Entergy‘s Entergy Arkansas on Jan. 29 filed with the Arkansas Public Service Commission an application for a certificate of public convenience and necessity to build, operate and maintain a new 500-kV substation and associated facilities in Craighead County, Ark.
The company said it proposes to build and operate the new 500/161-kV transmission substation and related transmission line terminal facilities to be located near Jonesboro. The proposed electrical facilities will be built on lands purchased and owned by Entergy Arkansas and/or on existing transmission line right of way (ROW), the company said, adding that only minimal additional ROW may be required for possible guy wire clearances for the four transmission line segments terminating into the proposed substation site.
The design of the proposed electrical facilities will consist of Entergy Arkansas’ standard 161-kV switchyard and a 500-kV gas insulated substation that will be built near the intersection of three existing Entergy Arkansas transmission lines, the Independence Steam Electric Station (ISES) to Dell 500-kV transmission line, the Jonesboro Hergett to Jonesboro transmission line, and the Jonesboro Hergett to Trumann 161-kV transmission line. The company added that the location of the proposed substation is on an 80-acre site owned by Entergy Arkansas about 2.5 miles southeast of Jonesboro. The property required for the construction of the 500/161-kV substation will be about 11 acres.
The company added that six new transmission line segments will be terminated into the new proposed substation:
· ISES to proposed substation 500-kV transmission line
· Proposed substation to Dell 500-kV transmission line
· Jonesboro to proposed substation 161-kV transmission line
· Proposed substation to Jonesboro Hergett 161-kV transmission line
· Jonesboro Hergett to proposed substation 161-kV transmission line
· Proposed substation to Trumann 161-kV transmission line
The company noted that operation of the proposed electrical facilities would be coordinated by the System Operations Center via supervisory control with oversight by the Midcontinent ISO.
The proposed substation site was purchased in coordination with the planning and construction of the ISES to Dell line, which was placed in service in 1984; it was purchased in anticipation of a future 500-kV connection to the high voltage grid in the northeast service area near Jonesboro, a growing load center, the company said.
The proposed electrical facilities are needed to enhance transmission voltage levels in the area and to increase the operational reliability for Entergy Arkansas’ transmission grid located in the northeast part of the company’s service area, specifically Craighead County.
The project is a reasonable approach for providing safe, reliable electrical transmission service for northeast Arkansas; would provide operational flexibility between the 161-kV and 500-kV transmission grids for delivering power to the expanding load in Jonesboro; and would enhance the reliability and voltage support by providing a 500-kV source in the area, according to the company.
The total estimated investment in the proposed electrical facilities is about $55.9 million, which compares to the company’s total transmission and substation plant in-service balance of about $2.03 billion as of Dec. 31, 2014. The company also said that it would finance the construction with funds available from various sources, including retained earnings, debt and capital securities.
The company said that once operational, the proposed electrical facilities would have little, if any, adverse impacts on the surrounding environment. The transmission design proposed is aesthetically appropriate and would consist of facilities that are maintained by periodic inspection in accordance with current vegetation specifications, the company said.
The proposed electrical facilities would not impact state parks or federal lands, nor would it materially impact state and national scenic byways, wildlife management areas, or similar sensitive areas or attractions, the company said.
According to the direct testimony of Gerald Sachitano Jr., manager, capital projects in the Capital Projects Management and Technology Organization of Entergy Arkansas affiliate Entergy Services, should the commission approve the CCN, final substation site work would be completed in 3Q16.
Substation foundation work for the 500-kV switchyard and the 161-kV switchyard, and related electrical equipment, would be completed in 4Q16.
Sachitano also said that installation of 500-kV and 161-kV electrical equipment, autotransformer, and gas insulated switchgear would start in 1Q17, with termination of 500-kV and 161-kV transmission lines beginning in 2Q17.
Final substation and transmission line construction, testing and electrical check-out would be completed in 4Q17. The in-service date for the proposed electrical facilities is scheduled for November 2017, Sachitano added.