Blackout trail leads to Ohio
Power company says alarm failed to signal early problems
(CNN) -- Three transmission lines in Ohio apparently started a chain reaction that caused the widespread blackout across parts of the Northeast, Midwest and southern Canada, according to utility officials.
But the investigation continues into why a few failed power lines led to such an extensive power outage, investigators said Saturday.
"So many asked, 'How could this happen?' We're asking that, too," said Michehl R. Gent, head of the North American Electric Reliability Council, an energy oversight organization.
FirstEnergy, a power company that provides electricity to 1.4 million customers in Ohio, said in a statement Saturday that some of its lines failed before the blackout and that an alarm system did not signal a problem. (Timeline of power line failures)
According to the statement, Unit 5 of the Eastlake Plant tripped hours before the blackout.
Later that afternoon, three more FirstEnergy transmission lines and one owned by American Electric Power and FirstEnergy tripped out of service.
"The Midwest Independent System Operator (MISO), which oversees the regional transmission grid, indicated that there were a number of other transmission line trips in the region outside of FirstEnergy's system," according to the company's statement.
FirstEnergy spokesman Todd Schneider said the company's computerized system for monitoring and controlling its transmission and generation system was working properly, but an alarm system to catch problems in the system was not.
MISO has told FirstEnergy that its system was functioning properly but did not catch any problems, Schneider said.
"Indications to FirstEnergy were that the company's system was stable, and FirstEnergy customers experienced no service interruptions resulting from these conditions," he said. "Therefore, no isolation of FirstEnergy's system was called for."
"These are very complex issues that will take time to analyze and work through," FirstEnergy Chairman and Chief Executive H. Peter Burg said in the statement.
In investigating the origin of the blackout, MISO is focusing on the four facilities in northern Ohio that experienced problems, MISO spokeswoman Mary Lynn Webster said.
Both Webster and Schneider said their companies are working with NERC to determine what led to the outage and to prevent another one.
"It's a big system and it's a big investigation," Schneider told CNN. He said the company will cooperate with any investigation, and added that FirstEnergy is conducting one of its own.
Power has been restored to almost all affected areas, but rolling blackouts continue sporadically across the region as power generators come online. The Midwest and Canada still have small, isolated outages and are especially vulnerable to continuing blackouts, officials said. (At a glance: Areas affected)
Gent said he was "fairly certain at this time that the disturbance started in Ohio."
He added, though, that the system should have prevented the cascading effect.
"It should have stopped, we think," Gent said. (Flash animation: Power grids explained)
U.S. Energy Secretary Spencer Abraham said his department's investigation will continue.
"We've got to quickly get to the bottom of the question of what happened, how it spread, and what we need to do to make sure it doesn't happen again," he told reporters from Albany, New York.
"I take no responsibility more seriously than that. And it will have the highest possible priority in the Department of Energy, in the administration, the executive branch, and it will receive all of the emphasis it needs to be resolved as quickly as possible."
The blackout began spreading in the Northeast, the upper Midwest and parts of Canada just after 4:10 p.m. Thursday, taking down 21 power plants in the next three minutes, according to Genscape, which monitors power transmissions in the United States.
Outages were also reported in Detroit, Michigan; Cleveland, Ohio; Erie, Pennsylvania; Toronto, Ontario; Ottawa, Canada; Niagara Falls in New York and Ontario; and other cities in Connecticut, Vermont and New Jersey. (Map of affected areas)
The three power lines that failed first were on a circuit known as the Lake Erie loop.
Gent said the loop of transmission lines has "been a problem for years, and there have been all sorts of plans to make this a more reliable thing, with cables under the lake and such, but nothing has come to fruition."
Gent's organization, NERC, will soon appoint a "well-known" person to lead its investigation. The electrical industry created NERC in 1965 after 30 million people in seven states and two Canadian provinces lost power in what became known as "The Great Blackout." The council is charged with designing systems to prevent such outages.
More than 60 million customers in the United States and Canada were affected at the height of the blackout. Only three deaths were tied to the outages -- two in Ottawa and one in New York.
In Cleveland, electricity was working, but Mayor Jane Campbell warned residents to boil drinking water because sewage might have contaminated the city's water system.
Canada and the United States have formed a joint task force to investigate the cause of the blackout and how to prevent it from happening again. (Full story)
• The power outage has cost New York City over a half-billion dollars in lost revenue, according to preliminary estimates from the City Council. Chris Policano, a council spokesman, estimated losses of $500 million to $750 million in lost income; $35 million to $40 million in lost tax revenue; and $6.5 million in overtime costs to emergency crews and other city workers. (Gallery: Images from the blackout and day after)
• Speaking in California, President Bush called the blackout "a wake-up call," and said the nation's electrical grid must be updated to ensure such events do not recur. (Full story)
• The outage also shut down cellular telephone service in many areas. High demand caused busy signals for some users. Others lost service because there was no power to supply cell sites, which house the antennas that transmit calls. (Full story)