The Arkansas Public Service Commission on July 14 approved a March 23 application from Arkansas Electric Cooperative Corp. (AECC) for a Certificate of Public Convenience and Necessity (CCN) to construct, own, and operate a new 161-kV tap switching station and a new 7.3-mile 161-kV transmission line.
These projects would provide a new wholesale power and an energy delivery point to AECC member Craighead Electric Cooperative Corp. (CECC). CECC will be constructing a new distribution substation identified as the Gainesville 161-13.2 kV Substation. CECC will take wholesale delivery at the Gainesville Substation to provide distribution service to its members. Construction of the Gainesville Substation does not require a CCN.
The initial site work for the Switching Station is scheduled to begin in July, assuming the project has received commission approval, to be followed by installation of steel structures and bus-work during August, September, and October. Work on the remainder of the Switching Station will continue through December, with testing and checkout expected to be in January 2017.
Clearing of the transmission line right-of-way (ROW), which is needed on less than half the route, is also scheduled to begin in July 5. Installation of the structures is planned to occur in September, October, and November. Installation of the conductor, and testing and checkout would occur in late October and into December, with an in-service date of Jan. 24, 2017.
CECC currently serves approximately 10 MW of load in the Gainesville area with future load growth anticipated. These new facilities will bring a transmission source into CECC’s Gainesville area for service to this 10 MW load center.
Currently, the Gainesville area is served by long distribution circuits from wholesale delivery points at Crowley’s Ridge, Halliday, and Marmaduke Substations, which presents a challenge to CECC to maintain adequate voltage levels. The new transmission source provided by these new facilities will result in much improved voltage support for the area.
Additional benefits of these facilities will be increased reliability, reduced delivery losses, and the transfer of 10 MW of load from the existing Crowley’s Ridge, Halliday, and Marmaduke Substations, providing additional capacity at those locations for future load growth.
This project was submitted to the Midcontinent ISO as a part of MTEP 15 ("MISO Transmission Expansion Plan 2015"). The project received MISO approval in December 2015. The project was identified as Project ID 8480, Gainesville 161/13.2 Substation.
The Switching Station will connect to Entergy Arkansas Inc.‘s existing Paragould to Jim Hill Plant 161 kV transmission line about three miles south of Marmaduke, Arkansas. The Switching Station consists of three 161 kV circuit breakers, foundations, support steel, electrical bus work, a control building, and associated high voltage metering and switching equipment.
The Switching Station will be designed for a ring bus to allow increased reliability, as required by Entergy Arkansas for such connections, and will be built on a site approximately 7.5 acres in size.
The Transmission Line will be designed and operated at 161 kV and extend approximately 7.3 miles, generally west, to terminate at the CECC Gainesville Substation. The line will be supported by single weathering steel poles with guying required at angle structures.