12 minute read
Poised for rebound
We have continued our success in the dual-fuel segment and ended the ‘‘ year with a 59% share of the dual-fuel market
engines. However, simple comparisons between the emissions from an Otto Cycle low-pressure X-DF engine and a high-pressure dual-fuel Diesel Cycle alternative can be misleading, Galke noted. “If you take into account the entire energy consumption from all of the machinery on the vessel, including the main engine, generators, pumps, electric motors, boilers and everything else, the emissions from the two systems, high pressure and low pressure, are equal.”
The market response to the X-DF 2.0 has been extremely positive, Galke noted, from ship owners, shipyards and the engine builder. “One of the reasons that the solution is so attractive to the market is that the next generation iCER design will allow for the removal of other equipment from the engine room.” The effect is to offer emissions reductions with lowest possible increase of CAPEX.
SHIPOWNER INTEREST
Looking ahead at the market in 2021, Galke noted that with the current market at such a low level, “it can only be better next year.”
Based on feedback from WinGD's sales network, Galke expects the global market to pick up slightly, adding that he did not expect it to go through the roof. “But it will not go down and it will not stagnate.”
Within that outlook, Galke noted that there are market segments where demand was likely to be resilient. Galke focused on the LNG carrier market, noting that a number of vessels were being ordered in connection with Total's Mozambique Project. The growth in this sector is anticipated to continue this year: a substantial number of slots have been reserved at Korean and Chinese yards for LNG carrier newbuilds in connection with the North Field Expansion (NFE) programme.
However, when asked about interest in LNG as a fuel from outside the LNG carrier sector, Galke noted that the market was slower than in early 2020. Neither container ships nor the bulker market were near a tipping point, where supportive economics might encourage the segment to switch fuel type.
Rather than focusing on vessel segments, an individual vessel's suitability for dual-fuel propulsion should be considered from an employment perspective. Regardless of the vessel type, whether its a bulker or a container vessel, vessels operating on long-term charters or liners are more likely to opt for an LNG engine than spot market vessels.
“If you have a long-term charter for exporting iron ore from Australia to China, you also know exactly where you can bunker as the same goes with boxship liners so that I would say these employment segments are where you will see faster movement on LNG than in others.”
Although the proportion of the global fleet operating on LNG remains quite small, Galke noted that he expected further growth.
“We think that we could see around 10% of the global orderbook fitted with dual-fuel engines quite soon.”
FUTURE DEVELOPMENTS
Galke concluded by noting that WinGD was focused on developing solutions to meet the demands of future technology coming into the market.
Among the newest areas for WinGD was the extension of its product range to include hybrid solutions which include shaft generators, batteries, and auxiliary engines as well as other energy sources. The solution, which is still being offered on a case by case basis to interested shipowners, offers an alternative approach to greenhouse gas emission reduction.
WinGD is continuing to act as the designer and the system integrator but is not planning to move into the hardware supplier space today.
“By placing the two-stroke engine at the heart of the vessel's energy configuration, you can look at the energy mix on board, and look at the equipment specifications and make recommendations about optimisation - whether that means specifying a main engine with fewer cylinders, or by reducing the number of gensets and introducing a battery pack and a smart power management system.”
That is one of the new technologies that WinGD will be exploring in 2021. "We are already in discussions with potential ship owners and ship yards," Galke concluded.
THE ROLE OF ALTERNATIVE FUELS
Galke noted that while battery hybridisation integrating shaft power solutions represented one approach to meeting IMO 2030 standards, the potential efficiencies offered by other solutions, such as waste heat recovery, were limited.
Leaving aside operational responses, such as speed reductions, Galke noted that the industry was approaching the technical limits of the efficiencies offered by other solutions. Technologies like air lubrication, as well as further hull form optimisation, offered benefits but would be insufficient to meet upcoming emission reduction targets.
“In order to meet the IMO 2030 and IMO 2050 targets, I don't think there is any alternative to future fuels.” However, Galke noted that none of the alternative fuels under consideration apart from LNG were currently commercially available on a large scale globally with the infrastructure and safety standards required.
8 The engine
designer is off ering hybrid solutions on a case-by-case basis. It is one of the new technologies that WinGD will explore in 2021
MAN ES ADDS THREE VERSIONS TO ME-C 10.6 PORTFOLIO
More details have emerged of three new low-speed engine variants from MAN Energy w-speed engine variants from MAN Energy Solutions - S50ME-C10.6, S60ME-C10.6 and G80ME-C10.6, reports Paul Guntond G80ME-C10.6, reports Paul Gunton
Initial details of these new engines were revealed via a ‘Market Update Note’ (MUN) issued by the company on 16 December, which reported that the new versions off er improved specifi c fuel oil consumption (SFOC) across their entire load range.
That note positioned these new 10.6 machines as complementing its G95ME-C10.6 engine, which was launched in February 2020, but Thomas Hansen, head of the two-stroke promotion and customer support team at MAN Energy Solutions, told The Motorship that it was “still very early” to release detailed technical specifications of these latest applications of its 10.6 generation.
But he said that the engines will be included in the next edition of MAN ES’s Marine Engine Programme, which will be released “during the first months of 2021”, according to the MUN. In that case, more technical data should be available shortly.
Meanwhile, material he provided to The Motorship included some specific details of the improvements made to the S50ME-C10.6, which include a new type of low force exhaust valve and a change to the material used for the exhaust valve spindle, both of which will reduce weight. A summary of that engine’s upgrade is in the box on this page.
Mr Hansen also provided more general information about the other two engines, which revealed that, in common with the G95ME-C10.6, both will be compatible with the Triton engine control platform that MAN Energy Solutions introduced last year eventually to replace its multi-purpose controller (MPC), which has been in use since 2003. Triton is a modular system, making it future-proof and compatible with such innovations as data exchanges, but it is arranged to be familiar to those already using the MPC.
SEQUENTIAL FUEL INJECTION
A key change to the earlier versions of these engines is that these 10.6 models will include sequential fuel injection - a technology that was pioneered for two-stroke engines on the G95ME-C10.6 - and exhaust gas bypass tuning, which will give them a new low-load tuning for optimising SFOC and for NOx emission compliance, the MUN noted.
Sequential fuel injection allows each fuel valve on a cylinder head to be controlled individually, which makes it possible to “achieve the best possible trade-off between SFOC and NOx formation,” Mr Hansen said during a customer webinar on 28 January.
They will not, however, be offered with sequential turbocharging, which is another innovation found on the larger engine design. Kjeld Aabo, MAN ES director of new technologies for two-stroke promotion and customer support, said during the webinar that although sequential turbocharging could theoretically be applied to these engines, a cost-benefit analysis persuaded the enginebuilder not to offer it for these smaller sizes.
For sequential turbocharging, one turbocharger of a smaller size than the others is fitted to an engine, with large engines having up to four turbochargers, Mr Hansen said. The smallest one would not in use at loads below about 65%70% of full load, making it possible to match an engine’s turbocharging to a broader load range. At low loads, this gives a smaller turbine area and a higher scavenging air pressure, giving “possibilities to optimise the SFOC without jeopardising any emissions regulations,” he said.
Asked whether sequential turbocharging could be retrofitted to these new engines, he said that the cost would be prohibitive: all their turbochargers would probably have to be replaced, along with upgrading the engine control system, piping and valves. In any case, sequential turbocharging can only be applied to engines with more than one turbocharger, which excludes the 50- and 60-bore versions of the new 10.6 platform, which are always equipped with a just one turbocharger.
This is an evolution, rather than a step-change in technology. “It is basically the same as turbocharger cut-out,” Mr Hansen said, although the process is automatically controlled by the engine control system. He credited this development not only on the experience it has gained from using turbocharger cut-out on many other engines, but also on input from its cooperation partners, ABB and Mitsubishi. The result, he said, is “a really clever system.”
January’s webinar was focused on future propulsion options for large and ultra large container vessels and concentrated primarily on the G95ME-C10.6 engine. The first unit is due to be delivered in Q1 of next year, Mr Hansen told The Motorship, but he declined to identify its destination yard or vessel, apart from confirming it would be within its target market of large container ships. It is one of 12 of these engines on order at the time of the webinar, when six more were on option.
70% of full load, making it possible to match an engine’s turbocharging to a broader load range. At low loads, this gives a smaller turbine area and a higher scavenging air ii “ ibiliti t ti i th SFOC ith t
S50ME-C10.6: MAIN UPGRADES
A number of changes have been made to create the 10.6 version, including: 5 New cylinder cover 5 New type of low force exhaust valve 5 Sequential fuel injection system 5 New hydraulic cylinder unit 5 Modified high pressure pipes for fuel valves 5 Modified hydraulic pipe for exhaust valve
8 To achieve To achieve
sequential fuel sequentialfuel injection, a control valve has been added to operate the fuel booster injection valve
SPIN DOCTORS: A NEW TAKE ON PEAK SHAVING
Energy storage solutions (ESS) are turning up onboard an ever-increasing range of vessels, but batteries are not the only, or even the most suitable, solution for peak shaving a supersized demand. Flywheels might do better, writes Stevie Knight
Boring into a seabed 3,000m below means the drawworks onboard a drillship - those sizeable winch systems controlling the drill lines - will be responsible for handling thousands of tonnes. But while active heave compensation (AHC) is key to keeping the drill head stationary, “each lift of the string asks a couple of megawatts of the generator load” explains Richard Verhoef of NOV.
An energy storage system could smooth out the power peaks and pick up the wasted kinetic energy - but the question is, what kind of ESS could handle not only the scale, but also the frequency of these cycles?
The more familiar solutions used in the industry weren't capable of meeting the demands. Firstly, “as a rough rule of thumb, a battery can only absorb around half of its energy capacity in one go”, says Verhoef. Secondly, even scaled to cope with this challenge, the work schedule of a drillship could result in a million AHC-driven cycles in a couple of years. “That's enough to destroy any battery,” he points out, and it would also likely kill a supercapacitor.
By contrast, there's nothing better than a flywheel if cycle life is the issue.
However, these are not merely big lumps of metal as there are huge forces to contend with: take the 1,500mm, 3.5 tonne flywheel developed by NOV and set it spinning at 2,000 rpm, and there will be tremendous stresses at its perimeter. Therefore, the manufacturing must be tightly managed.
But the mass is, after all, what makes it work. As Verhoef explains, NOV's flywheel “can absorb a lot of power - 1.75MW peak - and give out the same amount for around six to ten seconds”.
That may seem like a short period of time, but it has been tailored to tally with the length of demand from the active heave, “which is basically the wave period,” he points out. Admittedly, this differs a little from region to region and the response is affected by the vessel's shape, but he adds that “generally, it's around eight seconds.” This brevity also simplifies the technology by, for example, allowing the design to stick with spherical roller bearings instead of specialised magnetic varieties designed to 'spin out' the energy retention.
However, there are longer spans of demand such as when raising the drill bit. While it's theoretically possible to scale up the flywheel to meet these operations, it would entail an unfeasible rise in diameter and motor size.
Therefore, NOV has added a more conventional 450kWh lithium-ion battery system linked by two 1,100 hp motors to create the PowerBlade kinetic energy recovery system. The neat thing about this pairing is that the flywheel can push the power either back to the winch or to the battery where it also acts as a buffer, giving the cells an easier ride. The combination lends the PowerBlade a 3.25MW maximum charge absorption, while it can also belt out a sizeable 4.75MW at peak output.
It is effective: the theoretical figures from a Norwegian vessel show up to 80% energy recovery during active heave compensation. Further, as with other ESS, if incorporated at build, the technology allows resizing the power plant instead of scaling it for peak demand.
Most importantly, it promises to soften wear and tear for much of the onboard kit. “The endless ups and downs on the distribution bus aren't good for any of the components,” comments Verhoef. This gives you a more stable system.”
The PowerBlade is to be offered as a fully boxed solution in a standard ISO container that can be dropped onto the deck. “The installation philosophy is that it can be fitted between jobs with the pre-wiring carried out during operations and just a day or two allocated for putting this onboard while offshore - so the ship doesn't have to come into port,” says Verhoef.
OTHER APPLICATIONS
It will likely find a wider audience than the drillships. Guido Van den Bos, business development director for vessel designer GustoMSC, (a NOV subsidiary), has been considering other potential applications. For example, he sees advantages for “large jackups or other semi-submersible vessels.”
Photo: NOV 8 Flywheels can
pick up energy and return it endlessly, making them suitable for fast cycle, peak shaving applications
8 The PowerBlade
