A new study from the Northeast Power Coordinating Council (NPCC) outlines some of the major risks that reliance on natural gas generation poses for the New England power system and emphasizes the need for dispatchable resources to limit potential winter reliability issues. 

NPCC, which conducted the study in coordination with NYISO, ISO-NE, NERC and the Northeast Gas Association, found the gas system to be “fully utilized” throughout a three-day modeled cold stretch. 

However, if the cold snap lasts beyond three days, or key gas network outages occur at the same time, it likely will add “significant stress to the consolidated network of gas pipeline and storage infrastructure in New England and New York,” said NPCC CEO Charles Dickerson, adding that an extended cold stretch could put significant pressure on the region’s oil inventory and replenishment capabilities. 

Additionally, extreme, low-probability events causing the “near or total cessation of natural gas throughput,” such as the outage of a key pipeline or compressor station, may cause “catastrophic impacts for downstream customers,” NPCC wrote. 

During normal operations, the Northeast faces significant gas constraints in the winter, when much of the pipeline system is reserved for heating needs. 

“Since most generators do not have firm transportation entitlements, the ability of pipelines to provide intra-day scheduling flexibility to accommodate the twice-daily ramp during cold snaps should be questioned,” NPCC wrote.  

As renewables proliferate, NPCC found the ramping requirements in both New England and New York could surpass 7,000 MW by 2032. It projected that the increasing ramping needs “can generally be accommodated” in the long term under normal weather conditions. 

New England’s “duck curve” has increased in recent years due to the rapid expansion of behind-the-meter solar. ISO-NE surpassed 100 duck curve days for the first time in 2024, which are defined as days when mid-day demand is lower than overnight demand.  

In the winter, the two major liquified natural gas (LNG) import terminals servicing New England — Repsol’s facility in St. John, New Brunswick, and Constellation’s Everett Marine Terminal (EMT) located just north of Boston — remain “an integral part of the gas-fired generators’ ability to satisfy fuel assurance objectives,” NPCC found.  

LNG deliveries from the facilities “give pipeline operators valuable scheduling flexibility since they displace the need for conventional flows west-to-east into New England,” NPCC added. It estimated the two facilities can provide enough LNG to fuel 8,000 MW of gas generation.   

While EMT is under contract with the Massachusetts gas utilities though May 2030, the future of the import terminal is uncertain after the contract expires. When the Massachusetts Department of Public Utilities approved the contracts in May, it directed the utilities to work to reduce or eliminate their reliance on the facility in accordance with the state’s climate goals. (See Massachusetts DPU Approves Everett LNG Contracts.) 

NPCC singled out the Everett terminal as a particularly important facility for gas and electric reliability, writing that it plays a key role that could not be filled easily by additional imports from St. John or increased oil generation.  

“EMT’s location is ideal because it provides both pressure support and flow on an instantaneous basis, whereas Repsol Saint John cannot,” NPCC wrote. Although Repsol could pack the Maritimes and Northeast pipeline in the hours before an expected need, its facility is not able to provide the same real-time reliability support as EMT, NPCC said.  

While oil generation theoretically could replace the 2,600 MW of gas generation capacity supported by EMT, oil retirements over the next decade, combined with the potential loss of EMT, may increase the likelihood of capacity deficiencies, NPCC wrote. 

The NPCC’s findings echo some of the key results from ISO-NE’s Economic Planning for the Clean Energy Transition (EPCET) study, which the RTO released in October. (See ISO-NE Study Lays Out Challenges of Deep Decarbonization.) 

The EPCET study emphasized the importance of maintaining an adequate amount of dispatchable generation on the grid to balance renewables and ensure reliability.  

“The grid of 2032 and beyond may sometimes require more dispatchable generation (either from stored fuels or an unconstrained fuel supply) than it has in recent winter conditions,” the EPCET study found.  

The EPCET study also found that the winter season likely will be the last to decarbonize due to factors including the high winter peak, need for dispatchable generation and high costs of existing clean firm generation resources.  

ISO-NE is overhauling its capacity market, with the intent of increasing compensation for resources that protect grid reliability during the most vulnerable periods. The reforms likely will add incentives for gas generators to contract for firm fuel, though it is unclear whether these incentives will change generator behavior.  

NCPP’s study also noted that offshore wind “has the potential to materially lessen reliance on oil and gas during the peak heating season.” Multiple New England states also are pursuing large-scale additions of battery storage, which should help lessen the reliance on gas to meet peak demands.  

“Uncertainty about the pace, amount and inevitability of electrification, electric vehicles and offshore wind in the years ahead may intensify operational stresses on the gas infrastructure available to serve gas-fired generation over the medium and long term,” NPCC concluded.