District of Columbia regulators have approved Potomac Electric Power’s (Pepco) plans to upgrade two underground transmission circuits.
According to the District’s Public Service Commission (PSC), Pepco intends to replace the existing conductor for two circuits with a larger conductor, and increase the voltage on one circuit from 138 kV to 230 kV. The second circuit would be maintained at its existing 230-kV voltage.
“[T]he commission finds that Pepco has sufficiently demonstrated the reasonableness, safety and need for underground transmission lines,” the PSC said, adding that construction can proceed under permits the company received from other city agencies.
On Jan. 6, Pepco filed a notice to upgrade two underground transmission circuits in excess of 69 kV, noting that the project is needed to maintain the electric system’s reliability and to ensure the continuity of electric supply to customers.
The PSC also said that according to the company, the project involves upgrading a 138-kV underground transmission line – starting on March 14, 2013, with a completion date of May 2014 – and a 230-kV underground transmission line – starting on Sept. 15, 2012, with a completion date of March 2013 – between the Buzzard Point generating station in the southwest portion of Washington, D.C., and Pepco’s Ritchie substation No. 123 in Seat Pleasant, Md.
Pepco also said that PJM Interconnection’s (PJM) Transmission Advisory Committee (TEAC) has identified the project as a solution to resolve reliability problems as a result of the thermal overloads and the retirement of the Buzzard Point generating station. The company further noted that the capacity increases for the circuits are required to meet NERC reliability standards for bulk electric systems facilities.
Among other things, the PSC said that based on the record, no party directly contests the fact that the PJM/TEAC has identified the project upgrades as required to resolve future load demand and system reliability problems due to the retirement of the Buzzard Point generating station.
There has also been no challenge to the dates of Sept. 15, 2012, and March 14, 2013, when the projects must begin in order to achieve the necessary in-service dates of March 2013 and May 2014, respectively.
“Given the problem created by the retirement of electric generating facilities in the District, and the future increase in load demand and reliability requirements, the commission finds that Pepco’s proposed upgrades are necessary,” the PSC added.
Pepco is to file quarterly reports updating the PSC on activities pertaining to the replacement of the conductor and the upgrades to the 230-kV underground transmission lines in the District.
Pepco is a subsidiary of Pepco Holdings (NYSE:POM).