The trend to use dual-fuel propulsion is gaining momentum within the container ship sector
The adoption of dual-fuel engines has gained momentum and it is now possible to retrofit diesel engines to gas dual fuel, says Ole Grøne, MAN Diesel & Turbo’s senior vice president of low speed sales and promotions
Indeed, the existing MAN B&W 8L48/60B engine on Wessels Reederei’s 1,036 teu Wes Amelie is being converted into a 8L51/60 dual fuel engine in what is the world’s first conversion of a container feeder ship to dual fuel propulsion.
The trend for using dual-fuel engines is particularly evident in the USA. MAN Diesel & Turbo has won a clutch of orders from ship operators based there, including TOTE’s two new container ships that are already in service with 8L70ME-GI engines, two being built for Crowley Maritime with 8S70ME-GI engines, and two plus two 3,600 teu vessels being built for Matson Navigation Co. The first two for Matson will use MAN B&W 7S90ME-GI dual-fuel engines with seven cylinders and the next two will use 6G90ME-GI-EGR engines, each with six cylinders and exhaust gas recirculation for the control of NOx emissions.
Mr Grøne said: “Our solution was chosen because of the high efficiency and reliability of the two-stroke engine, combined with the fact that North America was the first area to introduce low sulphur restrictions and that gas is relatively low cost there. The option to operate on gas with high efficiency was a perfect match for our ME-GI engine.”
“In the coming years we may see more retrofits, as a result of stricter restrictions on emissions, including the 2020 sulphur limit. All engines in our contemporary ME engine programme can be ordered as a dual-fuel engine from the outset or be converted to burn gas dual fuel at a later stage without any special preparation,” Mr Grøne said.
With regard to retrofitting dual-fuel engines in place of conventional engines, he said: “We have been advising shipowners not to make any hasty decisions. If they do want to reserve the option to retrofit their engines, they need to consider the space that is needed for the gas tanks and establish the best time to carry this out. This might be at the time of the first docking, as it is a relatively big and, because of the cost of the tanks, an expensive job.”
With regard to the conversion of dual-fuel engines, he commented: “We have had discussions about vessels of all sizes, all the way down to 1,000 teu container ships.” He said that some projects were in the pipeline but had not yet been confirmed.
“Some ship operators are waiting to see the outcome of the 2020 global cap on the sulphur content of fuel. It all boils down to the price difference between gas, marine gas oil, heavy fuel oil and SOx scrubbers, as well as fuel and gas availability.”
Milestone for MAN engine set for OOCL newbuild
MAN Diesel & Turbo licensee Doosan Engine Co held a ceremony in Changwon, South Korea to celebrate the production of 100 million two-stroke brake horsepower. The milestone was achieved with the successful test operation of an MAN B&W 11G95ME-C (103,000hp) engine, the world’s most powerful engine type per cylinder and the most powerful engine in MAN Diesel & Turbo’s engine manufacturing portfolio.
The engine is bound for installation aboard a 21,000 teu container ship being built for Orient Overseas Container Line (OOCL) by Samsung Heavy Industries.
Ole Grøne, MAN Diesel & Turbo’s senior vice president of low speed sales and promotions, commented: “100 million horsepower is an achievement that until now, has only been reached by Hyundai.”
Speaking of its suitability for the OOCL newbuild, he said: “The bigger the container ship, the bigger the engine needed. Using an engine of this kind is the best choice, for the combination of power and propeller revolutions that it offers, which provide the most economical system at the lowest possible fuel consumption.”
He said the engine had been used in a number of ultra large container ships. The first to deploy it was Mediterranean Shipping Co (MSC), in a ship of a similar size to OOCL’s.