Increased electricity demand and reduced generation capacity present “unprecedented” threats of power shortages and disruptions this winter in several regions of the country, particularly during widespread and sustained frigid weather, the North American Electric Reliability Corp. said Thursday.

NERC’s annual winter reliability assessment says inadequate generation weatherization, fuel supply risks and a shortage of natural gas pipeline capacity could lead to mandatory conservation, rolling service curtailments and potentially life-threatening power outages in several regions.

“This assessment paints a stark and disheartening picture of the reliability challenges facing more than half of the United States this winter,” said NRECA CEO Jim Matheson.

NERC’s report, which covers the period of December through February, says reserve operating generation capacity has fallen by 5% from last winter’s levels as periods of extreme weather become more frequent.

“The bulk power system is impacted year after year, more than it has ever been,” said John Moura, NERC’s director of reliability assessment. “Weather is the most influential factor. The grid has to constantly balance supply and demand.”

The report warns that consumers in the Upper Midwest and Great Lakes regions, parts of the Southeast and northern New England, and states bordering the western Gulf of Mexico could face the greatest risks, particularly if winter temperatures are harsher than expected.

Among the areas of most concern are parts of Texas served by the Electric Reliability Council of Texas and the 15 states from Louisiana to Minnesota served by the Midcontinent Independent System Operator. Georgia and the Carolinas, served by SERC Reliability Corp., face elevated risks due in part to limited natural gas transmission infrastructure in the region.

NERC is encouraging state regulators to take these actions to reduce power grid risks:

• Continue operation at electric generation assets slated for retirement.
• Support transportation waivers for shipping bulk fuels, including coal, liquified natural gas and fuel oil.
• Communicate regularly with power providers to ensure that they maintain adequate supplies of fuel to meet both normal and heightened demand during sustained periods of extreme cold.

NERC warns that prolonged summer heatwaves prompted some providers to delay seasonal maintenance and restrained their ability to build up fuel supplies for winter. The ongoing supply shortage impacting the production and distribution of transformers could also slow or stall system restorations following severe winter storms.

“Consumers face an inconceivable but real threat of rolling blackouts,” Matheson said. “Absent a shift in state and federal energy policy, this is a reality we will face for years to come.”

NRECA is among the energy industry interests urging policymakers to alter the current course of energy transition, which places speed over practicality, often emphasizing the growth of intermittent renewable energy without maintaining an adequate supply of always-available generation.

A recent report produced by the National Renewable Energy Laboratory concludes that a Biden administration goal of meeting a net zero-carbon grid by 2035 will require a threefold increase in electric generation above 2020 capacity levels.

NERC’s assessment encourages power producers, transmission organizations and regulators to enhance assessments and maintain ongoing communications to address reliability concerns, particularly during the most severe weather conditions.

Extreme heat and cold do not just boost demand for electricity, they also force delays or curtailments of fuel deliveries and maintenance to assets available to meet normal demand. The impacts on consumers include frequent calls for voluntary conservation, sporadic service disruptions and higher bills spurred by supplemental market purchases and delivery costs for power. In most cases, available generation capacity and transmission congestion are contributing factors.

“Electric cooperatives remain focused on working toward meaningful solutions to address reliability challenges spreading across the nation,” Matheson said. “This includes pressing for meaningful action to reform the process for permitting and siting new electric generation and transmission infrastructure.”