The Tennessee Valley Authority is reviewing why it had to institute rolling blackouts in north Alabama on Christmas Eve to conserve energy as the area experienced below-freezing temperatures.

More than 1,100 residents around Huntsville were without power for a large duration of the mandatory rolling blackouts while much of north Alabama’s electricity was cut intermittently in intervals of roughly 30 minutes.

“We at TVA take full responsibility for the impact we had on our customers. We never want to impact anyone’s energy at any time. This is not the way we want to serve our communities and customers,” the TVA said in a statement Wednesday announcing the review.

“We are conducting a thorough review of what occurred and why,” the authority’s statement continued. “We are committed to sharing these lessons learned and – more importantly – the corrective actions we take in the weeks ahead to ensure we are prepared to manage significant events in the future.”

During a 24-hour period on Friday, the agency said, it “supplied more power than at any other time in its nearly 90-year history. This event also produced the highest winter power peak in TVA history.”

The rolling blackouts marked the first time TVA had to take the measure “due to extreme power demand,” the authority said.

“We will learn from this unprecedented event and are committed to providing you with the reliable service you expect and deserve,” the TVA statement concluded.