Schottel to power all-electric tug eWolf

While hybrid and alternative-fuel tugs are becoming increasingly common in the quest for greater efficiencies and cleaner operations, some operating profiles open the possibility of employing all-electric tugs and while a handful are currently listed in Europe and beyond, this US reference introduces a new geographical region for all-electric tugs.

German propulsion manufacturer Schottel has announced that as part of the eWolf package it will supply two RudderPropeller type SRP 430 thrusters featuring the LE-Drive (Embedded L-Drive) and MariHub – the data Internet of Things (IoT) gateway and its monitoring solution. The thrusters will each supply 2,050kW of power via 2.5m diameter propellers developing a bollard pull of 70 short tonnes. The SRP 430 LE thruster features a compact design with an extremely low installation height for the LE-Drive while the omission of the upper gearbox increases mechanical efficiency by around three percent and at the same time reduces fuel consumption.

eWolf’s 6MWh energy storage system will provide sufficient capacity for one full day of normal work without using any fuel, the batteries supplying power to the propulsion systems “almost instantly.” The tug’s systems are designed for fast-changing load requirements and two on-board generators will be provided for emergency use and to enable longer transit legs at reduced speed.

Schottel’s MariHub IoT gateway and monitoring solution will record and analyse signals from sensors, machinery and other components to be certified by Schottel technicians. Along with ProCMS (condition monitoring system) MariHub allows early detection of irregularities in the propulsion system, a predictive maintenance approach that will “significantly increase” the availability of the vessel.

Construction of eWolf is underway at Master Boat Builders shipyard in Coden, Alabama for US operator Crowley with completion scheduled for mid-2023 whereafter it will operate at Port of San Diego, California, Garrett Rice, president Master Boat Builders stating: “Today is also a remarkable milestone for the entire US maritime industry as we work toward providing ground breaking net zero-emission maritime capabilities.” eWolf is designed by Crowley Engineering Services and the tug will allow fully-electric operation while maintaining full performance capabilities with an integrated electrical package provided by Switzerland-based automation company ABB.