Dive Brief:

• A power outage at Atlanta's Hartfield-Jackson International Airport led to the cancellation of more than 1,000 flights and passengers being stuck in planes and at terminals for hours. 
• The 11-hour outage at the world's busiest airport was caused by a fire at an underground electrical facility owned by Georgia Power, the company said in a news release. Power was restored to the airport around midnight on Sunday. 
• The outage triggered criticism for Georgia Power on social media, with observers, including a former U.S. Transportation Secretary, questioning why a backup power source was not activated for the airport.  

Dive Insight:

With millions of travelers gearing up for the winter holiday rush, the world's busiest airport was plunged into darkness on Sunday, stranding hundreds of passengers in landed planes and disrupting travel across the United States. 

A fire at a Georgia Power underground facility resulted in 1,180 flights canceled at the airport, a frequent layover point for flights connecting across the country. More than 400 flights are reportedly canceled on Monday as well.

The fire began after 12:30 p.m. on Sunday in one of the underground tunnels that houses the airport's electric system, Georgia Power officials said on Sunday. The fire resulted in a full outage at the airport shortly after 1 p.m.

The outage sparked criticism from many travelers on social media, including former Transportation Secretary Anthony Foxx, who questioned why a backup power system was not deployed:

Total and abject failure here at ATL Airport today. I am stuck on @delta flight, passengers and crew tolerating it. But there is no excuse for lack of workable redundant power source. NONE! #atlairport #delta

— anthonyfoxx (@anthonyfoxx) December 17, 2017

The airport does, in fact, have a backup power system, but the utility said the underground fire damaged equipment that could trigger its activation. 

"[A] piece of Georgia Power switchgear located in the underground electrical facility could have failed and started a fire," the company said in a statement. "This fire was located adjacent to redundant circuit cables and switching mechanisms serving the airport and those cables were damaged, resulting in the outage and loss of redundant service methods."

The airport outage comes amid an enhanced focus on power sector resilience from federal and state officials across the country. This fall, the Department of Energy proposed a controversial power market rule that would subsidize coal and nuclear plants with extended fuel supplies. It is currently under consideration at the Federal Energy Regulatory Commission.

Many energy analysts say the plan would do little to enhance the resilience of the power system, as the vast majority of outages result from issues with transmission and distribution grid infrastructure, not the fuel supplies of plants. They argue more durable grid infrastructure and the use of more distributed generation resources and microgrids would do more to help the grid bounce back from outages. 

The outage is another black eye for Southern Co., the parent company of Georgia Power and owner of utilities across the South. Earlier this year, the company abandoned work on a high-profile clean coal project, and Georgia regulators will meet this week to decide whether the utility can finish work on a long-delayed nuclear project. 

The utility said it is still working to determine the cause of the airport fire, which also damaged substations serving the airport.