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Master Boat Builders of Coden, Alabama, has begun construction of what will be the first all-electric ship assist tug to sail under the US flag.
The 82-foot (25-metre) harbour tug will be completed and ready for service in mid-2023 at the Port of San Diego as part of the fleet of Crowley Maritime Corporation.
The vessel will be constructed under the design and on-site construction management of Crowley Engineering Services, Crowley's naval architecture and marine engineering group.
ABB will supply an end-to-end electric propulsion system to sustain emissions-free operations. The arrangement will include a 6MWh energy storage system that will allow the tug to achieve 70 tons (63.5 tonnes) of bollard pull without emissions.
ABB said the battery will allow the tug to complete a full day of typical work before there is a need to charge.