Case Study: Seattle Waterfront Networked Microgrid Evaluation - Case Study for Port Electrification Handbook

Tuffner, Francis K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000219609663); Idso, Shannon K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)]

doi:10.2172/2574831

DOE OSTI · 2574831

Case Study: Seattle Waterfront Networked Microgrid Evaluation - Case Study for Port Electrification Handbook

Tuffner, Francis K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000219609663)·Idso, Shannon K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)]

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Abstract

Many ports and waterfronts are evaluating alternative electrification efforts, including electrification of passenger and vehicle ferries. In Seattle, the Washington State Department of Transportation, in conjunction with Seattle City Light (the local utility) and the Port of Seattle, are working to deploy a hybrid electric ferry and provide charging at Seattle’s Colman dock. As part of this ferry electrification effort, Seattle City Light is considering including a large battery energy storage system (BESS) to help “buffer” the ferry charging. The “buffer” provides energy arbitrage and spreads out the large amount of power needed to recharge the ferry to times when the ferry is out of the dock – rather than one very large peak for 15 minutes, the battery storage allows it to be a smaller power value over a longer duration. This initial BESS concept served as the jumping off point to explore an expanded microgrid concept via a notional test system that incorporates additional distributed energy resources (DER) and infrastructure upgrades to the local distribution infrastructure at the Seattle Waterfront and neighboring Port of Seattle properties. This case study examined the potential for secondary use of the BESS within a networked microgrid during the scenario of a large-scale power outage, such as a natural disaster.

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Tuffner, Francis K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000219609663), Idso, Shannon K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)]. 2025-04-15. Case Study: Seattle Waterfront Networked Microgrid Evaluation - Case Study for Port Electrification Handbook. https://doi.org/10.2172/2574831

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