New York’s recent peak day for electricity consumption came during a heatwave, as millions of people relied on their air conditioners to keep cool. That’s not unusual. However, some of the circumstances leading up to that day still provided a challenge.

On our latest Power Trends podcast, NYISO’s Vice President of Operations Aaron Markham discusses what goes into maintaining a reliable grid during a late-season heatwave. 

The peak load on Sept. 6 was just over 30,200 megawatts. New York’s historic peak demand is 33,956 megawatts, recorded in July 2013.

Markham pointed out that there have been several system changes since then, like generator retirements.  

It’s unusual to see a peak day in September. The high-demand days usually come in July or August when hot, humid conditions drive up the desire for air conditioning. Besides the peak coming later in the season than expected, there were other unusual factors that came up.

“We had some generation that became forced out of service,” Markham said.

When something like that happens, the operators in the control room activate contingency plans.

“That resulted in us committing some additional generation to make sure we had sufficient supply,” he explained.

On a peak day like this, very close coordination with utility companies is also essential.

“The expectation is that we've talked through all the potential contingencies that could occur,” Markham said. “What is a system going to look like? What is the set of resources that we're going to use to resolve that and make sure that everybody is on board, from the neighbors to the utilities in the state, to the NYISO operators in the room.”

Challenging situations aren’t limited to warmer months. Markham’s team of operators had to deal with a different set of conditions brought on by sudden extreme cold in December 2022.  

With high demand for natural gas to heat people’s homes, meant less gas available for generating electricity.

“We have a survey process where we actually reach out to the generators to look at…what is their fuel supply situation? Do they have alternate oil backup in the tanks? Are they expecting deliveries of that?” Markham explained. “So that's another aspect that comes into winter operations, all of which we did leading up to this event.”

Events like this demonstrate New York’s system is reliable, Markham said.

“We were able to maintain flows within limits, all the various parameters on the power system within limits. And we still did have, through the event, some surplus capability,” he said.

To learn more about our Operations Team and how they manage the grid, listen to the podcast.

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