While power is back on at the Atlanta Hartsfield-Jackson airport, the question remains: what happened to make the busiest airport in the world lose power for 11 hours on Sunday and strand tens of thousands of passengers for days?[1]

 

Basically, an electrical fire in a tunnel beneath the airport crippled the main power system and its backup.[2]

 

How did the fire start?

 

Atlanta Fire Rescue Department in partnership with Atlanta Police Department, the Bureau of Alcohol, Tobacco and Firearms and the FBI Joint Terrorism Task Force stated that the fire was caused by an electrical failure in a tunnel under the airport.[3] They explained that insulation and other combustibles inside, what is basically, a massive circuit breaker known as a “switchgear box” were ignited by an intense arc flash.[4]

 

An “arc flash” is a sudden burst of heat and light that occurs whenever an electrically conductive object, say, a piece of metal, gets too close to an exposed current source.[5] Arc flashes can happen because of accidental contact, underrated equipment, contamination or tracking of insulated surfaces, and deterioration or corrosion of equipment.[6]

 

How did the fire cut power?

 

Essentially, when the airport’s switchgear ignited beneath the tunnel that housed electric cables, it burned a wall through which the cables travel, damaging the cables, and in the process, disabling both the main and the redundant electric systems.[7]

 

“Redundant systems” are backups components that are intended to increase the reliability of the system by establishing a fail-safe.[8] Often times however, because of the great reliability of modern electrical and mechanical components, redundancy is unnecessary.[9] But if the cost of failure is high enough, say, at the world’s busiest airport, then a redundant system is an attractive option.[10]

 

Why did the outage last so long?

 

The fumes that resulted from the fire in the tunnel prohibited the Georgia Power response team from gaining access, slowing the repair by several hours and allowing the power outage to extend for nearly half a day.[11]

 

Will this happen again?

 

The investigation into exactly what happened and why will continue through the rest of the week.[12] In the meantime, Georgia Power is exploring how to prevent this from happening again.[13] Ideas include encasing in concrete the area that holds vital electric equipment or moving parts of the system to other areas so that a small fire will not again debilitate a massive airport.[14]

 

The specifics of this case are unique, but they also highlight the need for a more resilient power system that accounts for the likelihood of occurrences like this. It is more than ironic that “redundant systems” were disabled, leaving them less redundant than was hoped for. As we discussed in “Building a Smarter Electric Grid: How Investing in Smarter Electricity Will Energize America,” a more intelligent grid can serve as a platform for the storage and exchange of energy from multiple sources allowing critical infrastructure, like an airport to get back up and running in far less than

 

 

 

Citations to more resources:

[1] Horowitz, Julia. “What Caused the Atlanta Airport Power Outage?” CNNMoney, Cable News Network, 18 Dec. 2017, money.cnn.com/2017/12/18/news/atlanta-hartsfield-jackson-power-outage-cause/index.html.

[2] Horowitz.

[3] Reed, Kristen. “Atlanta Airport: Claim That Rat Caused Power Outage ‘Crap’.” WXIA, 20 Dec. 2017, www.11alive.com/article/news/local/atlanta-airport-claim-that-rat-caused-power-outage-crap/85-500668684.

[4] “Electrical Switchgear Protection.” Electrical Switchgear Protection, www.electrical4u.com/electrical-switchgear-protection/; Reed.

[5] “What Is An Arc Flash.” Graphic Products Info, 13 Dec. 2017, www.graphicproducts.com/articles/what-is-an-arc-flash/.

[6] Clark, Cameron. The Basics of Arc Flash. www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=16&ved=0ahUKEwjOxY–mZnYAhXDTCYKHTN4DvMQFgh0MA8&url=https%3A%2F%2Fwww.geindustrial.com%2Fsites%2Fgeis%2Ffiles%2Fgallery%2FThe-Basics-of-Arc-Flash-Article_GE_Industrial_Solutions_0.pdf&usg=AOvVaw1pE_4p-q8bbTnwOz8AsUtc.

[7] McLaughlin, Eliott C., and Martin Savidge. “Thousands Trying to Get out of Atlanta after Lights Went out at Hartsfield Airport.” CNN, Cable News Network, 18 Dec. 2017, www.cnn.com/2017/12/18/us/atlanta-airport-power-outage/index.html; Horowitz.

[8] “Redundant System Basic Concepts.” Redundant System Basic Concepts – National Instruments, 11 Jan. 2008, www.ni.com/white-paper/6874/en/.

[9] Id.

[10] Id.

[11] Horowitz.

[12] Steinbuch, Yaron. “FBI Joins Probe into Power Outage at Atlanta Airport.” New York Post, New York Post, 19 Dec. 2017, nypost.com/2017/12/19/fbi-joins-probe-into-power-outage-at-atlanta-airport/.

[13] Steinbuch; Horowitz.

[14] Steinbuch.