PJM has asked Talen Energy to delay the retirement of two units at the fossil-fired Herbert A. Wagner Generating Station in Maryland until transmission upgrades are in service.

PJM cited concerns about reliability impacts the retirement of Wagner Units 3 and 4 would cause.

“PJM and the affected Transmission Owner performed a study of the Transmission System and found reliability concerns (wide area voltage drop and thermal violations in several transmission zones) resulting from the deactivation of these generating units,” the RTO told Talen in a letter Jan. 4.

In October, Talen Energy told PJM it planned to retire the 834 MW Wagner plant, which consists of three oil-fired units and a natural gas combustion turbine unit, as of June 1, 2025, citing environmental permitting and economic reasons.

But PJM is urging Talen to wait to retire Units 3 and 4 until the 2028 timeframe, when it said the transmission upgrades would be completed. According to the RTO, these upgrades were part of a solution identified to address reliability violations following the announced retirement of the adjacent 1,295 MW Brandon Shores facility, also owned by Talen and also requested to deactivate on June 1, 2025.

The Wagner retirements will not warrant additional upgrades, PJM said. These issues are being addressed by a set of proposed projects (PDF) that would expand the regional transmission system to accommodate electricity demand growth, generator retirements and future capacity needs.

PJM requested that Talen continue to operate Wagner units 3 and 4 under a Reliability Must Run (RMR) arrangement until the planned upgrades are completed. Talen is requested to respond in 30 days.

While PJM cannot compel a unit to remain in service, it can formally request that the owner continue operating the unit to support reliability. This process, detailed in Part V of the PJM Open Access Transmission Tariff, offers a deactivating unit the opportunity to remain in service and recover its operating costs until all necessary transmission upgrades are in place.

The H.A. Wagner station is located outside of Baltimore in Anne Arundel County, Maryland.

The 359 MW Wagner Unit 3 was completed in 1966 as a coal-fired unit that Talen converted to run on fuel oil at the end of 2023. Unit 4, commissioned in 1972, is a 415 MW oil-fired unit. Wagner Unit 1 is a 133 MW natural gas-fired unit that was built as a coal-fired unit in 1956. Talen retired the 136 MW coal-fired Wagner Unit 2 in 2020.

In explaining the need to retire Wagner Units 1, 3 and 4, Talen Energy said the “limited run hours on the Wagner Facilities are not sustainable to continue operations, especially in light of the amount of time the Wagner Facilities have recently been running in the market.”

Talen said the Wagner Facilities’ Title V air permit limits operation to capacity factors under 15% when operating on oil.

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