American Electric Power: Hero or Zero?By Mel Duvall | Posted 2003-11-01 Email Print
The Ohio utility's systems protected its 4.9 million customers during the Aug. 14 blackout. But did they knock out power to 50 million people in the process?
Investigators are sifting through clues from a brush fire in southwestern Ohio, a tree branch that should have been trimmed, and three separate power-plant failures on the afternoon of Aug. 14, in their attempts to find the root cause of North America's largest blackout.
In the end, investigators from the power industry's North American Electric Reliability Council and a U.S. House Energy and Commerce committee may not be able to pin the outage on any single event. Damage is pegged at somewhere north of $4 billion for the eight states and one Canadian province involved. Power providers, transmission-grid operators and even energy regulators all have suffered black eyes for the failure.
Yet one Midwest utility came off looking a little smarter than its peers. Perhaps even a little smug.
American Electric Power (AEP) of Columbus, Ohio, one of the largest electric utilities in the country, managed to isolate itself from the cascading blackout that may have been triggered by, among other things, the untrimmed tree branch in a neighboring utility's service area.
Only 14,000 of AEP's 4.9 million customers were affected by the blackout. The vast majority of the utility's transmission lines, power plants and other equipment was unscathed.
The reason? The company's computer systems, controls and relays operated the way they were meant to, says chairman and chief executive E. Linn Draper. "The AEP system held togethera point of pride for us," he says. "Our protective systems performed automaticallyas they were designed to perform."
At the heart of AEP's response were a small army of relaysdevices designed to trip or cut off power in the event of a sudden surge of electricity or load imbalances. AEP won't release details about its computer systems or relays, citing concerns for national security. But the company has been one of the more-aggressive utilities in deploying a newer generation of microprocessor-based relays. Since the early 1990s, the company has been gradually replacing its older electromechanical relays, installing the digital relays in new and upgraded plants.
Those digital relays are largely being credited with detecting extreme demands for power emanating from FirstEnergy Corp.'s lines in northern Ohio on Aug. 14. The relays slammed AEP's transmission lines shut in milliseconds, preventing AEP's power plants from being knocked out or damaged.
If AEP hadn't been able to isolate itself from the runaway electricity freight train, Draper says it was entirely possible the blackout could have spread "across the AEP system and probably far beyond'' the areas that got affected in the nation's worst power outage to date. Had AEP not been able to shut its lines down, the blackout could have spread to the Southeast and possibly the Southwest. AEP has a sizeable operation in Texas.