Exelon’s (NYSE:EXC) Baltimore Gas and Electric (BGE), in a July 7 filing submitted to the Maryland Public Service Commission (PSC), requested that the PSC waive the requirement to obtain a certificate of public convenience and necessity (CPCN) in connection with work on a portion of an existing 230-kV overhead transmission line in Baltimore and Harford counties in Maryland.
Noting that it is responsible for maintaining the safety and reliability of its electric transmission system and ensuring that PJM Interconnection can properly and reliably operate the interconnected system within the PJM region, BGE said that it must modify the existing line that runs between the Conastone substation in Baltimore County and the Maryland-Pennsylvania border in Harford County in order to address aging infrastructure and enhance system protection communications.
BGE said that it plans to start the construction work for the project in February 2018, and estimates that it would take about four months to complete the project.
Describing the need for the project and scope of work, BGE said that Circuit No. 2302 is an existing overhead line that runs from the company’s Conastone substation to PPL (NYSE:PPL) subsidiary PPL Electric Utilities’ Otter Creek substation in York County, Pa. Recently, PPL modified the portion of Circuit No. 2302 that runs between the Maryland-Pennsylvania border and the Otter Creek substation. BGE added that PPL installed optical ground wire (OPGW) from the Otter Creek substation up to the point of transition between the BGE and PPL systems at the Maryland-Pennsylvania border.
Currently, there is no OPGW that runs from the Conastone substation to that system transition point, BGE said, adding that installation of OPGW is integral in supporting, redundant, reliable system protection communication for the interconnected electric transmission system.
The overhead line that runs between the Conastone substation and the Maryland-Pennsylvania border was originally installed in the 1930s, the company said, noting that the tower structures that support the line along the approximately 1.7-mile stretch between Gorsuch Mills and the Maryland-Pennsylvania border have not been replaced since the original installation.
Upon completion of the project, a seamless OPGW path would exist between the Conastone substation and the Otter Creek substation, the company noted.
As part of the project, BGE said that it would replace six steel lattice towers with 10 weathering steel poles along the approximately 1.7-mile section of Circuit No. 2302 between Gorsuch Mills and the Maryland-Pennsylvania line. The additional four structures are necessary to maintain compliance with National Electric Safety Code and BGE internal design load criteria, the company said.
The replacement pole structures would range in height from about 115 feet to 165 feet with a base diameter of about 62 inches tapering to about 31 inches at the top of the pole, BGE said. The existing steel lattice tower structures along Circuit No. 2302 between the Conastone substation and the Maryland-Pennsylvania line range in height from about 86 feet to 184 feet, the company noted.
BGE said that it would install OPGW in the shield wire positions at the top of the existing and replacement structures that run from the Conastone substation to the Maryland-Pennsylvania border.
The company also noted that it would replace the conductor between Gorsuch Mills and the Maryland-Pennsylvania border with 1590kcm 54/19 ACSR “Falcon” conductor to match the approximate 1.5-inch size of the conductor between the Conastone substation and Gorsuch Mills, creating conductor size uniformity along the entire stretch of the line.
BGE noted that the statutory requirements for obtaining a mandatory waiver of CPCN requirements from the PSC are satisfied as all of the work with the project relates to an existing overhead line designed to carry a voltage in excess of 69 kV; in order to build the project, BGE will not need to obtain any new real property or additional rights of way through eminent domain, as all of the work would take place within the existing BGE transmission corridor; and BGE would not install any larger or higher structures as part of the project.