POWER LINES Summer forecast: Sunny and hot with a chance of

BY AMY HOWAT

In June of 2022, after fierce storms ripped through the region, areas in and around Columbus were hit with power outages. Residents flocked to cooling centers as temperatures soared into the 90s. Animal shelters begged for donations of ice to relieve overheated dogs, and two local hospitals ran on backup generators.

Six months later, during the bitter chill of Winter Storm Elliott, consumers in Kentucky and eight other states experienced interruptions to their electric service.

In both cases, many of the outages were not due directly to the extreme weather events, but were mandated by the regional grid operator to quickly reduce electricity consumption and maintain the necessary balance between supply and demand.

That emergency balancing act is known by many names, including “intermittent outage” or “forced outage,” but is most commonly called a “rolling blackout.” It can happen when a peak in electricity use — usually during extremely hot or extremely cold weather — coincides with significant gaps in the generation or transmission of electricity, says Ben Wilson, director of power delivery engineering for Buckeye Power, which supplies electricity to Ohio’s electric cooperatives.

“It’s always a possibility, but it takes a perfect storm of factors converging to get us to that point,” Wilson says.

What do they mean?

“Rolling blackouts are a last resort when the normal lines of defense have failed.”

Rolling blackouts reduce demand on the stressed electrical grid to prevent wider outages. “We could be called upon to reduce, say, 5% of load or we all risk blackouts,” he says. “Co-ops have plans in place if this happens. We’re not going to cut power to hospitals or prisons. If it’s going to be sustained, we’ll cycle it, restoring power to some areas while cutting it somewhere else.”

The good news is that rolling blackouts happen rarely. The bad news is that a convergence of factors, including increased electrification and reduction in reliable power generation, is reducing the surplus of available electricity, closing the gap between supply and demand.

“The risk is higher now than it was five years ago, and it will continue to be elevated until more generation comes online,” Wilson says. “In the next three to five years, at least, we’ll be living with that elevated risk in summer and winter months.”

The North American Electric Reliability Corporation, an industry organization charged with assessing and improving the reliability of electricity, has warned of an elevated risk of electricity shortfalls for about twothirds of the U.S. this summer during periods of low wind or drought along with extreme temperatures.

Outage: Any loss of power to an area is an outage. The vast majority of outages are unplanned and limited to a specific area. Most are caused by trees hitting power lines, small animals, or even vehicles crashing into utility poles. High winds and storms increase the likelihood of such outages. Occasionally, a local utility will plan an outage to do repairs or upgrades to its electric distribution infrastructure. Consumers generally receive prior notice for a planned outage.