Innovation Winter 2025/26

The Chief Dan George. P hoto : SAAM T owage

Collaborating with Corvus Energy, a Vancouver-founded firm specializing in production of marine lithium-ion systems, RAL equipped the resulting ElectRA 2800 with Corvus’ battery systems. Each vessel carries more than five megawatt-hours of energy in nickel-manganese cobalt (NMC) and graphite cells, providing enough power for several ship assists on a single charge. “Short runs, lots of starts and stops, always coming back to the dock; it’s exactly the kind of work electric propulsion is good at,” said Turner. In 2023, after three years of design and manufacturing effort, North America’s first electric tugboats pulled into Vancouver, after a two-month journey at sea from the tugboat’s manufacturing shipyards in Türkiye. Today, nine of these electric tugs are in operation in ports ranging from Sweden to Chile and locally in North Vancouver, making up a significant share of the world’s existing battery tugs. The tugboat engineering process Building some of the world’s first fully electric tugs required significant redesign and space redistribution. “The biggest challenge was fitting in enough batteries,”

Turner said. “We were fairly familiar with using batteries in our designs from hybrid mechanical boats, but this was a different scale.” With required power supplies of 3,000 kWh and more, thousands of kilograms of batteries were needed on a typical electric tugboat. Switchboards similarly ballooned with the change to an electrical system, jumping from approximately four linear metres on a typical internal combustion engine to 16 metres on an electric motor. “A 28-foot electric tug could likely have been 24 feet on a traditional boat,” said Phillips. Much of the engineering effort of designing the electrical vessels went into designing for weight requirements, load distributions, and new system configurations. At the same time, working with an electric engine also provided new flexibility. “You’re not constrained in the same way mechanically, where the engine has to be aligned with the shaft,” said Turner. “There’s freedom in that respect to designing electric vessels where components are more independent of each other.” Fire safety was another complex aspect of the design. Like all lithium-ion systems, marine batteries carry a risk of thermal runaway: a chain reaction triggered by

Innovation Winter 2025/26

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