Epstein-Designed Emergency Backup System for O'Hare

The recently completed O’Hare International Airport (ORD) Emergency & Standby Power Systems project is yet another fine example of Epstein’s ability to deliver an inspired piece of public infrastructure.

For this project, which provides back-up power to the airport, Epstein served as the architect and engineer for this 2-building complex, which replaced a system that was located within ORD’s H&R Plant and was originally installed in the 1960s. The driving force for the replacement of the old back-up power system was that it used technology that was so dated that the airport couldn’t find replacement parts for much of the equipment.

The Epstein-designed replacement, featuring two buildings, one to house the new generators and one to house electrical switchgear, is more computer driven and digitally based. It increases the existing system capacity from 8-10 megawatts to 18 megawatts, which is enough to power several thousand homes. As a result, ORD has greater system functionality and efficiency during emergencies in which normal operations have been impaired.

Originally, these new buildings were planned to be in the back of the airport, near the airfield and out of sight. As the project evolved, however, it became clear a larger space was needed and, therefore, a prominent site just north of the H&R Plant was chosen.

With this new site, which is visible to all visitors exiting the airport by Terminal 3, Epstein’s architects developed a concept that compliments the main two components of the modernist H&R Plant – steel and glass. This approach ties all three buildings together, resulting in a unified look. Therefore, the new generator building is clad with black aluminum fins that resemble the steel components of the H&R Plant. And the switchgear building is a glass cube made entirely out of channel glass. The design also purposely plays off of the contrast between light and dark colors, creating a pleasing finish among them. These new buildings also sit on a slightly elevated platform, which provides security for the buildings while also adding to the prominence of the structures.

The generators themselves can be likened to diesel locomotive engines as they produce the power. The electrical distribution, or switchgear, dispenses the power throughout the airport. Typically, the two components exist in different rooms of the same building. Epstein’s 2-building approach, along with the internal design of the buildings and systems, are part of a compartmentalized method to minimize the chances of a catastrophic event taking down the entire system.

The six generators are enormous and their building is split in two halves, with three generators in each half. Each half also houses a fuel tank, which feeds the generators with the thousands of gallons of fuel they require to continuously run at full-speed. Furthermore, the wall separating the two generator rooms is a 2-hour fire-rated wall; therefore, it can withstand a fire burning on one side for 2 hours before it starts to penetrate the other side. The walls separating the generator rooms from their tank rooms have a fire-resistance rating of 4 hours, an increase due to the nature of the fuel inside.

The switchgear building is designed in the same manner: split in two halves. There is also a 2-hour fire-rated wall separating those rooms. The fire-resistance separation walls are comprised of concrete masonry units (CMU), which are standard rectangular blocks used in building construction, and are 8 inches thick.

This ORD complex represents, once again, how Epstein’s designers and engineers can take what is typically treated as a mundane piece of infrastructure and elevate it into something grand and meaningful.