Curtin Maritime, which provides tug-assist services at the ports of Los Angeles and Long Beach, is preparing to deploy a fleet of U.S.-built hybrid-electric tugs in collaboration with marine electrification company Arc. The vessels are being built at Snow & Company’s Seattle shipyard.
The project represents what the companies describe as the largest commercial deployment of electric workboats in marine industry history and marks a transition away from conventional diesel-powered tugs and harbor craft toward hybrid-electric propulsion.
Industry reports suggest the initiative was motivated in part by California-based Curtin Maritime’s need to comply with strict air-quality standards enforced by the California Air Resources Board (CARB).
Each tug will be powered by Arc’s vertically integrated electric powertrain, delivering more than 4,000 horsepower and supported by a 6-megawatt-hour battery system.
Marine battery manufacturer Corvus Energy says that, depending on battery size and a vessel’s operational profile, hybrid-powered tugs can typically reduce fuel consumption and emissions by 30% to 60% compared with conventional diesel-powered tugboats. With high diesel fuel prices, such reductions could provide an operating-cost advantage.
Corvus says hybrid-powered operations can also improve energy efficiency and reduce engine maintenance. The battery energy-storage system helps level loads on the diesel engine. Less engine run time, supplemented by battery power, results in reduced engine wear and maintenance.
