U.S. grid facing blackout risks this summer and next winter, reliability agency warns
Energize Weekly, May 24, 2023
U.S. power grids are facing a risky summer and an even riskier winter, according to analyses by the North American Electric Reliability Corp. (NERC), the agency that oversees grid reliability and security.
While most of the U.S. has adequate resources for projected peak summer electricity demands, two-thirds of the country is in jeopardy of blackouts in the face of prolonged heat waves.
“If summer temperatures spike and become more widespread, the U.S. West, Midwest, Texas and Southeast United States, New England and Ontario may experience resource shortfalls,” NERC concluded in its summer reliability assessment.
When the summer is over, utilities and grid operators may face even bigger challenges as NERC has issued an unprecedented Level 3 alert – the corporation’s highest severity level.
In issuing the alert – with a list of steps grid operators should take in advance of the winter – NERC cited Winter Storm Uri in 2021 and Winter Storm Elliott in 2022, which both resulted in blackouts affecting millions of households.
“When cold weather events such as Winter Storm Uri occur, system operators may need to shed firm customer load to prevent uncontrolled load shedding and cascading outages which may not only result in major disruption but also have very real human consequences,” NERC said.
NERC developed a new set of cold weather reliability standards, which became effective on April 1, 2023. The Level 3 alert also set out eight initiatives grid operators and utilities should take.
These included calculating an “extreme cold weather temperature” for their preparedness plans and using that temperature to identify units that may require additional “freeze protection measures.”
Before the freezes, however, a broad swath of the country from Alaska to Florida to New England will face hotter than average summer temperature, according to the National Oceanic and Atmospheric Administration (NOAA). The only regions to escape the heat wave will be the Plains states and the upper Midwest.
The Southwest – centered on Arizona and New Mexico – faces the highest probability with a 60 to 70 percent chance of above-average temperatures. From Texas to New England, the odds of a warmer summer are 50 to 60 percent.
While the demand for cooling will be a major factor in determining grid performance, there are others, NERC said, including the loss of some fossil-fuel generation and the question of how well renewable resources, such as wind and solar, perform.
For example, NERC said for the Midcontinent Independent System Operator, which runs the grid across 15 Midwestern states and the Canadian province of Manitoba, “wind generator performance during periods of high demand is a key factor in determining whether there is sufficient electricity supply on the system to maintain reliability.”
There are no “high-risk” areas in this year’s assessment, but the number of areas identified as being at elevated risk has increased.
“We are facing an absolute step-change,” NERC’s Director of Reliability Assessment and Performance Analysis John Moura said in a media call. Over the past five years, Moura said, NERC has seen a “steady deterioration in the risk profile of the grid.”
