The CQ450 provides 450 kWh of battery storage and can deliver charging power of up to 240 kW. Unlike a permanently installed charging system, the unit can be moved between locations as operational requirements change.
Tidal Transit is using the system to support overnight charging of e-Ginny while limiting the vessel’s dependence on the immediate capacity of the local electricity network.
That flexibility could be useful for operators introducing electric vessels across several ports, particularly where berths were not originally designed to accommodate large new electrical loads.
Fellten’s wider Charge Qube range includes the 160-kWh CQ160, while higher-capacity models of up to 1 MWh are planned. The systems have also been positioned for applications including EV fleets, manufacturing, emergency services and sites with restricted grid connections.
Using the same approach for marine charging brings battery capacity directly to the dock rather than requiring operators to wait for a permanent high-power connection.
For ports, mobile energy storage could also offer more control over when electricity is drawn from the grid. A battery can potentially recharge when network capacity is available and deliver that stored power when a vessel requires a higher charging rate.
The economics, however, will vary considerably by location. Electricity tariffs, battery utilization, transport requirements, charging schedules and equipment costs will all influence whether mobile storage makes commercial sense.
The battery also has to be recharged, meaning it does not remove the need for adequate electricity supply over the longer term.
The charging trial is part of Tidal Transit’s wider e-Ginny project, which involved converting the diesel-powered Ginny Louise crew transfer vessel to fully electric propulsion.
Crew transfer vessels regularly carry technicians and equipment between ports and offshore wind farms, making them a closely watched use case for marine electrification.
Their operating patterns also make charging particularly important. Vessels can face demanding schedules, frequent journeys and relatively short turnaround periods, creating a requirement for dependable access to sufficient power.
Tidal Transit has argued that electric vessel development is beginning to move faster than some of the infrastructure required to support it. Mobile battery systems are therefore being assessed as a way to introduce charging capacity while permanent port and grid projects continue.
For vessel operators, that could reduce the risk of bringing an electric vessel into service before high-capacity charging is available at every location it needs to use.
The e-Ginny program is also examining offshore charging, allowing Tidal Transit to test how electric crew transfer vessels could be supported both at the quayside and closer to offshore wind operations.
Whether mobile batteries ultimately become temporary infrastructure or a regular feature of port energy systems remains uncertain. Their role could depend on how quickly grid capacity expands and whether operators find value in retaining flexible storage even after fixed charging equipment is installed.
What the deployment does make clear is that vessel electrification cannot be considered in isolation. As more commercial electric vessels enter service, ports will need charging strategies capable of keeping pace with them.
