Mv Harvest Frost — Photo credit: MHI
Mitsubishi Heavy Industries has announced the delivery of the first of three post-panamax bulk carriers to achieve energy efficient operations through the use of an air bubble lubrication system.
The recently delivered bulk carrier, MV Harvest Frost, is the first vessel of its size to use MHI’s proprietary Mitsubishi Air Lubrication System (MALS), which reduces the drag between the vessel hull and seawater by blowing air bubbles produced at the vessel bottom. MHI says that use of the system has been proven to help Harvest Frost achieve a 27% reduction in CO2 emissions compared to conventional bulk carriers, exceeding the target figure of 25%…
The MALS system uses special blowers to blow air from the vessel’s bottom, producing small air bubbles that cover the bottom of the hull like an “air-carpet,” reducing friction between the hull and seawater during navigation. The system was developed by MHI with support from ClassNK, and has already been adopted in module carriers, ferries and other ships constructed by MHI, the company says.
Harvest Frost also features a new bow shape designed to reduce resistance, while shallow draught facilities help the MALS achieve its target energy savings. For propulsion, an innovative system is adopted that effectively converts the main engine power into propulsion power by positioning fins forward of the propellers and placing special grooves in the propeller boss cap, according to MHI.
As much as I search and read about energy improvements in transportation, I admit this is the first I’ve heard of this system. Obviously it’s moved through pilot testing to production. This is one of the largest vessels utilizing the system.
I’m impressed. Significant savings from one of the least fuel efficient transportation modes around.
Eideard 
I’m curious how you conclude that ocean-born bulk carriers are “one of the least fuel efficient transportation modes.”
What do you mean by that?
While many of the advances in fossil fuel engine efficiencies have been scaled up – including those used in smaller oceangoing vessels up to ~2500 liters displacement – not much of that has been passed along to the truly large engines in freight-carrying vessels. I may not be completely up-to-date on that – and I know who to ask. But, just perusing transportation in general on a daily basis, I haven’t noticed any advances in that scale.
Here’s an interesting test bed – but advances are slower to roll out in bulk carriers than locomotives: http://www.greenship.org 🙂
I think you are muddling the topic a bit. As a solid goods transportation system, nothing is more efficient in terms of emissions or $ per ton-mile than large ships moving slowly over the planet. The next most efficient system is rail.
As far as engines themselves go, are you discounting the major advancements in cross-head 2-cycles starting decades ago? By the late 90s, the Electronic versions of the B&W designs were already going strong. (Valve control divorced from main crankshaft. No mechanical connection.)
Large engines are different but not somehow lagging in advancements. There are different scale effects too. What your little SuBaRu does is not the same as what your Giant B&W or Sulzer does…
http://marine.man.eu/two-stroke/low-speed-technology
http://www.wartsila.com/en/engines/low-speed-engines/rt-flex96c
They’re still relying on 2-stroke engines. Something rail has gotten away from. Voluntary or not, it’s produced cleaner, powerful engines.
Actually, once again, not true.
Low Speed Diesels are considerably more thermally efficient than Medium Speed. 4 stroke are not superior to 2-stroke for all applications–including rail. EMD 2-strokes make up a sizeable proportion of U.S. rail power and have much better throttle response than the GE 4 strokes. (Now that GE has bought EMD we’ll see what happens). As far as emissions go, again, 4 stroke is not an automatic advantage. As we move into Tier IV requirements for Medium Speed applications, even the 4 stroke designs require new technologies to meed both NOx and Particulate targets. In the case of 2-stroke there is a workable solution using urea. The Principle difference between 2 and 4 for emissions has to do with the scavenging function on 2 strokes. The EGR of 4 strokes is not directly applicable for obvious reasons.
Why not huge 4-strokes? Well, there are perfectly reasonable technical reasons for that. I’ll leave it for you to think about and research 🙂
If you’d like to see handy charts, go here:
Click to access tech_paper_low_speed.pdf
My tendency remains looking forward – which is the sort of tech I’ve blogged about for years. Either here at my personal blog or elsewhere. My fave in the field has always been Cummins – and they already have 4-stroke Tier 4 goodies available for clients like Siemens.
Cummins makes some POS little high speed diesels. You really aren’t looking at the same thing at all at larger sizes. Do some reading on how diesels really work and you’ll understand what I’m talking about. But you are down in the 500 kW size range with Cummins.They only serve the high speed diesel market. I specified QSK-19M in a 21 meter ferry. Worked fine (probably better than some of the MAN crap available at the time) but you cannot judge the technology of 80 MW engines from your interest in little high speed jobs!
There isn’t anything looking “backward” (as opposed to “fwd” as you imply) in crosshead 2 cycle technology. As I pointed out, electronic control continues to develop on crossheads, as does emission controls. I think you may also be unaware that 4 cycles have a fundamental limitation and problem with emissions. In order to reduce NOx to acceptable levels, 4 strokes have had to reduce BMEP, which reduces efficiency, while also driving up particulates. The EGR as well as some other ideas are deployed to deal with that. On the other hand, 2-strokes do not suffer the same way–they have better NOx starting positions but cannot EGR so need urea SCR systems to scrub the particulates as well as additional NOx.
We haven’t discussed one of my favorite albiet underutilized (not new!) ideas: fuel emulsification. This makes it possible to keep the BMEP high and still reduce the particulates by addressing the combustion directly. Fog is another tool but especially in reduction of NOx.
I’ve been involved in a few fog systems for fixed gas turbine installations.
I’ll forward your analysis to Siemens. 🙂
AND – things progressed well in the UEFA Europa League, this afternoon [MST]: Everton 3 – 0 Lille. Go, Toffees!
Nice about the Toffees, anyway. I don’t like anything bigger than a canoe.
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