First all-electric harbor tug in United States is powered by ABB propulsion

  • A new chapter in vessel electrification begins as all-electric, battery-powered eWolf was christened this week at the Port of San Diego
  • Owned and operated by Crowley, eWolf will use its ABB electric propulsion system to sustain zero-emissions operations
  • Using all-electric tug propulsion will significantly reduce greenhouse gas emissions as part of Port of San Diego’s Maritime Clean Air Strategy

27 June 2024 – The ABB powered all-electric tug eWolf has been christened this week at the Port of San Diego, California, marking a new chapter in vessel electrification in the United States. Owned and operated by Crowley, eWolf features an end-to-end electric propulsion system from ABB including a 6.2-megawatt-hour energy storage system (ESS). This allows the vessel to achieve 70 short tons of bollard pull with zero emissions and complete a full day of work on a single charge. Given electricity is cheaper to produce on shore than onboard a vessel, the ESS also minimizes operating costs. The eWolf will significantly reduce greenhouse gas emissions in the port area of San Diego, replacing a tug that consumed over 30,000 gallons of diesel per year.

eWolf christening ceremony at the port of San Diego – Image credit ABB

Crowley selected ABB as the full systems integrator for eWolf. The vessel was designed by Crowley’s engineering services group in collaboration with ABB and built by Alabama-based Master Boat Builders, Inc. It was delivered in January 2024.

The eWolf was developed through a partnership among the Port of San Diego, San Diego County Air Pollution Control District, the California Air Resources Board (CARB), the U.S. EPA and the U.S. Maritime Administration.

“The eWolf’s ground-breaking design and innovative technology is a milestone for the entire maritime industry, showing that high performance and zero-emissions can serve ship operators’ modern supply chain needs,” said Cole Van Gundy, Vice President, Crowley engineering services. “The first all-electric ship assist tug was achieved through collaboration that spanned across the industry and government sectors, showing the power of public-private partnerships to produce the advances that will lead the cleaner, more powerful future in maritime.”

“We’re thrilled to see the first all-electric tug in the U.S. enter into service in the Port of San Diego as it checks off a signature goal of our Maritime Clean Air Strategy,” said Chairman Frank Urtasun, Port of San Diego Board of Port Commissioners. “The eWolf adds to the work the Port and our partners are doing to significantly reduce emissions on and around San Diego Bay and demonstrates our commitment to clean, efficient maritime operations.”

In addition to the ESS, ABB supplied its award-winning Onboard DC Grid™ power distribution platform for optimized energy use, the ABB Ability™ Marine Diagnostic system for continuous preventive and predictive monitoring of equipment, and ABB Ability™ Marine Pilot products to enhance safety and reduce crew workload. Pilot Vision situational awareness provides 360-degree visibility from the pilot’s station, while Pilot Control enables maneuvering support. ABB’s scope of supply also covered transformers, propulsion motors, azimuthing thrusters, and low-voltage switchboards alongside design support, engineering, project management, and commissioning.

“At ABB, we are leading full systems integration and advancing the adoption of electric, digital, and connected technologies in the maritime industry,” said Bruce Strupp, Vice President Marine Systems US & Canada, ABB Marine & Ports. “We pioneered the first fully electric ferries built in the United States and have now successfully delivered the country’s first electric tug. We are thrilled to have collaborated with Crowley engineering services on the development of eWolf from concept to delivery. Crowley’s values are well in line with our own as we continue working towards maritime decarbonization while maintaining crew safety. The collaboration was therefore a great success.”


ABB’s Process Automation business automates, electrifies and digitalizes industrial operations that address a wide range of essential needs – from supplying energy, water and materials, to producing goods and transporting them to market. With its ~20,000 employees, leading technology and service expertise, ABB Process Automation helps customers in process, hybrid and maritime industries improve performance and safety of operations, enabling a more sustainable and resource-efficient future.

ABB is a technology leader in electrification and automation, enabling a more sustainable and resource-efficient future. The company’s solutions connect engineering know-how and software to optimize how things are manufactured, moved, powered and operated. Building on over 140 years of excellence, ABB’s more than 105,000 employees are committed to driving innovations that accelerate industrial transformation.