Hybrid technology to help save fuel and reduce carbon emissions can be applied to almost any form of product that makes use of an engine. One of the latest cases of this is news out of the Netherlands that Damen Shipyards has launched its first ever so called hybrid tug, and may well be the only yard in the world at this point building hybrid tugs for stock.
The ASD Tug 2810 Hybrid, said the shipyard, has a combination of diesel-direct and diesel-electric propulsion that gets the boat an average fuel savings of between 10% and 30% and cuts local emissions by 20 to 60%. The first such tug goes to one Iskes Towage & Salvage, which is based in IJmuiden near Amsterdam.
The tug’s diesel electric propulsion system is designed to deliver “enough power to prevent the main engines of the diesel direct propulsion system from running idle frequently or at low loads.” It consists of 230 kW water-cooled electric propulsion engines between each main engine and the rudder propeller.One fire-fighting/generator set is installed, according to Damen, to feed the electric propulsion engines or to drive a fire-fighting pump. This set engine can deliver 695 kW at 1800 rpm, while each main engine has a maximum power of 1840 kW at 1600 rpm.
The 2810 has an option for on board 100 kWh batteries, designed to let the tug “shut down all the engines during station keeping, manoeuvring and free sailing at low speeds” of up to 5 knots. And in a further nod to a closer to zero emissions tug, solar panels can be added to the deckhouse to charge the 24V battery packs for starting the engines and emergency power for navigation lighting and radio equipment.
Damen Shipyards, which hopes to have a second hybrid tug built by the end of next year, has also been looking into other ways to green some of the ships it builds. These options have included the idea of a hydrogen fuel cell hybrid tug, as well as a recently completed three year project that monitored a conventional ASD Tug 2810 operating in the port of Rotterdam to see what was possible in terms of emissions and fuel cuts. It was from this project and looking at various cleaner burner fuel alternatives that the Hybrid tug was created.
“In the past many green solutions were simply too expensive for the tugboat market,” said Erik van Schaik, Design & Proposal Engineer, Damen Tugs, in a statement. “We were very mindful that this vessel had to cut fuel and emissions, but at the same time it had to be positioned at an attractive price for the market. We wanted to make being green commercially attractive too.”