The North American Electric Reliability Corporation (NERC) says most of the continent should have enough electricity supply to meet expected winter demand, but continued load growth and fuel supply risks could create reliability challenges during prolonged cold weather.
“The bulk power system is entering another winter with pockets of elevated risk, and the drivers are becoming more structural than seasonal,” said John Moura, NERC’s director of reliability assessments and performance analysis, on a call with reporters this week.
NERC’s annual Winter Reliability Assessment (WRA) evaluates whether the bulk power system can meet peak demand from December through February. This year’s report highlights two major trends shaping winter reliability: rising electricity demand and a changing resource mix as more thermal plants retire and battery storage grows.
Across all regions, winter peak demand forecasts have increased by about 20 GW, or 2.5 percent, since last year. Nearly every region is reporting higher demand, with some approaching double-digit percent increases. New generation and storage additions offset some of that growth, but total resources increased by only 9.4 GW.
“All this tells us that we have a tightening of reserves as demand escalates and resources aren’t quite keeping pace,” said Mark Olson, NERC’s manager of reliability assessments.
A notable portion of new resources is coming from battery storage and demand response. More than 11 GW of new battery capacity and 8 GW of additional demand response were added since last winter, NERC said. These resources help operators manage peak conditions, but they also introduce operational challenges. Batteries must maintain adequate state of charge during long-duration cold events with limited solar availability, and demand response often comes with contractual limits on when and how long it can be used.
Under normal winter conditions, NERC expects all regions to have adequate resources to meet their 50-50 peak forecast. The risk grows when cold weather lasts for several days across large areas, driving up demand while stressing gas supply, renewable output and thermal plant performance.
The organization identified several regions with elevated risk if conditions turn extreme, including Texas, parts of the Southeast, New England and Eastern Canada and portions of the Western Interconnection. In many of these areas, rapid load growth is tied in part to data centers and industrial development.
Olson noted that round-the-clock loads are lengthening peak periods and leaving fewer hours to recharge storage and restore reserves.
“What we’re observing when we do all-hours energy risk analysis is a trend with expanding the risk hours of shortfalls, as the demand profile is flattening and covering more hours, and there’s less seasonality to it,” he said.
Natural gas availability remains a central reliability issue. As coal retirements continue, winter reliability depends heavily on gas-fired generation, particularly units that cannot switch to backup fuels.
Olson said gas production and delivery “strongly affect how well the bulk power system can perform during winter conditions.”
Although gas delivery performance has improved since Winter Storms Uri and Elliott, production still drops sharply during severe cold. NERC said most freeze-protection measures for the gas sector remain voluntary, creating uneven levels of preparedness.
New cold-weather standards bring improvements
New federal cold-weather standards, approved by FERC in late 2025, introduce the first mandatory requirements for generator freeze protection and winter readiness across the bulk power system. The standards, known as EOP-012-3, were developed in response to the widespread outages during Winter Storms Uri and Elliott and apply to all generator owners and operators.
The rules require units to identify freeze-vulnerable equipment, install mitigation such as heat tracing and insulation, and maintain cold-weather readiness plans that include inspections, verification steps, and operator training. Plants must also document corrective actions when they identify equipment failures or missing protections.
NERC says the industry has made measurable progress. Based on the first annual Cold Weather Data and Analysis report submitted in October, 96 percent of the nation’s winter capacity now reports extreme-cold temperature thresholds at or below 32 degrees Fahrenheit. Nearly 99 percent of winter capacity reports that it can operate at those temperatures when protections are deployed.
NERC considers this a significant improvement over the years following Uri, when inadequate insulation, frozen sensing lines, inoperable valves and poor documentation contributed to widespread forced outages.
The organization recommends that grid operators, utilities and generators review winter operating plans, complete weatherization activities early, monitor fuel supplies closely and prepare for the possibility that load forecasts may understate actual conditions during extreme cold.
