Planning Committee

Stakeholders Endorse Changes to 300-MW Load Loss Criteria

VALLEY FORGE, Pa. — The Planning Committee endorsed revisions to Manual 14B to specify that the 300-MW load loss to be considered in transmission contingency analyses applies only to losses affecting a large number of customers.  

PJM’s Stan Sliwa said the change is meant to address the growth of data centers and other large load customers, which can cause a single large customer to surpass the 300-MW threshold in PJM’s reliability planning criteria.  

The proposed manual changes specify the requirement applied to load loss “impacting numerous customers” and states that the limit is not applicable to “contingencies impacting several customers that aggregate to 300 MW or higher.” 

The proposal also would grant PJM discretion to permit load loss above 300 MW on a case-by-case basis, which PJM Director of Operations Planning Dave Souder said is meant to build on the goal of targeting outages affecting a large area. 

Transmission Expansion Advisory Committee

Two Generation Deactivations Being Studied

PJM is conducting reliability analysis of two generators that have filed deactivation notifications: the 844-MW H.A. Wagner generator, owned by Talen, and the 180-MW Warrior Run Unit 1, owned by AES.  

PJM’s Perry Ng said a preliminary analysis found the retirement of the Wagner plant, which can run on coal, natural gas, and oil, would cause reliability violations. Talen has requested to take the plant offline on June 1, 2025,  

The study assumed the continued operation of Talen’s 1,295-MW Brandon Shores coal plant, whose scheduled retirement is expected to require $786 million in transmission upgrades. (See “Brandon Shores Deactivation to Require $786M in Grid Upgrades,” PJM PC/TEAC Briefs: June 6, 2023.) Both generators are sited in the Baltimore Gas and Electric transmission zone. 

The Warrior Run retirement is not expected to prompt any reliability concerns, Ng said. He said the completed analysis of the 4-MW Trent generator deactivation request found no issues. 

Supplemental Projects

FirstEnergy has revised its proposed solution to replace an aging transformer at its Homer City North 345/230-kV substation because the equipment won’t be available for over a year beyond the desired in-service date in December 2023 due to backlogged procurement schedules. The original $6.6 million project would replace the transformer with a new unit rated at 691/854 MVA and install an auxiliary 230/23-kV transformer; the new proposal would use a higher rated 913/1,147-MVA transformer and drop the auxiliary component. 

Commonwealth Edison presented a $24.1 million project to replace a 345/138-kV autotransformer and capacitor bank at its Des Plaines substation, where mechanical issues have caused the transformer to be taken out of service periodically. The project has an in-service date of Dec. 31, 2025.  

PECO presented a $18.2 million project to rebuild two 96-year-old lines nearing their end of life: the 2.5-mile Plymouth Meeting-Flint 230-kV double circuit line and the Plymouth Meeting-Upper Merion 230-kV double circuit line. The Plymouth Meeting-Flint project has an estimated cost of $18.2 million, while the Plymouth Meeting-Upper Merion work has a $29.2 million cost. The projects also involve upgrades at the three substations. 

Public Service Enterprise Group presented a $105.1 million project to build a greenfield 69/13-kV substation, named Harlingen, in Hillsborough, N.J., to address rising loads at its Sunnymeade and Mount Rose substations. The substation would be cut into the Bennetts Lane-Montgomery 69-kV line and the Montgomery-Customer Sub 69-kV line. The work also includes the addition of a second 230/69-kV transformer at the Bennetts Lane substation and modifications to the buses at that facility. 

Dominion has updated a $55 million project to interconnect a new substation, Germanna, to serve a data center complex in Culpeper County, Va., with a projected 124-MW load. The substation would be cut into the Cirrus-Gordonsville 230-kV line, with an in-service date of April 16, 2026. 

AEP presented a $116.7 million project to rebuild 19 miles of its Marysville-Hyatt double circuit 345-kV line due to aging infrastructure, concerns of core corrosion and difficulty finding replacement parts. The utility stated it has about 570 miles of “paper expanded/air expanded” line rated at 345-kV in its footprint which will need replacement over the next 20 years. The Marysville-Tangy line has experienced two “permanent” and three “momentary” outages. 

AEP also presented a need for a serving a new 1,500-MW data center customer in New Carlisle, Ind., with a requested in-service date of Dec. 15, 2026.