The project: A first-of-its kind battery-based system in the U.S. that prevents split-second voltage sags from inbound power lines from shutting down the plants critical operating pumps. The new electrical room includes a 16.8-megawatt battery system integrated into the electrical system of seven pumps and operates continuously to provide consistent power to the plant. A solar array centrally located on the campus was included to provide power for lighting, heating, ventilation, and air conditioning.

The goal: Enhance power stability to two critical pump systems to help the plant ride out temporary power disruptions. The system also needs to reduce emergency bypasses of untreated wastewater to Puget Sound, especially during severe storms.

Design approach: IMEG worked closely with the owner and design team, providing on-call energy consulting for the overall site. The team also provided options for code compliance.

Challenge: Code compliance required approval from the city for an alternative compliance pathway. Solution: IMEG provided energy modeling to determine additional energy use if the project failed air leakage testing. Additional PV capacity was then added to the centralized system to provide an offset to the potential energy consumption associated with a higher-than-code-allowance air infiltration scenario.

The outcome: The campus will benefit from the new consistent and stable power from the battery system.