http://www.washingtonpost.com/ac2/wp-dyn/A42391-2001Aug21?language=printer

The Day The Area Dodged a Blackout

August Heat Made Power Pool Sweat

By Peter Behr, Washington Post Staff Writer

Wednesday, August 22, 2001; Page A08

Early this month, the Washington area and the rest of the mid-Atlantic region got uncomfortably close to a California-style power shortage.

In the midst of a week-long heat wave Aug. 9, Potomac Electric Power Co. cut power levels by 5 percent across its D.C. and Maryland territories. Customers didn't notice, but the voltage-reduction decision was a warning that power reserves were near bottom.

It wasn't Pepco's decision.

The order came instead from the PJM Interconnection in Norristown, Pa., west of Philadelphia. Formed by utilities in 1927 to swap power, PJM is the region's electric-power overseer, directing generation and transmission decisions in the District, Delaware, New Jersey, most of Maryland and parts of Virginia and Pennsylvania. The voltage reduction that day was imposed by PJM throughout its region.

PJM operates a kind of stock market for energy and transmission paths where power-plant operators offer their output at competing prices and distributors such as Pepco shop for deals. It approves the transmission of power from other states into, out of and through the region, and it is responsible for steering the region through power emergencies.

Although PJM is held up by some federal regulators as one model for future super-regional power-pooling operations and can call on large power reserves, it isn't an island of self-sufficiency.

During the August heat wave, PJM required as much as 5,000 megawatts of power an hour from generators outside the region to cover record power demands of more than 54,000 megawatts. By 1:30 p.m. Aug. 9, the region's readily available standby power reserves had dropped below safety limits, and transmission lines into PJM from the west were full, said Tom Bowe, PJM's dispatch manager.

Thanks to the voltage reduction, it would have been possible to bring in extra power from New England, if that had been needed, Bowe said. But if a major generator had suddenly gone down that afternoon, the next step could have been rotating blackouts, PJM had warned, and it was a nervous time around the interchange. "Had the region lost a couple of large units, everyone would have been in trouble," said Richard J. Kafka, Pepco's principal engineer. "That's how close we were."

© 2001 The Washington Post Company

-- Swissrose (cellier3@mindspring.com), August 22, 2001