Officials with PJM Interconnection said a coal-fired power unit in Delaware can be closed two years ahead of schedule. The grid operator this month announced the Indian River Unit 4, a 411-MW generator in southern Delaware owned by NRG, can be taken offline without negative impacts to power reliability. The Indian River plant, located in Sussex County and which at one time operated four coal-fired units, first came online in 1957.
PJM in an announcement said Delmarva Power, which owns regional transmission, has completed system upgrades supporting grid reliability, enabling the coal-fired unit to shut down 22 months ahead of its scheduled decommissioning date. Delmarva Power on Dec. 18 said it had completed the Vienna-Nelson line upgrade, the last piece of transmission upgrades that will allow Indian River 4 to be retired without creating grid reliability issues.
NRG in June 2021 told PJM it wanted to retire Indian River 4 by June 2022. PJM conducted an analysis of grid reliability and at that time said closing the unit would create issues for grid. The grid operator identified several possible transmission upgrades to address those issues, and said it estimated those upgrades could be completed by year-end 2026.
PJM in a formal request asked NRG to keep Indian River 4 online under a Reliability Must-Run, or RMR, agreement while those upgrades were being completed. NRG agreed to maintain the coal-fired unit under a rate schedule that was approved by the Federal Energy Regulatory Commission. PJM has notified NRG of its intent to terminate the RMR arrangement with the grid upgrades completed.
The RMR will officially end in February of next year, or 22 months prior to the original end-date of December 2026. That will enable a savings of about two years of RMR payments, estimated at about $93 million according to the settlement rate filed with FERC.
“Delmarva’s good work to complete this project far ahead of schedule is a win for our customers, both from a reliability and affordability perspective,” said Mike Bryson, senior vice president-operations at PJM, in a statement. “PJM regards RMR arrangements as a last resort to keep units temporarily operational to maintain system reliability while we make transmission improvements to balance the system, so the sooner we can get the work done, the better.”
Unit 4 at Indian River entered commercial operation in 1980. Units 1 and 2, each with about 82 MW of generation capacity, were retired in 2013. The 177-MW Unit 3 at the site was taken offline in 2014.
—Darrell Proctor is a senior editor for POWER.
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