Electricity Markets

Unusually hot start to fall pressures power grids

Against the backdrop of much hotter than normal temperatures for this time of year, power grid operators reported a resulting spike in power demand and new demand records.

The Weather Channel reported that daily record highs were set on several days during fall's first week in the South. “Now, that has been capped off by all-time record heat for the month of October,” it said in an Oct. 2 post on its website. “More than a dozen cities in the East, from upstate New York to the Florida Panhandle, set all-time October record highs on Tuesday.”

On Oct. 2, the Electric Reliability Council of Texas reported setting another new peak demand record for the month of October. Preliminary operating data showed peak reaching 65,066 MW between 4 and 5 p.m. This was nearly 400 MW more than the October record set Oct. 1. ERCOT market data shows day-ahead electricity prices exceeding $800 late in the afternoon of Oct. 2.


The PJM Interconnection, the grid operator for the Mid-Atlantic, reported that its members in generation, transmission and load management worked together successfully on Wednesday (Oct. 2) “to keep the power flowing during one of 2019’s most challenging days.”

“On a day that produced 90-degree temperatures across much of the Midwest, Mid-Atlantic and the South, member companies and their customers with interruptible service answered PJM’s call to reduce load on Wednesday. Their actions helped manage the afternoon load resulting from unseasonable customer demand,” PJM said.

The preliminary peak load of more than 126,000 MW would be the second highest October demand total for the PJM footprint on record, second to the 134,000 MW mark set in October 2007, and just over the approximately 125,000 MW demand registered on Tuesday (Oct. 1).

PJM declared a pre-emergency load management reduction action just before noon eastern in the AEP, Baltimore Gas and Electric, Dominion and Pepco zones. The purpose of this action was to provide additional load relief by using PJM controllable load management programs, such as voluntary commercial, industrial and residential programs in which customers receive compensation for agreeing to reduce their consumption during times of stress to the grid.

The action also triggers a Performance Assessment Interval, which measures the production of all resources that were committed to perform under PJM’s capacity performance rules.

PJM implemented capacity performance to ensure that energy is available when it is needed most, such as during severe hot and cold weather.

PJM noted that under capacity performance, resources that fail to meet their commitment during emergencies are assessed a penalty. Resources that exceed their obligation, and those that perform during an emergency despite having no capacity obligation, are entitled to receive some of the funds collected from underperforming units.

The grid operator noted that October falls within the power industry’s shoulder season between the highest-demand seasons of summer and winter, and is traditionally one of the prime months for scheduled maintenance for PJM’s transmission and generation owners.

Because a variety of generators typically are out of service for maintenance during this time, PJM issued an alert Tuesday afternoon – called Maximum Generation Emergency/Load Management Alert – to check on the availability of those generators in case they are needed.

PJM noted that Thursday was expected to be considerably cooler, and electric usage was expected to be much lower, as the region returns to more fall-like weather.


Meanwhile, the Tennessee Valley Authority reported that Monday's peak power demand was 28,141 MW at a system average temperature of 95 degrees.

TVA had nine days in September with demand over 28,000 MW, the most in TVA history.

Monday's peak power demand was 28,141 MW at a system average temperature of 95 degrees, the highest average peak load for any September in TVA history.