PJM has allowed a Maximum Generation Alert and Load Management Alert issued for the entire region it serves to expire effective 7:30 p.m. on Aug. 27. A Hot Weather Alert remains in effect for PJM through Aug. 28.
PJM issued the Maximum Generation Alert as a precaution due to a high load forecast and an increased amount of electricity being exported to neighboring regions. The alert is a procedural step PJM must take in order for PJM to have the flexibility to reduce exports should that be needed to maintain PJM’s reserve requirements.
PJM served a preliminary peak load of 146,530 MW on Aug. 27. As of 7:30 a.m. on Aug. 28, PJM expects to serve a forecasted peak of approximately 152,000 MW on Aug. 28.
The highest preliminary peak load that PJM has served so far this summer was approximately 153,400 MW and occurred on July 16. PJM’s all-time, one-day highest power use was recorded in the summer of 2006 at 165,563 MW. One megawatt can power about 800 homes.
Aug. 26 Update: PJM Issues Maximum Generation Alert for Aug. 27
PJM has issued a Maximum Generation Alert and Load Management Alert for Aug. 27 ahead of expected hot weather across many parts of the Eastern Interconnection, including the region PJM serves, to ensure the reliable delivery of electricity to its customers across 13 states and the District of Columbia.
PJM is issuing the alert as a precautionary measure after all PJM resources are committed and exports of electricity outside of the PJM footprint may need to be curtailed in order to maintain reserve requirements. No customer actions are required.
PJM issues a Maximum Generation Alert a day in advance of conditions that may require all generators to operate at their maximum output capability, and that the use of additional emergency procedures may be implemented. This alert is targeted at transmission and generation owners, who then determine if any maintenance or testing on any equipment can be deferred or canceled, in order to maintain the availability of all resources. PJM issues this alert at the same time as a Load Management Alert, which provides advance notice that demand response resources may be used.
PJM issues a NERC EEA Level 1, or EEA-1, in conjunction with a Maximum Generation Alert. NERC defines an EEA-1 as when a grid operator foresees or is experiencing conditions where all available resources are committed to meet electricity load, firm transactions, and reserve commitments, and is concerned about sustaining its required contingency reserves.
Read more about PJM’s emergency procedures and messages (PDF).
Original Story (Aug. 26): PJM Issues RTO-Wide Hot Weather Alert for Aug. 27–28
PJM has issued a Hot Weather Alert for Aug. 27–28 for its entire footprint in anticipation of hot and humid weather expected across the region.
A Hot Weather Alert helps to prepare transmission and generation personnel and facilities for extreme heat and/or humidity that may cause capacity problems on the grid. Temperatures are expected to go above 90 degrees across the footprint, which drives up the demand for electricity.
PJM is expecting to serve a forecasted load across the RTO of approximately:
- 149,100 MW on Aug. 27
- 151,300 MW on Aug. 28
The highest preliminary peak load that PJM has served so far this summer was approximately 153,400 MW and occurred on July 16. PJM’s all-time, one-day highest power use was recorded in the summer of 2006 at 165,563 MW. One megawatt can power about 800 homes.
Preparing for Hot Weather
PJM is prepared to serve the forecasted summer peak demand for electricity with approximately 185,000 MW of installed generating capacity available to meet customer needs. This includes sufficient resources available in reserve to cover generation that is unexpectedly unavailable or for other unanticipated changes in demand.
Last year’s peak demand was approximately 149,000 MW.
In preparation for summer, PJM has worked with transmission and generation owners throughout the spring to ensure that critical maintenance and system improvements were completed. To stay ahead of any fuel-related supply chain concerns, PJM continues to conduct fuel inventories every two weeks and monitors results for the generation fleet.
A dedicated team of operators uses sophisticated technology to balance supply and demand and direct the power grid 24/7 from PJM’s control rooms. They prepare multiple potential scenarios that could be impacted by weather, emergency conditions or equipment failure. They adjust resource output with changes in demand and ensure that no transmission lines or facilities are overloaded. The team also watches for unusual conditions and reacts to them to protect the electricity supply.
Read more about how PJM forecasts electricity demand on the PJM Learning Center.