
COMMISSION AGENDA – Action Item No. _8a__ Page 2 of 7
Meeting Date: July 9, 2019
Template revised September 22, 2016; format updates October 19, 2016.
JUSTIFICATION
The Seattle-Tacoma International Airport’s 12,470V power distribution system is a complex
network of transmission lines, substations, load centers, power centers, and switchgear that
supply electricity to all parts of the Airport.
SCADA systems perform four functions, (1) Data acquisition, (2) Networked data
communication, (3) Data presentation, and (4) Control. The SCADA system provides a safe,
reliable, and efficient method to operate, monitor, and control switchgear remotely. SCADA
systems are crucial for at critical facilities such as airports and hospitals, since they help to
maintain efficiency, process data for smarter decisions, and communicate system issues to help
mitigate downtime.
Project objectives include the following:
• Personnel safety
• Minimize system downtime and associated operational disruption to the airlines and
tenants, including significant reduction in time to recover from full loss of electrical
power, by switching all power loads to the recently completed Alternate Utility
Facility (AUF). The AUF provides 30 megawatts of standby power to Sea-Tac airport,
more than enough power to fully support the airport’s electrical requirements.
• Optimally balance electrical loads across the entire power distribution network
• Record event and meter data for historical reporting and analysis
• Quickly identify and pinpoint problems or potential problems within the system
• Develop and add a new Electrical Command and Control Center (EC3) Room
This project is necessary to meet requirements within national electrical and safety codes that
are enforced by the Washington Department Labor & Industries. The benefits of this project
include meeting code, ensuring worker safety, minimizing breadth and duration of future
power outages, and extending lifespan of electrical circuits and breakers. SCADA systems are
used by industrial organizations and companies in public and private sectors to control and
maintain efficiency, distribute data for smarter decision making, and communicate system
issues to help mitigate downtime.
Using a SCADA system will provide the means and methodology for qualified personnel to
operate switchgear remotely, without unsafe human exposure to the arc flash hazard. In 2014,
new electrical safety regulations were enacted regarding arc flash hazards. Arc flash occurs
when electrical power does not follow its intended path. The resulting explosion can cause
serious injury, or death. The new regulations require quantification of the inherent dangers of
arc flash events. To meet this requirement, the Port completed an arc flash hazard study and
labeled all distribution equipment with the known arc flash hazard data. Roughly 50 percent of
all 12,470V - 480V power distribution centers were determined to have arc flash incident