Sea-Tac Airport Centralized Preconditioned Air Project, SeaTac, Wash.
The project significantly reduced on-plane energy use at the busy facility by shifting the power source for heating and cooling from jet fuel to low-carbon airport electricity, the project team says.
Sea-Tac Airport, the 15th busiest in the nation last year, serves 34.7 million passengers annually. The team says the project did not impact the airport's operations.
Airplanes usually burn large amounts of fuel to keep cabin temperature between 68 degrees and 70 degrees, regardless of outside weather conditions. As a result, jet auxiliary engines across all gates at Sea-Tac Airport emit enough carbon dioxide (CO2) to equal about 8,000 cars on the road in a year, says Lydig Construction.
The $36-million project is expected to save the owner about $13.75 million in annual fuel costs with a CO2 emission reduction of more than 50,000 metric tons a year, the team says.
The Preconditoned Air Project uses a system of chillers, heaters and pipes that provide both heated and cooled air to aircraft from a central plant located 30 ft below the airport's main terminal.
With this new system in place, flight crews are able to turn off aircraft auxiliary engines and plug in at the gate to receive the preconditioned air.
Designing and building the complex piping installation was a key challenge. The system runs through multiple terminals and 73 aircraft gates. The team installed a total of 15 miles of piping at the 600,000-sq-ft facility.
Pipe routes, hangar locations and other assembly components were designed "through a sea of meandering conveyor belts and existing utility infrastructure that remained operational throughout the course of the project," Lydig Construction says.
More than 4,000 hours of labor were required for completing field research and for preparing the final equipment layout, hydronic piping system routing, pipe support and piping systems fabrication shop drawings. But the effort is credited with enabling major components to arrive on site ready for final field installation without requiring additional modifications, the team says.
Four new 300-ton centrifugal water chillers enable the facility's mechanical system to produce water chilled to 20 degrees for passenger-gate preconditioned air units. The distribution system includes about 70,000 linear ft of hydronic piping.
The system is routed to the passenger gate units at both concealed and exposed ramp levels and through exposed rooftop installations. Securing pipe at a high level and away from ground support equipment saved the Port of Seattle several million dollars in added costs, Lydig says. The system's central computer also minimizes some operations.
During normal power demand conditions, the facility's mechanical system operates at night when electrical consumption costs are considerably lower. Chilled water serves the new thermal storage equipment, producing ice storage that allows the airport to meet aircraft cabin cooling needs without operating new centrifugal water chillers at times of peak power demand.
Preconditioned air is delivered through a telescoping air duct and then through a flex duct to the fuselage.
Judges noted the site's 24/7 operating challenge and cited the project's "very clean and well-coordinated" piping and conduit.
Owner Port of Seattle
General Contractor/Contract Manager Lydig Construction
Lead Design Firm Stantec