In a Riviera webinar dedicated to engine design and operational choices for emissions regulation compliance, nearly four of every five viewers reported having had engine issues since the inception of IMO’s sulphur cap on 1 January 2020
Part of Riviera’s Marine Propulsion webinar week, the webinar saw Delta Corp Shipping senior vice president shipmanagement Caroline Huot, ExxonMobil global marine equipment builder manager Steve Walker, MAN Energy Solutions director new technologies Kjeld Aabo and WinGD global sales director Volkmar Galke tackle engine options from cost, compliance and operational perspectives.
Engine options available to owners are extensive, and Mr Aabo listed a few in his presentation, noting engine manufacturers are simply trying to be prepared to deliver technology based on what regulations require and what the market determines.
“Our engine portfolio goes from 3 MW to 83 MW and it is based on different opportunities and technologies for the future,” he said. “We are not the ones to dictate what fuels will be the future fuels, but we will provide the technologies so it is possible to choose from them.”
Regarding the emergence of new fuels and regulations requiring emissions cuts, Mr Aabo also discussed his company’s commitment to retrofitting technologies on existing vessels as needed, a process he said MAN expects to see more of in the future.
“We also believe that, for many years, it will not be one fuel, it will be many different fuels that will be [used],” he said.
Engine technology is currently available or work is underway for diesel and Otto engine processes dealing with fuels that include methane, ethane, ethanol and LPG at MAN, and, Mr Aabo said the company has a roadmap for ammonia in place, as well.
“The first quarter of 2024, we will have an ammonia-burning engine on our testbed… and ready to go to the yard,” he said.
While the broad array of potential fuels for use in the fight to curb maritime emissions has engine manufacturers working hard to develop an equally broad array of marine engine technologies, the issue of choice – or lack of clarity in regulations – leaves many shipowners and managers in a troubling bind, as Ms Huot discussed.
She said, based on whole life cycle analysis of shipowner assets – the vessels in their fleet – owners face two equally difficult cost-benefit analyses: whether retrofitting existing vessels would make financial sense and what fuel-engine technology combination to invest in for newbuildings.
“Is retrofit really a solution? Is it accessible to these vessels, which are too young to be scrapped, but too old to be converted?” she said. “I think as an owner, you will have to ask yourself [this question], and it is as big a question as: what will I do with my next newbuilding?”
Regarding technology for newbuildings, Ms Huot said “if you have five fuels or five potential fuel alternatives to choose from, it is like having none. Right now, the choice is nearly impossible. We could say LNG is a transition fuel. But the deadline and the lifespan of the ship does not offer much flexibility.”
Asked which fuel would be the dominant choice for merchant ships until 2025, 42% of respondents chose LNG, 39% chose very low sulphur fuel oil (VLSFO), 9% chose heavy fuel oils (HFO), 5% chose methanol (bio), 3% chose hydrogen (drop-in) and 2% chose ammonia.
Some 93% of respondents felt the consumer would ultimately feel the cost impacts of capex and opex spent to equip vessels to use alternative fuels, with only 7% disagreeing.
And in terms of technology choices, nearly 90% of respondents felt that flexible, dual-cycle engines supporting gas and liquid fuels were the safer investments, with 11% saying a mono-cycle engine was the way to go.
Adding the research and development perspective to the dialogue, Mr Galke responded to Ms Huot’s points on market complexity, pointing to flexibility as a shipowner or operator’s best bet.
“You need to have a flexible platform,” he said. “Having two cycles in one engine, the Otto cycle and the diesel cycle, so you have the flexibility to have either gaseous fuels in the engines or liquid fuels in the engine, whatever liquid fuel or whatever gaseous fuel will come in the future.”
Both Mr Galke and Mr Aabo acknowledged that, in any retrofitting, work will need to be done on fuel injection systems and both said the point should be taken into account given the likelihood for an increase in retrofits in the future.
Covering lubricants, Mr Walker said that as engines evolve to meet regulatory requirements and market decisions, it is imperative that OEMs and lubricant manufacturers collaborate to ensure that appropriate lubricant products that work for a diversified engine market are available when vessels hit the water.
“As the engine evolves, the lubricant has to evolve in step with it. That is where joint research and development with the engine builders is critical,” he said.
“We need to know what their next steps are from a temperature and pressure perspective so that we can have the right lubricants available for when engine number one hits the seas.”
In terms of current challenges, Mr Walker said IMO’s global cap on sulphur in marine fuels had marked a sea change in lubricant needs.
“In January this year, we took all the sulphur out of the fuel, or most of it,” he said. “And the focus now is less important on acid neutralisation.”
We are moving into a regime where deposit control, detergency, the sort of oxidation stability [and] ability of the oil to deal with higher temperatures and wear protection on these newer engines where the pressures are higher puts the liner interfaces under more stress. We need surface-active additives that provide a level of anti-wear performance,” he said.
Via a series of polls, attendees reported their own engine troubles since the onset of the sulphur cap that included ring breakage, scuffing and carbon deposits, with 78% reporting issues and only 22% reporting no issues at all since the sulphur cap has come into force.
The dominant issues reported when using new fuels was sludging or compatibility, with 40%; 21% of respondents said they suspected but had yet to define a problem; 14% reported combustion issues, 12% reported issues with cat fines, 8% reported fuels that did not meet the sulphur limit, and only 5% reported no issue at all.
In terms of cylinder lubrication for those using VLSFO to comply with the sulphur cap, 40% said they consistently use a 40 BN cylinder oil, 54% said they alternate between 40 BN and 70 or 100 BN and only 6% said they consistently use 70 BN, with no one consistently using 100 BN.
View the webinar’s full discussion, which includes recommendations on feed rate and BN numbers as well as plentiful discussion on the future fuels landscape.
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Panellists (left to right):