O’Hare’s $250m Midfield Cooling Plant Takes Shape as ORDNext Expansion Progresses

Construction is progressing on a major new infrastructure project at Chicago O’Hare International Airport, where work has begun on a $250 million Midfield Cooling Plant designed to support the airport’s expanding terminal facilities under the ORDNext programme.

Crews began pouring concrete for the plant on 13 October, followed by the installation of precast concrete walls the following week. The facility will provide centralised cooling for O’Hare’s new terminal developments, including The New Concourse D, The New Concourse E and, eventually, the O’Hare Global Terminal.

Scheduled for completion in 2028, the plant will operate as a large-scale central air-conditioning system, pumping chilled water through approximately 8,600 feet of piping to cool the new facilities. At peak capacity, the system will be capable of circulating more than 300,000 gallons of water.

The Chicago Department of Aviation (CDA) and its design and construction partners identified during the ORDNext planning process that O’Hare’s existing Heating and Refrigeration Plant, located near Terminal 3, would not have sufficient capacity to serve the airport’s expanded terminal complex. A new centralised facility is expected to reduce maintenance and energy costs, ease mechanical demands and free up space in the terminals for passenger amenities and operational facilities.

“The Midfield Cooling Plant is a critical investment in O’Hare’s future,” said Chicago Department of Aviation Commissioner Michael McMurray. “As we build new concourses and the O’Hare Global Terminal, we’re also building the infrastructure that will keep those facilities operating efficiently for decades to come.”

The cooling plant will use a hydronic system, chilling water before pumping it through cooling coils in air-handling units across the new terminal facilities. Water will travel distances of up to 2,500 feet at approximately 42°F, absorb heat as it passes through the air-conditioning systems, and return to the plant at around 55°F to be cooled again.

Four water-cooled centrifugal chillers will provide a combined cooling capacity of 12,800 tons, with each unit rated at 3,200 tons. Water-cooled technology offers greater energy efficiency than conventional air-cooled alternatives because of water’s superior heat-transfer properties and its ability to reject heat at lower ambient temperatures.

The first phase will include three chillers, providing sufficient capacity for Concourses D and E while retaining a third unit for redundancy. The chillers will operate on a rotating schedule to distribute running hours evenly and allow maintenance without compromising cooling provision.

The cooling system is expected to come online earlier in 2028 to support interior construction at Concourse D, ahead of the plant’s formal commissioning alongside the concourse opening in late 2028.

A fourth chiller will be installed in the early 2030s as construction of the O’Hare Global Terminal progresses. Cooling for the terminal will be supplied jointly by the Midfield Cooling Plant and the existing facility near Terminal 3, maintaining additional capacity within the system.

O’Hare’s existing Heating and Refrigeration Plant will continue to provide heating for the entire terminal complex, including the new ORDNext facilities.

The Midfield Cooling Plant forms part of the wider infrastructure investment supporting O’Hare’s expansion, helping provide the capacity required to accommodate new passenger facilities and airport operations.

Further information on the programme is available at https://ordnext.org/.