Under cold, windy and rainy skies, Seattle-based Foss Maritime on Jan. 23, 2009 introduced the first-ever diesel-electric hybrid tugboat. The unveiling came during a ceremony, attended by around 300 leaders from the ports of Long Beach and Los Angeles, the state of California, and Foss Maritime Company, who gathered with business, government and media representatives to welcome the world’s first true hybrid tug, Foss’ Green Assist™, to southern California. at the Foss berth on Pier D at the
Foss says that the new green-and-white tug, named the Carolyn Dorothy, designed by
The idea had been kicking around Foss' offices since 2006, based on the knowledge that tugboats tend to run on full power only 7% of the time and waste their 5,000-plus horsepower by idling 50% of the time. Knowing that railroads were moving to electric propulsion, Foss initially looked at switching locomotives, which are used to move trains inside rail yards.
The engineering firm, Aspin Kemp & Associates of
While it operates like a standard ship berthing tug, the system's design would enable most existing tugboats to switch to the diesel-battery setup through a retrofit.
The 78-foot-long, 34-foot-wide dolphin-class tug cost upward of $8 million to construct, with the Port of Long Beach and Port of Los Angeles contributing a combined $1.3 million toward the construction. The ports provided the funding as part of the Technology Advancement Program, a component of their San Pedro Bay Ports Clean Air Action Plan.