A Virginia State Corporation Commission (SCC) hearing examiner, in a March 10 report, recommended that the SCC grant Virginia Electric and Power’s d/b/a Dominion Virginia Power’s application to rebuild, entirely within its existing right of way (ROW), about 27.5 miles of its existing 500-kV Carson-Rogers Road Line #585 in Dinwiddie, Sussex, and Greensville counties.
The line – which went into service in or about 1972, shortly after the completion of Dominion’s 500-kV original loop – would be rebuilt from Structure #3 outside of the Carson switching station to Structure #142 located at a point north of the junction of Line #585 and Line #570, about 0.9 mile northwest of the company’s approved Rogers Road switching station in Greensville County, which is under construction.
According to the company, the hearing examiner added, the project is needed to assure that the company can continue to provide reliable electric service consistent with mandatory NERC reliability standards for transmission facilities and the company’s transmission planning criteria.
The line provides service to the company’s transmission system in the western and central regions of Virginia, and is a critical component of the electric transmission grid that serves Virginia, North Carolina, West Virginia, the District of Columbia, Maryland, and beyond, according to the company.
The hearing examiner also said that according to the company, the project resolves a generator deliverability criteria violation identified by PJM Interconnection. The company confirmed the PJM-identified generator deliverability N-1 violation on the Carson-Rogers Road line caused by the loss of the 500-kV Carson-Rawlings Line #511. The violation, the hearing examiner added, overloads Line #585 well above its thermal capacity, and the rebuild project is necessary to resolve that violation.
While the generator deliverability violation is projected to occur in 2020, the company is working to schedule outages starting next fall to accommodate construction completion by December 2018.
The company also said that failure to address the significant inherent corrosion and deterioration associated with “COR-TEN” weathering steel lattice towers would ultimately limit the company’s ability to maintain reliable transmission service to its customers.
The hearing examiner added that according to the company, the project has been reviewed through the PJM Southern Sub-Regional Committee and the PJM Transmission Expansion Advisory Committee, and approved by the PJM Board of Managers. Demand side resources were not considered because the driver for the project is generator deliverability, in addition to addressing aging infrastructure, the hearing examiner said.
The company also noted that, in connection with another case, it retained Quanta Technology to investigate the condition of the company’s original 500-kV “COR-TEN” towers and the need to rebuild them. The SCC initially approved the rebuild of the Carson-Rawlings Line (Line #551) in 2011, which is complete, and since that time, the SCC has approved or is pending approval in the rebuild of other segments of the 500-kV original loop.
The hearing examiner added that according to the company, the rebuild project would have three triple-bundled 1351.5 aluminum-conductor steel-reinforced (ACSR) phase conductors, arranged with two fiber optic shield wires. The rebuild project would uprate the existing Line #585 to a transfer capability of 3424 to 4330 MVA. According to the company, the hearing examiner added, the proposed lattice towers are similar to the existing weathering steel lattice towers.
The project’s estimated cost is about $52.9m, with about $52.6m for transmission line construction work and about $266,000 for station work at the Carson station (2016 dollars).
The hearing examiner further noted that according to the company, the project has been revised since its initial submission to PJM to incorporate refined forestry costs, currently estimated to be about $7.2m.
The company has also noted that the project’s in-service date is anticipated to be December 2018.
The hearing examiner added that SCC staff, in its report, concluded that since each of the four alternatives that the company provided to resolve the generator deliverability violation would require the construction of a new transmission line in a new ROW, each alternative would have a greater environmental impact than the proposed rebuild project. In addition, none of the four alternatives would address the structural deterioration of Line #585.
Staff also said that if the SCC determines that the company should mitigate the visual impacts of galvanized steel in the proceeding, then the use of the factory-dulled galvanized steel structures may be a cost-effective and reasonable means for such mitigation.
In its rebuttal, the hearing examiner added, the company opposed staff’s proposed option to use factory-dulled galvanized steel for the tower structures. The company noted, for instance, that the company has installed galvanized 500-kV lattice structures in the vicinity of the rebuild project within the last few years, and is not aware of any concerns expressed by the public or county officials regarding the initial reflectivity of those steel lattice towers since installation.
The hearing examiner found that there is a definite need for the rebuild project, noting, for instance, that staff determined that the company’s analyses are reasonable.
The hearing examiner also said that the recommendations contained in an October 2016 Virginia Department of Environmental Quality should be implemented by the company.
With those recommendations, “I find that the proposed rebuild project will have a reasonably minimal impact on the environment and scenic resources,” the hearing examiner said, adding that the company does not have any objections or concerns with the summary of the recommendations.
In addition, due to the time constraints, incremental cost, and potential maintenance issues, the hearing examiner said that he finds that a chemical dulling process should not be required for the rebuild project.
Dominion Virginia Power is a subsidiary of Dominion Resources (NYSE:D).