PA Environment Digest Blog: PJM Interconnection Maximum Generation Alert Remains In Effect For Sept. 18; Emergency Demand Response Customers Activated On Sept. 17 To Increase Reserve Generation Because More Generation Went Offline

On September 17, the PJM Interconnection announced it activated Emergency Demand Response customers in several areas of its service territory on Thursday to increase generation reserves to meet evening power demands.

While PJM attempted to recall or cancel transmission and generation maintenance outages yesterday, 36,000 MW of generation remains offline-- 1,000 MW more than PJM reported Thursday.

PJM said forecast peak usage on September 17 was 133,468 MW and it had 141,606 MW of capacity available-- an 8,138 MW difference.

PJM also noted it received a combined emergency order, to be effective through Sept. 18, from the U.S. Department of Energy. The order gives PJM operators additional flexibility to respond to changing system conditions by:

-- Providing temporary relief from environmental permit restrictions for generating units

-- Authorizing PJM to direct data centers and other large load customers to switch to backup generation resources, if necessary.

Alerts Remain In Effect

A Maximum Generation / Load Management Alert remains in effect for the PJM region for September 18.

Above-normal temperatures are forecast across much of the PJM footprint, with load expected to peak at approximately 132,000 MW (forecast as of noon, Sept. 17).

The higher temperatures are driving higher electricity demand in PJM while also increasing the need for exports to neighboring systems to the south and west, where the weather is even hotter.

9th Hot Weather Event

This is the ninth Hot Weather Alert of the summer. The others were issued for May 18-20, June 5-6, June 11-12, June 18, June 29 to July 5, July 14 to 17, August 9 to 11, and August 31 to September 4.

Click Here for the PJM announcement.

The PJM Interconnection coordinates the wholesale electricity grid and markets for all or parts of 13 states—Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia—plus the District of Columbia.

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