Although it's not as hot as it was during the recent, record-setting heat wave, electricity supply across the five-state, regional power pool could be tight this week because several large power plants in New Jersey and Maryland are out of service.

The Pennsylvania-New Jersey-Maryland Interconnection, the 11-utility power pool that includes Pennsylvania Power & Light Co., expects electricity use to be at near-record levels by the middle of the week if the hot humid weather continues.

During the recent heat wave on July 14, customers of the power pool set a new all-time record, using 47 million kilowatt-hours of electricity. That day PP&L customers used 5,779,000 kwh of electricity, setting a new summertime mark. PP&L's all-time record is 6,508,000 kwh, set Feb. 6, 1995.

"Because reserve margins are low, an unexpected loss of additional generation could lead to a tight supply situation that would require the power pool to instruct utilities to ask their customers to conserve electricity," Barry Trayers, PP&L's manager of bulk power system operations, said Monday (7/24). "That's not the situation yet, but as always we ask customers to use energy wisely and to put their own health and safety before any other concern. We will keep the public informed as the situation progresses."

All PP&L power plants are operating, except one generating unit at the Martins Creek power plant, which is out-of-service because of equipment problems.

PP&L supplies power to about 1.2 million customers in Central Eastern Pennsylvania. PJM coordinates the distribution of power for more than 22 million customers in Pennsylvania, New Jersey, Maryland, Virginia and Washington, D.C.