The four plants, owned by Astoria Generating Co, will stay operational beyond their planned retirement in May 2025, adding 508 megawatts (MW) to New York City's power reserves which otherwise be in a 446 MW deficiency.
"The reliability deficiency is being driven by increased demand for electricity, economic activity, and recent generator retirements per emissions requirements set forth by the New York State Department of Environmental Conservation (DEC)," the NYISO said.
DEC's "peaker rule," under which Astoria's four plans were going to shut down, has shut 950 megawatts of inefficient generation in environmental justice areas, with a provision to temporarily keep plants in operation to maintain reliable power supply.
In a two-month window, NYISO did not get any other solutions to fully meet the deficiency but said the supply situation for New York City will improve after new power lines expected to enter service in spring 2026 will connect it to 1,250 MW of hydropower in Quebec.
Rapid electrification is boosting power demand and straining the electric grid in New York state, as renewable resources struggle to replace fossil fuel that is being phased out, a June report by the grid operator found.
The grid needs to triple its clean energy supply to meet the state's goal of an emission-free electric system by 2040, but geopolitical issues, permitting uncertainties and global supply chain constraints are impeding investments, the report said.
Last winter in New York City, utility Consolidated Edison (ED.N) took emergency measures to avoid large scale outages.
