A Case Study and Recommendations for Passenger Ferry Electrification and Berthing Upgrades

Abstract: A large portion of the United States' ferry systems rely on diesel powered vessels. As transportation agencies focus on emissions reductions and grant funding becomes more accessible, ferry vessels are being overhauled or replaced with electric or hybrid propulsion systems. The combination of new electrical demands, charging equipment, and altered vessel geometry require significant planning and upgrades for the terminal shoreside infrastructure.

The Maine Department of Transportation is in the process of replacing and upgrading the current ferry vessel that operates between the communities of Lincolnville and Islesboro. This new vessel will have plug-in hybrid propulsion. The new vessel will also be roughly25 percent longer than the current ferry, at approximately 200 feet length overall versus 160 feet. Given the need for the larger boat and the State of Maine’s goals of modernizing their rural ferry system, the corresponding terminal facilities must be upgraded. In coordination with the design of the new vessel, the terminal upgrades are designed and coordinated to ensure that the new vessel can be safely accommodated, has adequate rapid charging capabilities and infrastructure, and is adequately sheltered from future weather events.

These upgrades will serve multiple purposes: the first will be the modernization of facilities that were originally constructed in 1959, and the second will be to provide the infrastructure required to accommodate the larger electric vessel. The current vessel, constructed in 1987, is undersized and is nearing the end of its useful life. The larger, replacement vessel will accommodate additional vehicles and passengers, reducing the current capacity issues. Severe weather events will also be addressed as part of the terminal upgrades; additional berthing protections such as wave screens are to be installed to improve wave tranquility during normal operations, and shelter the vessel when moored in storm events. These protections provide added flexibility of allowing operational services to continue in increasingly harsher conditions, which increases the reliability of the rural service to the Islesboro communities.

Facility improvements include the rapid charging infrastructure required for the new plug-in hybrid vessel, which consists of new underground electrical and communication services, installation of rapid charging equipment on a dedicated dolphin, installation of trickle charges at both landings, and construction of multiple transformers and other electrical equipment. Marine structures upgrades, which accommodate the larger vessel and provide more sheltered berthing conditions, include the construction of new berthing dolphins, fenders, and wave protection at each terminal location.

The infrastructure upgrades are scheduled to be constructed in 2025, with preliminary contractor construction feedback available for inclusion in the Ports Conference Presentation. The Lincolnville and Islesboro ferry electrical infrastructure upgrades and charging system will be compared with other recent ferry electrification projects completed by the project team in Maine, British Columbia, and Ontario. Comparison areas include cost, maintenance, and operational parameters. The authors’ recommendations for best practices for future ferry electrification infrastructure projects will be shared.

How does this project / topic contribute to the advancement of the industry and profession?: In the US and globally, transportation agencies are adopting electric and hybrid electric vessels for their ferry fleets. This trend is expected to continue to accelerate. This paper provides a case study and best practice recommendations for planning the terminal infrastructure supporting the transition to electric vessels at existing ferry terminals.

Does the project / topic implement new and innovative techniques, materials, technologies, and delivery methods?: Yes, electric ferry charging systems and corresponding electrical demands/infrastructure are emerging technologies.

What was the most challenging aspect of your project / topic and how did you handle it to ensure success?: Coordination of project stakeholders and designers was amongst the most challenging aspects. In addition to the transportation agency project owner, there is a separate vessel operations team, naval architect designer, charging integrator, and permitting team. The new vessel and shore-side infrastructure is also being developed and procured on separate timelines. Regular coordination meetings as well as identification and tracking of key project parameters allowed project development to continue smoothly.

Who is the target audience for this paper?: Ferry system owners and operators, ferry terminal planners, electrical designers, marine structures engineers