Heat boosts US Mid-Atlantic power demand; prices remain moderate

New York — As stifling heat and humidity continued to broil the US Atlantic Coast, the PJM Interconnection issued Hot Weather Alerts through July 22, although real-time power prices remained at moderate levels as the afternoon of July 20 progressed. Loads were also forecast to ramp up across the footprints of the other east coast grid operators.

"PJM has issued additional Hot Weather Alerts for its Mid-Atlantic region and Dominion [zone] for July 21 and 22 amid continued hot weather along the Atlantic Coast," the grid operator said on its website.

The alerts are in effect from 7 am to 10 pm ET July 20-22. PJM had previously issued alerts for July 18–20 for its entire footprint.

The Mid-Atlantic region includes the Atlantic City Electric, Baltimore Gas & Electric, Delmarva Power, Jersey Central Power & Light, Met-Ed, Penelec, PECO, PEPCO, PPL Electric Utilities, PSE&G and Orange & Rockland: Rockland Electric Company transmission zones, PJM said.

PJM transmission and generation dispatchers are asked to review plans to determine if any maintenance or testing, scheduled or being performed, on any monitoring, control, transmission or generating equipment can be deferred or canceled.

Power demand peaked over the weekend at 138.755 GW between 5 to 6 pm ET on July 18 and 136.363 GW between 5 to 6 pm ET on July 19.

So far in July, peakload has averaged 130.719 GW, steady with year-ago levels. PJM's all-time peakload record is currently 165.492 GW, which was set in July 2011.

"Hot Weather Alerts are issued when temperatures are expected to exceed 90 degrees Fahrenheit with high humidity, driving up demand for electricity. High temperatures are expected to remain in the 90s with higher heat indexes anticipated," PJM said.

The PJM Western Hub real-time price was $31.96/MWh at about 3 pm ET on July 20 and the highest real-time price was $76.25/MWh in the Penelec zone, according to PJM's website.

The PJM Western Hub on-peak day-ahead price has averaged about $30/MWh so far this month, about 5% lower than during the same period last year.

NYISO, ISO-NE

The New York Independent System Operator forecast power demand in its footprint would reach nearly 30 GW on July 20 and the grid operator had activated Special Case Resources and Emergency Demand Response Program Resources in the Targeted Demand Response Program starting at 4 pm ET and ending at 10 pm ET, according to the NYISO website.

Temperatures were over 90 degrees Fahrenheit around 3 pm ET, with nearly 80% humidity in the Hudson Valley region.

NYISO forecasts that peakload this summer will reach 32.296 GW, which is a decrease of 86 MW from the 2019 baseline forecast and 1.3% above the 10-year average peak of 31.867 GW, the grid operator said in its summer preparedness outlook.

Peak demand in summer 2019 of 30.391 GW was recorded on July 20, while New York's record peak of 33.956 GW was reached in July 2013 at the end of a week-long heat wave.

Real-time power prices averaged in the low- to mid-$20/MWh range in the late afternoon, with slightly higher prices in Long Island Zone K of $59.91/MWh, according to the NYISO website.

ISO New England reported normal power system conditions as of the late afternoon. Power demand was forecast to peak at 24.5 GW on July 20 and 22.21 GW on July 21, according to the ISO-NE website.

Under normal weather conditions, peak demand for summer 2020 is forecast to be 25.13 GW and could hit 27.1 GW under extreme weather conditions, according to the grid operator's summer outlook.

The summer 2019 peak of 24 GW was set on July 30 and ISO-NE's all-time highest summer peak demand of 28.130 GW was set on August 2, 2006.

Real-time power prices across the ISO-NE footprint averaged $29.19/MWh during late July 20 afternoon.