KANSAS CITY, Mo. — For the second day in a row, Kansas Citians have faced rolling power outages as extreme temperatures across the Midwest have stressed the regional power grid.
On Tuesday morning, Evergy, which provides power to more than 1,700,000 customers across Kansas City, said as many as 25% of its customers could face temporary rolling blackouts Tuesday as demand for electricity outstripped supply.
"The very reason that we are doing these temporary emergency power outages is to avoid something like what is occurring in Texas right now, where there are millions of people out for 6 or 7 hours, some more than a 24-hour period," Chuck Caisley, senior vice president of marketing and public affairs at Evergy, said.
In the Lone Star State, demand overwhelmed the power grid, causing it to fail.
But Evergy says there’s enough power locally, so why the need for temporary outages here?
The easiest one to understand is that it’s cold and has been cold for more than a week, and that it’s been cold for more than a week for a large part of the country. People demand more power when it’s cold.
Another factor relating to the cold: The machines that generate power become less efficient when it’s cold, reducing the generation capacity.
Compared to Monday, which was a national holiday, Tuesday featured a return to more normal operations, which further increased electrical demand.
During a news conference Tuesday morning, Caisley also cited power plants going offline in Iowa and Oklahoma as reducing the overall capacity of the grid to generate power.
Another factor: by the very nature of having a regional grid, excess power in one part of the region can be sent to a part of the grid that doesn’t have enough. But transmitting that power over long-distance power lines creates congestion in the same way rush hour can block up a highway.
Caisley says the grid has been attempting to send power generated in the northern part of the region to the southern part, and the power has been congested on transmission lines in the middle of the grid, which includes Evergy’s service territory.
He likened the grid to a plate balancing on a pencil. If demand builds up on one side and there's not enough supply, then the whole thing can be destabilized. That is when large-scale, prolonged blackouts occur.
"In a system that big, if there's a problem one place, it could be a problem that impacts us everywhere," Caisley said.
According to the Southwest Power Pool, Monday’s peak demand of roughly 43.7 gigawatts could be eclipsed today, when officials predicted a peak demand of 44.6 gigawatts Tuesday morning.