Chicago Midway Airport

Chicago, IL

Passengers in a terminal, Chicago Midway Airport.


Grumman Butkus Associates was retained to provide retro-commissioning services for Chicago Midway Airport. Areas included the terminal building and concourses (approximately 938,000 square feet). The project was part of the University of Illinois Smart Energy Design Assistance Center (SEDAC) program, which requires a minimum implementation of $10,000 of energy efficiency measures within one year of RCx.


During the planning phase, GBA performed detailed investigation and functional performance testing of 59 air-handling units. Identified savings measures included the following:

  • Removing inlet guide vanes (IGVs)
  • Installing variable fan drives (VFDs)
  • Equipment operation scheduling
  • Supply air temperature (SAT) reset
  • Static pressure relief

Identified savings include the following:

  • 4,058,526 kWh in potential electric savings were identified, which is the equivalent of $267,886 savings annually
  • 320,333 therms in potential natural gas savings were identified, which is the equivalent of $185,796 savings annually

The identified energy savings represent a total facility cost savings opportunity of 8%, for an estimated simple payback of 1.59 years.

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