ALBANY, N.Y. — NYISO performed an autopsy on the system conditions during the late June heat wave for the New York State Reliability Council at its Installed Capacity Subcommittee meeting on July 10. 

“We got a net demand on the 24th of 31,857 MW, which is over our 50/50 forecast by a couple hundred megawatts,” said Aaron Markham, vice president of operations for NYISO. “When we add back in the assumed behind-the-meter [solar], we were pretty close to the 34,000 MW load we hit in 2013.” (See NYISO Issues Energy Warning as Heat Wave Boils N.Y.) 

By 3 p.m., Markham said, neighboring reliability coordinators reduced imports to New York by about 730 MW, increasing to 1 GW by 5 p.m. NYISO cut exports in response, to a total of 1,660 MW by 5 p.m. 

Between 5 and 6 p.m., the Astoria 3 generator tripped and NYISO declared an Energy Alert. The ISO escalated the alert to an Energy Emergency at 7:13 p.m. as more imports were cut. As the evening wore on, NYISO purchased emergency energy to meet 30-minute operating requirements several times. 

In total, about 2,000 MW of power were curtailed from NYISO from neighboring areas. New York generators tripped or otherwise experienced performance issues, resulting in about 1,000 MW of derates during peak hours. 

“The driver was really high demand that stressed system conditions regionwide due to the heat and performance issues,” Markham said. 

NYISO called on all the demand response programs and saw about 1,000 MW of relief. It also dispatched generation to optimize 30-minute reserves. The ISO purchased about 1,960 MW across all available interfaces. 

Markham said all fuel types were needed during the event but that it looked like wind and solar did better than NYISO initially assumed they would in its summer capacity assessment.