Corvus Energy battery system powers the Crowley eWolf, the first all-electric harbor tugboat in the United States

10 July 2024, USA — Corvus Energy is pleased to have supplied the battery system for the Crowley eWolf, the first fully electric ship assist harbor tugboat in the United States.

The groundbreaking eWolf tug, designed by Crowley and built by Master Boat Builders for operation in the Port of San Diego in California, is powered by an integrated electrical propulsion system from ABB that incorporates a Corvus battery system. 

Corvus Energy involvement, powering zero-emission operations

The eWolf is equipped with a Corvus Orca ESS, the most installed marine energy storage system worldwide, used onboard over 700 maritime vessels around the world. The eWolf is outfitted with a 6.2 MWh Corvus Orca system and is capable of operating daily at full capacity using battery power alone. Battery-powered operations require zero fuel and produce zero emissions, resulting in significant environmental and fuel-saving benefits.

Crowley anticipates the tug will “generate 178 tons less of nitrogen oxide (NOx), 2.5 tons less of diesel particulate matter and 3,100 metric tons less of carbon dioxide (CO2) over the first 10 years of its operations – the equivalent of removing 350,000 gallons of gas from use, according to EPA calculations.” (source

“Corvus Energy is pleased to have contributed to this landmark project for Crowley and the Port of San Diego by supplying the battery system, part of the ABB integrated electric propulsion system onboard the eWolf” says Corvus Energy SVP Americas, Tor-Gunnar Hovig.

Advanced battery system monitoring technology

To optimize battery performance over the lifetime of the system, cloud-based technology is used to continuously monitor ESS function and provide critical performance insights through the Corvus Energy Vessel Information Portal. 

The online monitoring tool uses big data, machine learning and algorithms to support predictive maintenance, optimized system use and proactive troubleshooting. A secure digital solution, the Corvus Orca ESS used with the Corvus monitoring system was awarded Cyber Security Type Approval from leading maritime classification society, DNV.

Electric Tugboats in the United States

Worldwide, tugboats were among the first maritime vessels to adopt battery technology due to their near shore operations and ability to recharge regularly.

In the United States, the Crowley eWolf and Port of San Diego are leading the way. In turn, several other ports are currently pursuing federal funding to invest in fully electric tugs under the “U.S. Green Ports Program.” With anticipated U.S. federal funding support and increasing focus on carbon reduction, the eWolf is anticipated to be the first of several electric tugboats operating in the United States within upcoming years.

At the forefront of marine battery technology development, over half of the hybrid electric and fully electric maritime vessels worldwide use a Corvus system. As more battery-powered vessels are planned in the United States, Hovig indicated that “Corvus Energy is well positioned to support, by offering proven technology, operational expertise, and US-based manufacturing capacity. Corvus has a production facility in the United States, located in Bellingham, Washington, that produces the Corvus Orca ESS and is fully Buy America and BABA compliant, a key qualifier for U.S. federally funded initiatives.”

The Crowley eWolf, the first all-electric harbor tugboat in the United States. Photo taken on the day of the vessel christening.
Corvus Energy battery system onboard the Crowley eWolf electric tug.
Corvus Energy Vessel Information Portal, cloud-based ESS monitoring tool.

About Corvus Energy

Corvus Energy is the leading supplier of energy storage systems (ESS) for maritime, offshore and port applications. Corvus Energy offers a full portfolio of energy storage and fuel cell systems, suitable for almost every vessel type, providing power systems in the form of modular lithium-ion battery systems and Hydrogen PEM fuel cell systems. Corvus Energy has unsurpassed experience from more than 1200 projects. More than 50% of the world`s vessels with zero-emission technology are equipped with Corvus Energy systems.

For more information, please visit corvusenergy.com

Media Contact 

Europe and Asia
Sonja Vernøy Hansen
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Americas
Angela McClellan
Marketing Manager, Americas
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