COLUMBIA, S.C. (WSPA) – Power companies in South Carolina say they’re back to normal operations following the Christmas weekend.

A combination of below-freezing temperatures and what officials called ‘unprecedented demand’ led to some issues.

Utilities asked customers to voluntarily limit their energy usage beginning on Christmas Eve morning through most of the weekend. They also said they would institute rolling blackouts for limited times to help prevent extended outages system-wide.

At one point this weekend, there were about 500,000 Duke Energy customers in North and South Carolina without power. Ryan Mosier, a spokesperson for Duke Energy said, “The combination of temperatures that were lower than forecast, customer usage that was higher than projected, and limited options for additional capacity from outside of our service area due to extreme cold weather that impacted the eastern half of the United States created conditions that resulted in the need to conduct temporary outages.”

According to the company, Duke Energy customers impacted by the coordinated rolling outages had their power restored on Saturday by 6 p.m.

Mosier said the company will be evaluating this event, “We were not able to communicate as proactively as we normally do, given the dynamic nature of the situation and fast-moving events occurring in the early morning hours.”

This weekend, Dominion Energy asked South Carolina customers to conserve energy. In a media release sent out Saturday, the company said, “Customers in South Carolina are asked to reduce their energy use at least through Dec. 27 to help protect the stability of the electric system. As the company works to meet customers’ energy needs, Dominion Energy may implement a controlled load shed in its South Carolina service territory, which may result in brief outages.”

A spokesperson for Dominion Energy did not respond to our requests before the deadline on Tuesday.

State-owned utility Santee Cooper also implemented measures to protect their electric system. Manager of Corporate Communications Nicole Aiello said, “We had unprecedented customer demand because of statewide arctic weather and we really had to be smart to make sure the grid was stable.”

Aiello said Santee Cooper had to do one rolling outage that lasted about 15 minutes. Officials say it impacted about 12,000 customers.

According to Aiello, due to the widespread impact of the event, they were not able to boost capacity like they normally would when demand increases. She said, “We always have the plan to have purchase power ready but the whole state was in the same situation as our neighboring utilities.”

Aiello said customers curtailing energy usage helped provide some relief during the event.