Virginia Electric and Power d/b/a Dominion Virginia Power’s four proposed 500-kV transmission lines in Brunswick and Greensville counties in Virginia received a boost following a favorable report by the Virginia State Corporation Commission (SCC) staff.
In March 27 prefiled staff testimony, SCC staff found that the lines, as well as two 500-kV switching stations, are needed to interconnect the company’s proposed 1,358-MW – nominal – Brunswick County power station (Brunswick), for which the company requested a certificate of public convenience and necessity (CPCN). The company has also requested a CPCN for the transmission project.
“The staff concludes that the transmission project is needed in order to interconnect Brunswick and does not oppose the company’s choice of routes for the transmission project,” staff said.
The proposed Brunswick switching station would be connected to the collector bus of Brunswick by a 666-foot-long transmission line, the Brunswick County Power Station-Brunswick Switching Station Line #509. All output of Brunswick would flow through the attachment line and enter the company’s 500-kV transmission system at the Brunswick switching station.
That switching station would be connected to the company’s existing 500-kV transmission system through the other three new transmission lines, two of which would be 4.7-mile-long parallel lines that would form a transmission loop (Loop) to be inserted into the existing 500-kV Carson-Wake Line #570 at a point in Greensville County, 28.1 miles south of the Carson substation (Line #570 Junction), staff added.
The Loop would be built entirely on new right-of-way with a three-mile segment extending westward from Line #570 Junction in parallel with the company’s existing 115-kV Clubhouse-Chase City Line #71 to a point where Line #71 intersects the route of the proposed natural gas pipe line that is to supply the fuel for Brunswick, which point of intersection is known as “Freeman Junction.”
The proposed Rawlings switching station would be built at a point in the company’s existing Carson-Clover 500-kV line #556, 22.6 miles southwest of the Carson substation and provide a point of connection for the fourth new 500-kV line, Brunswick-Rawlings Line #591. This line would travel 13.5 miles, entirely on new right-of-way, to connect the Brunswick switching station to the Rawlings switching station.
Construction time for the estimated $89.1m transmission project will be about 24 months, with the target in-service date for Attachment Line #509 and the Loop being May 2015. The target in-service date for Line #591 is November 2015, and the target commercial operation date of Brunswick is May 2016.
The company chose a set of viable routes that could accommodate transmission lines from the Brunswick switching station to Line #556 and to Line #570, and from that set, chose two proposed routes.
Staff also said that the company’s preferred route for Line #591 is “Proposed Route D,” with a length of 13.5 miles, and it requires all new right-of-way. Proposed Route D begins at the Brunswick switching station heading northeast through forested areas and crossing Governor Harrison Parkway. Proposed Route D, which ends in the Rawlings switching station, lies totally within Brunswick County and crosses the company’s service territory for 1.41 miles, Southside Electric Cooperative’s service territory for 5.18 miles and Mecklenburg Electric Cooperative’s (MEC) service territory for 6.95 miles.
The company’s preferred route for the Loop is “Proposed Route C,” which is 4.7 miles long and requires all new right-of-way. It would be co-located with existing or future utility lines over its entire length as it parallels either an existing line or the proposed natural gas pipe line to Brunswick.
From the Brunswick switching station to Freeman Junction, Proposed Route C crosses the Norfolk and Western Railroad tracks, and then travels through mostly forested areas. The route is entirely within MEC’s service territory.
Staff noted that the company said its choice of Route D for Line #591 was based on it being the shortest and least expensive and it has relatively few residences within 500 feet of its centerline. Also, the company’s choice of Route C for the Loop is based on the route’s collocation with existing and proposed utility lines over its entire length, as well as crossing the least amount of wetlands.
As for the need, staff noted that in order for Brunswick to fulfill its role as a source of electrical energy to supply customer loads, Brunswick must be provided with an interconnection to the bulk power delivery system.
“Since the 115 kV transmission line adjacent to Brunswick does not have sufficient capacity to carry the output of Brunswick’s electrical generators, interconnecting transmission lines and switching stations must be constructed between Brunswick and existing high-capacity transmission,” staff said. “The interconnection must be of adequate capacity and reliability to qualify the power plant for full capacity rights within” PJM Interconnection.
In December 2011, PJM said the proposed interconnection was feasible and identified potential adverse impacts to the bulk power delivery system that might require mitigation by the company.
Among other things, staff said the company’s proposed route for the Brunswick-Rawlings line would require removal of 175.4 acres of upland forest and 3.1 acres of wetland forest, while the company’s proposed route for the Loop would require removal of 105.7 acres of upland forest and 1.2 acres of wetland forest.
The staff is concerned that no estimate or cap has been placed on the cost of forest loss mitigation, staff said, adding that any mitigation expense would ultimately be borne by ratepayers in the Dominion zone.
Dominion Virginia Power is a subsidiary of Dominion Resources (NYSE:D).