Corvus Energy is pleased to announce that our participation in the innovative Crowley eWolf zero-emission tugboat project has expanded with an order to supply shoreside battery energy storage systems (ESS) using two Corvus Orca BOBs—the containerized version of its market-leading Corvus Orca ESS—with a total energy storage capacity of 2,990 kWh.

The Crowley eWolf, the first all-electric tug in the U.S., and its shoreside charging infrastructure will go into service in San Diego’s harbor in 2023. Corvus Energy also supplying the 6.2 MWh Corvus Orca ESS on board eWolf. The vessel is under construction at Master Boat Builders, with electrical integration provided by ABB.

“The use of the Corvus Orca ESS shoreside will allow eWolf to charge quickly, potentially avoiding the need to upgrade the electricity grid infrastructure at the port,” remarks Ole Jacob Irgens, Corvus Energy – President Americas. “Since the Orca ESS has a high C-rate, it is capable of discharging quickly and safely so that eWolf will be quickly recharged and returned into service.”

Corvus Orca BOB will be used for shoreside charging of the Crowley eWolf in the Port of San Diego. (Courtesy of Crowley)

The eWolf and the shoreside infrastructure are designed to allow the vessel to operate fully electric with full performance capabilities, as well as draw energy at off-peak hours from the energy grid. The eWolf is a result of a partnership among Crowley, the San Diego County Air Pollution Control District, the California Air Resources Board, the Port of San Diego, the U.S. Environmental Protection Agency and the U.S. Maritime Administration, which all provided financial support and other resources. More information can be found at

"Corvus Energy’s storage system will enable Crowley and our federal, state and local partners to reach our shared commitment of reducing emissions and providing cleaner air for the San Diego community. The innovative technology also will help ensure high performance and reliability as the tugboats serves customers – providing a model for sustainability at ports around the nation,” said Paul Manzi, vice president, Crowley Shipping.

Battery energy storage a viable alternative shoreside energy

The eWolf and its shoreside energy technology are examples of innovative maritime sustainability opportunities to help decarbonize the maritime industry. Crowley and Shell Trading (US) Company (“Shell”) have signed a memorandum of understanding (MOU) focused on supporting alternative energy solutions for shoreside and terminal operations. The Corvus Orca BOB shoreside battery energy storage system reflects this commitment.

“We recognize that the world is in the midst of an energy transition, and we’re working hard to play our part,” said Maarten Poort, general manager of Shell Shipping & Maritime Americas. “As both an investor and customer of Corvus Energy and its innovative ESS products, Shell is proud to support battery energy bunkering as a zero-emission alternative energy solution for shore power.”

Corvus Orca BOB plug-and-play battery room

The Corvus Orca BOB containers will each contain almost 1.5 MWh of energy storage capacity and be capable of “fast-charging” the Crowley eWolf tug. The Corvus Orca BOB is a class-approved, modular battery room solution in standard 20-foot ISO high-cube container size. The complete ESS comes with Orca battery modules, battery monitoring system (BMS), HVAC , TR exhaust, and firefighting and detection system. The “Plug and Play battery room” simplifies integration into any system integrator’s power management system on board a ship.