All American Marine (AAM) has inked a deal for the construction of a new 128'x30' hybrid-electric 600-passenger vessel for the Red and White Fleet in San Francisco. The contract for the new aluminum monohull Enhydra was signed during the recent Passenger Vessel Association annual meeting in Seattle.

“We are proud to offer a hybrid propulsion system that truly works with instant and tangible benefits,” Joe Hudspeth, AAM’s vice president of business development, said in a statement announcing the contract.

AAM’s latest contract follows an earlier announcement that it would build a 500-passenger aluminum monohull tour boat for Argosy Cruises, Seattle. Both operators were originally pursuing construction contracts for steel monohulls, but AAM was able to show considerable savings in construction and maintenance costs with an aluminum design, while ensuring delivery of a solid hull structure. Argosy will take delivery of its vessel in late fall and the Red and White Fleet will receive its new craft in late spring 2018.

The new vessel for Red and White Fleet will be the first aluminum hulled, lithium-ion battery-electric hybrid vessel built from the keel up under Coast Guard Subchapter K passenger vessel regulations and the latest guidelines for structural fire protection. The vessel is specifically designed for harbor tours of San Francisco Bay and the Golden Gate Bridge. Guests on board Enhydra will be able to experience amazing views of the bay and cityscape from each of the three decks. The second level offers a full wrap around viewing deck with access to the enlarged bow foredeck. The top deck is completely open and offers plenty of outdoor seating for sun soaking or just relaxing.

The shipyard partnered with BAE Systems to design and integrate the complete battery electric hybrid system. BAE Systems will supply its HybriDrive propulsion system that includes a generator, control system, and AC electric traction motor. The generator will mount to a variable speed Cummins QSL9 diesel engine, producing 410 hp at 2,100 rpm. The motor generator offers diesel-electric operation of the AC traction motor, which is coupled directly to the propulsion shaft. With this configuration, torque is immediately available for the propeller and the speed can be precisely controlled without the need for a reduction gear.

The hybrid system will also utilize battery power from two 80-kW lithium-ion battery packs. The batteries will come from Corvus Energy and are supplied under its next generation Orca Energy line. The BAE HybridDrive system can automatically utilize full electric battery operation at slower speeds and when maneuvering in and out of the harbor. At higher speeds, the generator will automatically engage and augment the additional power demands of the traction motor. The battery system is sufficient to meet the entire demand of the vessel’s hotel load while at the same time providing silent and emission-free operation of the propulsion system during an evening sunset cruise.

Red and White Fleet’s vice president of operations, Joe Burgard, said he's eager for passengers to experience San Francisco Bay from the silent decks of the Enhydra in 2018. "We see the propulsion configuration on the Enhydra as phase one in our move toward the full electrification of our fleet. Stay tuned for phase two.”

AAM is celebrating its 30th anniversary and will move into a new purpose-built shipbuilding facility at nearby Squalicum Harbor in April.


Ken Hocke has been the senior editor of WorkBoat since 1999. He was the associate editor of WorkBoat from 1997 to 1999. Prior to that, he was the editor of the Daily Shipping Guide, a transportation daily in New Orleans. He has written for other publications including The Times-Picayune. He graduated from Louisiana State University with an arts and sciences degree, with a concentration in English, in 1978.