Kirby Inland Marine LP, Channelview, Texas, the largest inland tank barge operator in the U.S., on Friday christened what is said to be the nation's first electric hybrid inland towboat.
The 73.6'x30' Green Diamond is undergoing final commissioning and is expected to be in service within the month, said a Kirby spokesman. The vessel is time chartered to Shell Trading (U.S.) Co., while Shell Energy Solutions, which installed the plug-in charging station at Kirby's Old River Fleet Dock, will provide the electrical power for the vessel.
"We are excited to be the first to market with a plug-in hybrid inland towing vessel,” Christian O’Neil, president of Kirby Marine Transportation Group, told representatives of Kirby, Shell, assorted vendors, the U.S. Coast Guard and others gathered for the christening ceremony. “Barge transportation is already the cleanest and greenest way to move a wide variety of cargoes in America, and we are working to make it cleaner and greener."
The vessel was designed and built by Kirby-owned San Jac Marine, also of Channelview. Two Danfoss 450 KW electric motors deliver propulsion for the Green Diamond with a broad torque curve beyond that of a conventional towboat. The motors are driven by a Corvus Orca Series battery system with 1,243 KwH of electrical capacity or, when needed, two onboard Caterpillar gensets with a combined 1,130 kW of power capacity. Stewart and Stevenson provided the power management system.
"Depending on the load, the towboat can operate solely on battery power with zero emissions," said San Jac VP Mitch Jones. "The generators provide excess capacity that's stored in the batteries and used when needed."
Kirby says the vessel leverages the inherent benefits of a diesel-electric design combined with an energy storage system. Based on modeling, when operating on dockside supplied power, fuel use can be reduced by nearly 80% with an up to 95% reduction in noxious emissions. Engine run time can be reduced between 93% and 98%, compared to a conventional diesel-fueled inland towing vessel, Kirby officials said.
"Three years ago, we decided to design a new boat, one that would revolutionize the towing industry. What we turned out here is a true hybrid vessel and unlike any that's ever been built in the United States," Jones said. “We are already looking at building follow-on vessels."