FirstEnergy asks Ohio to save power

The Akron, Ohio-based utility warned it might order rolling blackouts in the Cleveland area, lasting up to two hours, if the generation shortage worsens.

FirstEnergy resorted to rolling outages a day after the blackout as it struggled to restore normal operations on its part of the power grid after Thursday's massive U.S.-Canada blackout.

An initial assessment of the cause of the blackout by an industry group focused on three power lines near Cleveland operated by FirstEnergy. But industry officials say multiple failures were likely involved in the blackout, the biggest in North American history.

Temperatures in the Cleveland area were expected to reach into the high 80s degrees Fahrenheit Wednesday, according to the AccuWeather forecast service, pushing up demand for power to run air conditioners.

FirstEnergy's 1,320 megawatt Perry nuclear power plant in Ohio was knocked off the grid in last week's blackout and is not expected to be back in service until early Thursday, according to the company.

The Perry plant can supply power for more than 1 million homes.

The utility's 925-megawatt Davis-Besse nuclear station in Ohio has been closed since early 2002 to replace a badly corroded cap on top of the reactor vessel.