NYISO finds deficit in reliability margins for NYC starting in mid-2025

In its quarterly assessment of reliability of the bulk electric system, the New York Independent System Operator (NYISO) found a deficit in reliability margins for the New York City area starting in the summer of 2025.

The deficit, driven primarily by the combination of a forecasted increase in peak demand and the unavailability of certain generators, could be as much as 446 megawatts (MW). According to NYISO’s Short-Term Assessment of Reliability (STAR) report, there were several factors driving New York City’s reliability need in 2025. The factors include increased electrification of the transportation and building sectors, continued economic growth following the pandemic, and the unavailability or retirement of select generators under the New York State Department of Environmental Conservation’s emissions limits.

“This new STAR report reflects the extraordinary challenges of the grid in transition,” said Zach Smith, NYISO’s vice president of System and Resource Planning. “The reliability of the electric system is essential to the health and safety for all New Yorkers as well as the state’s economy.  The NYISO will now work to identify solutions to the reliability need identified in New York City.”

The reliability need is based on a deficiency in transmission security, or the ability of the power system to withstand disturbances, such as electric short circuits or unanticipated loss of a generator or a transmission line. The NYISO first identified rapidly declining reliability margins in its 2021 Comprehensive Reliability Plan and restated those concerns in 2022.

Reliability rules that determine the acceptable levels of transmission security are determined by several entities that are responsible for overseeing the reliability of the bulk electric system. These entities include the North American Electric Reliability Corporation, the Northeast Power Coordinating Council, the New York State Reliability Council, and the New York State Public Service Commission.

The finding of a reliability need initiates a process administered by the NYISO to bring reliability margins back to acceptable operating levels. The NYISO will begin the process immediately by working with the local utility and the marketplace to identify and evaluate possible solutions.

Beyond 2025, the STAR report found that New York City’s reliability margin would improve when the Champlain Hudson Power Express (CHPE) transmission line from Quebec to New York City enters into service in the spring of 2026.