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For Immediate Release


Pepco and PJM Power Pool Utilities Reduce Voltage 5 Percent;

Pepco Makes An Emergency Electric Power Appeal

For Immediate Release
August 9, 2001

Because of heavy demand for electricity in the mid-Atlantic region, Pepco and the other members of the regional PJM Power Pool reduced system voltage by 5 percent at about 3:15 p.m. today. These companies operate as a single system to provide electric service to more than 22 million people in the mid-Atlantic area.

Pepco and the other power pool companies also urgently request that customers cut back virtually all their non-essential electricity use, including air conditioners, unless it is equipment required for health or safety purposes. PJM companies request this action to avoid the initiation of rolling black-outs, which may otherwise be necessary to prevent the complete failure of the electric power grid. THIS IS A VERY SERIOUS SITUATION.

Today`s energy emergency is due to extremely hot weather and high customer demand that is challenging the PJM companies' ability to deliver electricity. Pepco also has asked selected large commercial customers to reduce their consumption; these customers have agreed in advance to reduce their load, at Pepco's request, during times of tight supply.

A voltage reduction reduces demand because equipment and appliances will use less power to function. The voltage reduction will not be noticeable to the vast majority of customers, because most computers, motorized equipment and appliances can generally operate satisfactorily at lower voltages. Once operating conditions on the PJM system return to normal, the voltage reduction will be lifted.

The PJM pool serves all or parts of Pennsylvania, New Jersey, Delaware, Maryland, Virginia and the District of Columbia.

NOTE: A volt is a unit of electrical pressure that pushes electrons along a conductor. This is similar to the pressure that pushes water through a pipe. Most motors and other appliances are designed to tolerate a voltage variation of plus or minus 10 percent.

Point of Contact:
Makini Street

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