Duke Energy officials say several factors caused the utility company to implement rolling blackouts on Christmas Eve for the first time in its history. Severe cold weather caused very high demand and not enough supply.
Duke Energy lost about 1,300 megawatts of power when three of its plants had to reduce generation because some equipment froze, despite weatherization efforts.
Duke tried to increase its supply of electricity by purchasing power from other utilities, but those companies were having similar problems, so that power never came through.
Duke Energy representatives apologized to customers at a public briefing in front of the North Carolina Utilities Commission. Company executive Sam Holman says the outages were necessary to avoid losing control of the entire system.
"Our operators were faced with very difficult operating conditions and very difficult decisions,” he said. “We understand the gravity and the significance these decisions had on our customers."
Duke Energy says it is promising to learn from this event. Officials say they are working to improve its equipment for the future.
About 500,000 customers in North and South Carolina were affected.