By Christen Smith
PJM’s grid coasted through an “uneventful” summer highlighted by a new record for weekend peak load and the lowest forced outrage rate in five years — the result of evolving resources and system planning, the RTO said in a report published Wednesday.
“The system would not have handled these high demands as smoothly a decade ago,” said Kevin Hatch, a supervisor in PJM’s dispatch system operations. “We are seeing generators that are increasingly responsive to our operational requests, a transmission system that is more robust, and the benefits of efficient and reliable resources through the capacity market.”
Summer demand peaked at 151,558 MW on July 19 in the midst of a hot weather alert — one of 13 called in the region during the season, which spanned June 1 through Sept. 15. The following day, the grid set a new weekend peak load record of 149,751 MW. The average LMP hovered around $25/MWh, with prices during the daily peak spiking to $45/MWh.
Although “relatively” mild weather enhanced the grid’s smooth performance, the report emphasizes the “excellent coordination and cooperation” of PJM members, including responsiveness to dispatch operations, system upgrades and the influx of more efficient generators via the capacity market. These newer resources have replaced aging equipment, driving forced outage rates below 3% this summer, the RTO said.
“We appreciate the cooperation and coordination with our member utility companies,” said Mike Bryson, PJM’s senior vice president of operations. “More efficient generators mean fewer outages, greater reliability and a more efficient system overall.”
The report also credited lower fuel prices — combined with the season’s hottest temperatures occurring during periods of lower demand — for keeping LMPs down. Average daily gas and coal prices were 64 cents/MMBtu and 31 cents/MMBtu cheaper, respectively, compared to 2018.
No capacity emergency procedures occurred during the summer. PJM reported three spinning events and 13 hot weather alerts, the fewest recorded in a summer season since 2014. The grid experienced less than 80 post-contingency local load relief warnings, another five-year record low.
Two “notable” gas pipeline events caused temporary disturbances in PJM, according to the report. On Aug. 1, a 30-inch segment of the interstate Texas Eastern Transmission Pipeline in central Kentucky exploded, just a few miles south of a gas-fired generator that serves PJM. The explosion did not harm the unit, and operators isolated the damaged section, saving the grid’s supply of shale gas that flows through the region.
Six weeks later, a compressor station in Northern Virginia on the Dominion Energy Transmission pipeline failed during scheduled maintenance. PJM said a “spell of later summer heat” and the typical generator outage season meant that certain units downstream of the station lost gas supply temporarily. No emergency procedures were issued.
Shoulder Season Surprise
An unexpected hot weather alert on Oct. 2 forced PJM to call upon demand response resources to effectively manage the 126,000 MW peak load.
The RTO declared a pre-emergency load management reduction action just before noon in the American Electric Power, Baltimore Gas and Electric, Dominion and Pepco zones. This directive triggered a performance assessment interval — which measures the production of all resources with Capacity Performance commitments in the affected zones — that lasted approximately two hours.
“We count on our utility partners, generation resources and load management to perform during these tough days, and they did just that,” Rebecca Carroll, PJM’s director of dispatch, said in a statement last week.
Although the event occurred outside the summer season, PJM will address both the report and the DR event at its Operating Committee meeting Tuesday.