Efficiency enhancement has traditionally been realised in the shipping industry through improved vessel and engine design.
As naval architecture has become increasingly productive with the advent of CAD-based design, parametrisation and improved simulation software, significant gains have been achieved through optimised hull shapes and lower resistance, to the extent that further gains are becoming increasingly difficult to come by on conventional vessel designs.
This problem is even more prevalent for engines, which have traditionally offered a reliable efficiency boost with each new generation of units. Engine manufacturers have begun to find that they are approaching ‘peak efficiency,’ a concept highlighted in January’s The Naval Architect (p.20) which noted that engines have largely reached their highest safe engine pressure ratio (between firing pressure and mean effective pressure). Ever-smaller single figure gains are thus becoming the norm, most of which now involve mechanical improvements such as friction reduction.
The result is that many efficiency-minded shipowners are now instead looking to improved hull coatings, waste heat recovery and alternative fuels such as LNG to stay ahead of the pack. However, as the majority of the world shipping fleet is outfitted to burn fuel oil, many owners are choosing not to switch, citing poor infrastructure, the high cost of converting vessels to burn LNG, and the inconvenient truth of methane slip throughout the supply chain.
It is these reluctant – or perhaps pragmatic – shipowners continuing to use fuel oil but seeking efficiency gains that German company FuelSave GmbH hopes to target. Founded in 2012, the company offers efficiency enhancement technologies ranging from waste heat recovery systems to green energy units for industries including road transport, land-based industry and shipping. Its main maritime offering is a 2017-patented hydrogen synthgas generator and injector, dubbed FS Marine+, which combines syngas injection with water and methanol injection to achieve cleaner, more complete and cooler combustion. This is claimed to reduce fuel consumption and thus CO2 emissions in analogue relation, as well as further reducing air pollutants including NOx, filter smoke number (FSN) and particulate matter (PM). Reduced engine wear and tear, and the requirement for less lube oil, are also cited as benefits.
The Naval Architect spoke to FuelSave co-founder Marc Sima about FS Marine+ during SMM, at which the company showcased a containerised version of the technology. Describing the system, Sima said: “Depending on the load profile and the engine, we’re injecting hydrogen, oxygen, water and methanol in different quantities and combinations depending on the effect that we would like to achieve.” This effect, Sima explains, relates to the degree of fuel savings versus emissions reduction: “There’s always a trade-off – you can dial in for higher fuel savings but then emissions may increase”. However, the system’s standard configuration is claimed to save between 10-15% in fuel consumption, reduce CO2 by 8-15% and FSN/PM by up to 40%. NOx reduction is more dependent on configuration, but falls between 30-80%.
To validate FS Marine+, FuelSave partnered with SAL Heavy Lift (now owned by Harren & Partner), engine service company Carl Baguhn Hamburg (CBH), and DNV GL – which has since certified the solution – conducting a three-year, 5,000-hour trial on heavy lift cargo vessel M/V Annette’s auxiliary, MDO-fuelled engine. The average reported fuel saving throughout the trial was 16%, with CBH service engineers noting far cleaner combustion. Particularly of note was the visible FSN reduction; Sima said that “the chief engineer went down into the engine room to check it was really running!” Following the successful performance, SAL Heavy Lift has since chosen to fit four more FS Marine+ units across its fleet, with the contracting process coming to an end last month.
With a verified saving above 15%, FS Marine+ therefore represents an attractive proposition. However, shipowners currently pre-occupied with decisions surrounding the 2020 sulphur cap are sure to recognise that, by itself, the system is unable to achieve compliance for vessels using fuel oil, as it only reduces sulphur analogously to the amount of fuel saved.
Where it can help, though, is by allowing a smaller scrubber to be installed. Sima picked up on this point at SMM: “Very often the problem is that you lack the space for a scrubber. In our case have emissions savings already, so the scrubber can be downsized – it can work less, using less energy. This means a better scrubber ROI.” This relationship works both ways, added Sima: “If you dial in more on the fuel efficiency side [using FS Marine+], the scrubber takes care of the emissions.”
Of course, installing both the FS Marine+ system and a scrubber will prove costly, despite the fuel savings the former generates. Depending on how this cost balances out against alternative fuels such as LNG, owners may be tempted to convert their vessels to gas operation to achieve compliance. For Sima, however, the case for LNG is diminished by its dubious environmental credentials: “No LNG ship has ever been built without high financing. It was thought to be greener, but now they’ve spent the money, done the studies and realised it is a disaster because of methane slip.” For Sima, fuel oil burned cleanly is therefore preferable to LNG, which some believe to be more polluting across its entire supply than conventional marine fuels due to the potency of methane; according to the Intergovernmental Panel on Climate Change (IPCC), its comparative impact over 100 years is 25 times worse than CO2.
The total impact on the climate of LNG use in shipping has yet to be fully accounted for, with the industry far from a consensus. What is certain is that the majority of shipowners are motivated by cost rather than environmental responsibility. As such, FuelSave hopes to encourage installation by offering FS Marine+ with a guaranteed ROI based upon each customer’s usage profile, coupled with a performance guarantee by which the warranty is extended following any system downtime. For shipowners less keen to commit, a leasing option is also being explored that will offer flexible payback depending on the amount of fuel saved, but always with a “positive cash flow for the customer.”
For shipowners sticking with fuel oil, rising prices are likely to provide a further incentive, particularly those with large, fuel hungry fleets. Sima relayed a conversation he’d had with Maersk, for example, which explained that its annual bill is US$8-15 billion depending on how much it charters, noting: “We already have a business case if they save 2%. That’s a US$160-300 million fuel saving.”
Many of the vessels chartered by the likes of Maersk feature two-stroke engines, which FuelSave is yet to work with. However, an FS Marine+ unit large enough to handle the demands of a two-stroke is currently under development according to Sima, as is a unit for four-stroke main engine use, financed by a €1.6 million grant from EASME (EU Executive Agency for SMEs).
It is likely that when FS Marine+ is used in conjunction with the engines of the ultra-large vessels fast becoming the backbone of seaborne trade, the most convincing case will be made regarding the to the benefit to both shipowners’ wallets and our shared environment.