boise, ID 83720-0074 or faxed to (208) 334-3762.


A full text of the commission’s order, along with other documents related to this case, is available on the commission’s Web site. Click on “File Room” and then on “Electric Cases” and scroll down to the above case number.