Oshima, the world’s largest builder of Open Hatch Bulk Carriers (OHBCs) – has released its conceptual design of a vessel promising 50% reduction in carbon dioxide (CO2) emissions.
The ECO-Ship 2020 has been developed to lower fuel costs, meet or exceed current and future regulatory standards, while improving commercial performance. It is to be noted that the concept has been developed in co-operation with DNV GL.
The main savings potential for the vessel, which will cost more to build than current designs, is said to come from cuts in fuel costs. Since the oil price is anticipated to rise continuously, the partners believe the extra cost spent on the ship can be recovered within a decade.
The projected cost savings have also assumed a future tax on CO2, Adam Larsson, project manager for DNV, said during a press conference at Nor-Shipping this Thursday.
“ECO-Ship is an innovative concept, but every feature is based on existing or emerging technologies,” Larsson said.
Features include a wide twin skeg hull, Oshima’s ‘Seaworthy’ bow, an air lubrication system, lean-burn four stroke medium speed gas engines from Rolls Royce and a waste heat recover system that can give a 5% fuel saving at normal cruising speed. It also has hatch covers made of composite material that weighs half as much as traditional steel covers.
Much of the 50% CO2 reduction is said to come from operating with a highly efficient liquefied natural gas (LNG) propulsion system.
“Any owner interested in saving on fuel and staying ahead of regulations should be interested in the concept ship,” Larsson added.
“Our objective is to be the first shipyard to deliver an LNG-powered bulk carrier,” said Oshima’s president Hiroshi Minami.
“To achieve our goal, we worked closely with DNV and other suppliers to develop a viable design concept. We are confident the results will exceed expectations.”
According to the partners, the space required for LNG fuel tanks have had a minimal impact on cargo space for the ECO-Ship design.
A new report has also shown that some current LNG-fuelled ships with dual fuel systems have a worse overall greenhouse gas (GHG) impact than conventional diesel engines, while lean-burn LNG ferries in Norway have a similar GHG profile as conventional ships due to leakage of methane from the LNG fuel systems.
According to Geir Bjorkeli, Vice President, Systems Sales & Marketing Campaigns Merchant Vessels at Rolls-Royce, their lean-burn engine has a minimal methane leakage.
Responding to a question, he said the engine emitted about 30% less CO2 than a comparable diesel engine.
He said that when adjusted for more the methane slip, converting the methane into CO2 equivalents, still meant the engine emitted at least 23% less CO2 than a diesel engine.