Case study: Airport electrical system upgraded

A Houston airport renovation added switchgear for additional electrical support

By Taiwo Atoki, PE, LEED AP July 26, 2022
Courtesy: Page

Page is currently working at George Bush Intercontinental Airport (known as IAH) to provide architecture and engineering services for a renovation and expansion of the international Terminal E and Federal Inspection Services building.

The project includes more than 200,000 square feet of terminal expansion and more than 200,000 square feet of renovations to the existing terminal building. The project scope includes the international arrivals area, ticketing, security checkpoint, baggage handling systems and vehicle curbs. The scope encompasses mechanical, electrical and plumbing services with Page’s multidisciplinary team to achieve a high level of coordination while increasing the passenger experience in both new and renovation areas.

Figure 6: Within the George Bush IAH – Federal Inspection Services renovation, the airline ticketing office looks over the departure ticketing hall below. Courtesy: Page

Electrical design approaches for this project include the provision of 2,500 amperes main-tie-main switchgear fed from two 2,000 kilovolt amperes transformers with the source of power derived from two independent utility services to accommodate the new baggage handling system and other substantial electrical loads.

During the project value engineering, the life cycle cost analysis resulted in the use of draw-out-mounted circuits breakers for the two mains and tie-breaker while the rest of the breakers were designed with molded-case circuit breakers. This practically replaced the switchgear with a switchboard for a significant cost-effective solution.

Based on the project’s complex nature, two additional 1,600 ampere-rated switchboards were added to supplement the power needs. The two switchboards were fed from the existing FIS switchgear line-ups located at the east of the existing building. The additional services provided an opportunity to serve the enabling part of the project and became a permanent service for the new FIS expansion.

From the downstream of the switchboards, various panelboards and dry-type transformers were strategically located close to their load centers. Harmonic mitigating transformers were used in the areas with many computer workstations.

Figure 7: The addition of switchboards, panelboards, dry-type transformers and an uninterruptible power supply system with lithium-ion batteries was designed to facilitate the new upgrades and expansion of the electrical system at the arrivals terminal in George Bush IAH. Courtesy: Page

Two central uninterruptible power supplies in an N+1 parallel configuration were provided to serve all the main and intermediate distribution frame room equipment. The UPS outputs were paralleled to a common bus in such a way that if one unit fails, the other can manage the paralleling while any defective UPS unit is being repaired. The UPS was integrated with lithium-ion batteries to optimize reliability and to ensure significant cost-of-ownership saving is guaranteed.

Lighting inverters were dedicated to each building floor level for emergency egress lighting, exit signs and life safety needs. The lighting system was designed to provide a visually comfortable high-quality illuminated environment for the passengers and airport staff. The lighting design commitment ensured a reduced level of glaring and brightness was produced from the LED type energy-efficient fixtures with a new lighting control system coupled with daylighting advantage in the glazing wall of departure level with ease of maintenance.

Page is collaborating with HOK (architect) and Hensel Phelps (construction).

Author Bio: Taiwo Atoki is a lead electrical engineer and associate at Page.