Pennsylvania Power & Light Co., along with 10 other member utilities of a regional power pool, reduced voltage on its electricity supply network Monday (5/20) to protect power reserves while continuing to supply emergency power to utilities in New York State.

A voltage reduction has few noticeable, and no lasting, effects on the operation of electrical devices. It slightly reduces energy consumption by appliances without affecting their operation. It will not damage electrical equipment.

The Pennsylvania-New Jersey-Maryland Interconnection called for the voltage reduction shortly after 3 p.m. at the request of the power pool that serves New York State utilities. The unseasonably hot weather has increased demand for electricity throughout the Northeast.

"PP&L, as a member of the PJM power pool, joined this temporary action to quickly reduce demand on the power supply system," said John F. Sipics, PP&L's general manager for Power Systems Support. "Reducing voltage helps assure continued service to customers."

Voltage is the amount of "pressure" sending electrical current along a power line. Reducing voltage is like cutting down the pressure of water flowing through a garden hose.

Customer demand within PP&L's service area and throughout the PJM power pool region did not approach summer record levels Monday. The voltage reduction was needed, however, because available power supply in the Northeast is lower than it would be on a typical hot summer day.

Utilities schedule much of their power plant maintenance in the spring, when demand for electricity generally is low. PP&L has two large fossil-fuel generating units out of service for scheduled maintenance.

Sipics said PP&L is not asking customers to curtail their use of electricity, but to use energy wisely during this hot spell. One way customers can help is by shifting the use of major electric appliances, such as washing machines, clothes dryers, dishwashers and electric stoves, to early morning or late evening hours.

"We will continue to update the public and our customers on the status of regional power supplies," Sipics said.

PP&L supplies electricity to about 1.2 million customers in Central Eastern Pennsylvania.

The 11 member utilities of the PJM serve more than 22 million customers in a 50,000-square-mile area in Pennsylvania, New Jersey, Maryland, Delaware, Virginia and Washington, D.C.