Standby Power System Study

Standby Power System Study

Location: Chicago

Client: Chicago Department of Aviation

Completion Date: Ongoing

Burns & McDonnell performed an inspection and evaluation of the electrical and standby power systems of O'Hare International Airport's Heating and Refrigeration (H&R) Plant. The H&R Plant supplies high temperature water and chilled water to the mechanical systems in the passenger terminals and concourses. The electrical system powering the H&R plant consists of several medium-voltage utility services that are interconnected to minimize the impact of the loss of any of the individual services. The turbine-generator powered standby power system in the H&R Plant provides final reserve power for the passenger terminals and concourses.

The electrical phase verified several systems. It included reviewing and validating all electrical single-line schematic diagrams for the H&R Plant, plus the elevated parking structure and the airfield fire and rescue stations. All equipment shown on the diagrams, including the standby power distribution system, were verified by an inspector. Changes to the electrical system were documented, and the diagrams updated to reflect present conditions.

The H&R Plant has six diesel-fueled turbine-generators to provide power in the unlikely event of the loss of several of the electric utility supplies. Through the standby power distribution system, these generators ensure that the H&R Plant and the passenger terminals and concourses are able to operate even during an extended electric utility outage.

A detailed list of the loads supported by the standby power system was developed as part of this project. In addition to the generators themselves, the mechanical systems that support generator operation, such a draft fans, fuel storage and pumping, were also inspected. Once the inspections were complete, overall condition and age of the components the standby power system were evaluated and compared to present City of Chicago and Federal Aviation Administration code requirements, technological advances, and security considerations. Recommendations affecting the electrical power distribution system, turbine-generators and their controls, and the standby power distribution system were developed and provided to the Chicago Department of Aviation.

The second phase of the project focuses on the condition of the existing mechanical system components and their operation as a complete system. The condition, reliability and remaining service life of the hot and chilled water systems will be evaluated. The efficiency of each system will be evaluated in light of present equipment technologies to identify opportunities to improve system reliability, economy and responsiveness. The analysis will identify both anticipated heating and cooling needs as the Airport Master Plan is implemented as well as any existing deficiencies. The evaluation will use a lowest cost of ownership approach to best use available airport funds and dovetail with replacements that may be prompted by equipment obsolescence. The report will include short- and long-range utility master plans, including forecast capital requirements and schedules to implement the plans.