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Post by yvr on Dec 29, 2008 23:03:14 GMT -8
"Electro" you've provided a valuable piece of technical information.
On April 26, 2008 BCF's Bruce Patterson a P Eng (professional engineer), and Andrew Martin an Eng'g Superintendent were patting themselves on the back over the Super C's. In fact they're so proud of the Super C's, they produced a positive spin paper for the Society of Naval Architects.
History has shown the German built vessels have vibration /noise problems. As well, fuel inefficiencies dictate they sit at the dock while 30 year old ferries with lower fuel burn rates operate the route on weekdays.
If Bruce and Andrew's presentation was held today it would have to incorporate the short comings discovered during vessel operation. With the problems the ferries have, it's doubtful the two gents would even produce the paper. As the Super C's appear to be an expensive and embarrassing scenario for BCF.
YVR
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Post by Dane on Dec 29, 2008 23:27:11 GMT -8
History has shown? We're not even done year one! In fact it was only 6 months and 11 days ago that the Coastal Celebration even got to BC, with the Inspiration starting service 7 days earlier. I am curious, regarding the vibration issues, have you sailed on a Coastal? Where were your particular areas of concern? Is there an area of the vessel you felt had vibration levels nearing another vessel in the fleet. Moreover, there has never been a major vessel added to the fleet that burned less than the vessel it replaced. We can argue all we want about the optics of BC Ferries "more fuel efficient" claims, but at the end of the day the vessel has to move its weight through the water, and to do this the Coastals are more efficient. The choice of a larger, heavier vessel, at a time when fuel was "cheap" is not a characteristic of the vessel itself...
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Post by Hardy on Dec 31, 2008 3:11:43 GMT -8
Dane: I agree with all parts of your post (IE: let time tell, it is still EARLY in the Coastal's in-service life) EXCEPT: The choice of a larger, heavier vessel, at a time when fuel was "cheap" is not a characteristic of the vessel itself... Actually, it IS quire specifically a characteristic of the vessel -- the MASS (displacement) of the Coastals WAS most definately a design characteristic -- therefore, the litres per tonne per nautical mile were MOST ASSUREDLY a calculation that would have been done.
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Post by cobblehillian on Dec 31, 2008 9:28:03 GMT -8
I wonder if calculations and specs for the Super C's included fuel burned per AEQ per mile. It appears from the Marine Atlantic press releases that they did these calculations as part of the evaluation and shortlisting of potential charter vessels. Marine Atlantic says their newly chartered vessel achieved a 34% reduction in fuel per AEQ mile over other ships in their fleet.
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Post by Hardy on Dec 31, 2008 15:08:10 GMT -8
While "per AEQ" stats tell part of the story, you also have to factor in (as has already been stated) that the Coastals were an upgrade in facilities/amenities over the V-class as well. Things like a fancy shiny new cafeteria come at a cost -- space, mass (displacement) etc. Computer work kiosks and upgraded wiring/cabling etc also takes up space and increases mass. So even if you went 1-for-1 on AEQs on the replacement vessel, there's a good chance that it may not be as "cheap" to operate as the one it replaces.
I know we've been over this forward and backwards, but somehow these inescapable truths seem to be trampled by the wayside every so often.
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Post by Dane on Dec 31, 2008 20:06:43 GMT -8
Calculation as per its success....
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rt1commuter
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Post by rt1commuter on Jan 1, 2009 16:17:28 GMT -8
Publications such as the Tyee, Monday Magazine and others have a pretty clear bias against the Liberal government. They'll latch onto any mistake the Libs make, true or not. While it's unfortunate that these ferries didn't come out as fuel efficient as we hoped, they were not a waste of money by any stretch of the imagination. They'll be providing service on the coast for 40 years, easy. They've already been proven perfect for route 30, and they seem to be working out fine on rt 1 as well (they ARE more fuel efficient than the Spooks after all! Faster too ).
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Post by lpoole on Jan 2, 2009 18:41:50 GMT -8
Note page 19
I overheard a chat with a CC crew member a few weeks ago who was asked about the fuel consumption issue - his response was that the CC is already more efficient than the Spirit class ships, in spite of the fact that the crew is very inefficient during turn-around, due to a lack of familiarity with the vessel. This inefficiency has resulted in a need to operate the vessel at a higher speed in order to keep to schedule. His assertion was that a lower service speed will be used once turn-around times are improved, with corresponding efficiency gains. A 20 knot service speed can be maintained using only 3 prime movers, resulting in a fuel savings of 650 l/hr. It seems to me, that this could easily make up the fuel consumption difference between the C class ships, and the much heavier Coastals, especially when you consider that 21 knots is only 85% of the Maximum Continuous Rating. The possibility certainly exists that the ships could, in the aforementioned scenario, be running faster than the specified 21 knot service speed. I'm curious to know what the mean service speed for the C class ships is.
During my voyage I wandered around the CC to investigate the vibration issue, and found that the vibration was most noticeable as close to the 'stern' as possible; in my case, sitting in a rear window seat of the cafeteria. I would say that the vibration is easily 1/4 of say, the Chilliwack, or the Tsawassen/Sidney while reversing. The vibration is not particularly noticeable anywhere else in the vessel in my opinion; I really think that it is just another minor issue for the concern trolls to whine about.
I will say though, that I was not as impressed as I had hoped with the ships - they feel too compartmentalized for my liking.
-L
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Post by oceaneer77 on Jan 5, 2009 22:58:28 GMT -8
So i did my first trip on one of the new ships.. and i must say that they are very well built and will last a long time. the steel work and welds are much better than the spirits. (the spirit are very good) The wiring/ electrical and pipework was all excellent.
The vibrations were not as bad as i had read... but were noticeable.. they seem to be a non issue when compared to the rest of the fleet!
So the only short coming in my books is the fuel burn, which seems to be the specified amount under the build contract.,,
I will still argue with hardy about the fuel burn... If we put a real nice seat in your truck (designed by lazy boy) and maby king sized bed in your sleeper with a 50 inch plasma tv it would be cool but your truck still need to deliver widget A from location B to location C.. If it takes considerably more fuel to do it all of the extras area nice but a waste... new ships should be more efficient per AEQ. Can we not manage this small feat? we have computer design programs now that were not even a dream when the original "c" class vessels were designed. New materials that are stronger and lighter, new engines that should be more efficient.. "I know we've been over this forward and backwards, but somehow these inescapable truths seem to be trampled by the wayside every so often"
oceaneer77
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Post by electrotech on Jan 6, 2009 2:02:31 GMT -8
New materials that are stronger and lighter, new engines that should be more efficient.. "I know we've been over this forward and backwards, but somehow these inescapable truths seem to be trampled by the wayside every so often" oceaneer77 IMO, the compression-ignition internal combustion engine has been 99.8% refined. There aren't huge gains to be made. Are you aware of how much engine and exhaust heat is scavenged from the Coastals for other ship systems? In the marine industry, how much tradeoff are we seeing for efficiency vs. emissions? FWIW, the Cummins in the Dodge pickup grew from 5.9L to 6.7L - to compensate for the reduced power imposed by ULSD and stricter emissions regulations. Don't try to tell me it doesn't burn more fuel... Moreover, we are largely into ULSD fuel in North America. My understanding is the more rigorous refining process reduces the btu per volume. That is a blanket effect for all ships in the fleet, old or new; however, some of the older vessels are getting some intelligent fuel management controls, and thus making the older vessels more efficient again. There's no equation to suggest that a ship 30 years younger (i.e. C Class) should be 30% more efficient (for example).
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Nick
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Post by Nick on Jan 6, 2009 8:32:12 GMT -8
I don't think the marine industry uses the same diesel fuel as road applications. I believe BCF is still using the old Low Sulfur Diesel, since it's cheaper and easier on the engines. In diesel, the sulfur component acts as a lubricant. Taking that out can be detrimental to an older engine that hasn't been designed to run on ULSD.
I'm not very familiar with the "de-sulfurizing" process used in the refineries, but I heard that they have to run the fuel through the cycle about 4 times to remove the sulfur for ULSD, as opposed to one time for LSD. And yes, it does reduce the energy content of the fuel by around 15%.
None of this changes the nature of the internal combustion engine, which can only ever run at a maximum of 25% efficiency. Of 100L burned, only 25 of those litres go toward pushing the ship forward. This is something that cannot be changed, as it's in the design of the engine.
I agree that there is no reason these ships should be so much more efficient than the older ones. It was BCF's mistake to promote these ships as being so energy efficient. When they say that they will burn 30% less fuel, as they did, people think of that in absolute terms, like per AEQ. Nobody thinks about that as per GT. That was a deliberate attempt by BCF to market something that wasn't there.
I'm not opposed to these new ships. I think they're great. People told BCF that they wanted more comfort and amenities on board the ships, so that's what they did. Nobody can deny that being on a Coastal with a full load of 1600 people is a lot more comfortable than being on a C with a full load of 1300 people.
Another way to look at it is to compare the ships to cars. Yes, if you're doing a road trip from Vancouver to Calgary, it's more efficient to transport five people using a Honda Civic. The car will do it without a problem, and you'll burn very little fuel. But, it would be a lot more comfortable to take a Chevy Tahoe. You have room to stretch out, more space for gear, more power for passing on hills, all of which would make the trip more enjoyable.
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rt1commuter
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Post by rt1commuter on Jan 6, 2009 12:29:58 GMT -8
Your efficiency number is too low. A good, modern diesel engine can operate at a constant efficiency of 35-40% and have a peak efficiency very near 50%. [ en.wikipedia.org/wiki/Diesel_engine]
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Post by Northern Exploration on Jan 6, 2009 12:56:59 GMT -8
I was in a BMW X5 with the 3.5? litre diesel engine with bluetech yesterday. Wow. The low end torque was amazing. The engine was quiet, not smokey, and very smooth. I am in love . Does anyone know if similar technology has made it into the marine industry? I believe I read about a clean burning diesel on a yacht - maybe it was one of Paul Allen's Yachts which are no money spared, as environmentally neutral as possible. I know the last time this discussion came up Hardy explained the big impact lower sulpher gas was having on truck maintenance. Does anyone know if Bluetech as the a similar effect on the longevity of a diesel?
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Post by Nick on Jan 6, 2009 13:10:31 GMT -8
Yes, thermal, or theoretical efficiencies are higher in general than what I quoted for a diesel, however there are numerous other factors that are not taken into account. Friction throughout the engine takes a huge amount of energy, which is compounded further by the lack of lubricity in ULSD. Granted, ULSD's not a huge issue for marine diesels YET, but it's coming.
More what I was trying to illustrate, is that the efficiency of a diesel engine has not improved much over the past 30-40 years. Yes, there have been some improvements with new valve arrangements, variable valve timing, electronic fuel management etc, but these haven't made a huge difference. The fundamental design of the engine has remained unchanged for over 100 years.
Find me an engine that will operate in real life at anywhere close to 50% efficient, and I will eat a very hearty helping of crow. Oil/gas/coal/nuclear fired steam power plants use a turbine Rankine heat cycle because it is more efficient than any reciprocating engine, and they can only just barely hit 50%, and that is with multiple regeneration cycles.
*EDIT to address Northern Exploration's post* I'm not familiar with the bluetech diesel, so I can't comment on that.
I know a lot of people are very surprised when they get into a diesel car or truck, because of the huge distances manufacturers have come with regard to smoke and emissions control (please understand there is a huge difference between efficiency and emissions). Gone are the days of a huge cloud of black smoke at startup and heavy acceleration. Diesel pick-up sales have skyrocketed in recent years because a lot of the headaches that used to be associated with diesel engines have disappeared. Now, they have more power, more torque, and get better fuel economy than their gasoline counterparts.
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Post by oceaneer77 on Jan 6, 2009 19:21:24 GMT -8
Hi Nick
You need to do more research.. On the thermal efficiencies..
" The Wartsila-Sulzer RTA96-C turbocharged two-stroke diesel engine is the most powerful and most efficient prime-mover in the world today. The Aioi Works of Japan's Diesel United, Ltd built the first engines and is where some of these pictures were taken.
It is available in 6 through 14 cylinder versions, all are inline engines. These engines were designed primarily for very large container ships. Ship owners like a single engine/single propeller design and the new generation of larger container ships needed a bigger engine to propel them.
The cylinder bore is just under 38" and the stroke is just over 98". Each cylinder displaces 111,143 cubic inches (1820 liters) and produces 7780 horsepower. Total displacement comes out to 1,556,002 cubic inches (25,480 liters) for the fourteen cylinder version. Some facts on the 14 cylinder version: Total engine weight: 2300 tons (The crankshaft alone weighs 300 tons.) Length: 89 feet Height: 44 feet Maximum power: 108,920 hp at 102 rpm Maximum torque: 5,608,312 lb/ft at 102rpm
Fuel consumption at maximum power is 0.278 lbs per hp per hour (Brake Specific Fuel Consumption). Fuel consumption at maximum economy is 0.260 lbs/hp/hour. At maximum economy the engine exceeds 50% thermal efficiency. That is, more than 50% of the energy in the fuel in converted to motion."
so engines are improving.. but slowly.. My point was that we should be seeing higher efficiencies. We have so many new technoligis that can if used properly make a new ship more efficent. But for some reason BCFC insists on buliding less efficient ships.
the explanation in comparing a suv to a commuter car is in some ways correct but still missing the point. Fuel prices are only going to increase, how did that big suv look last summer?
On The ULSD.. ultra low sulpher is not yet required. But low sulpher fuel is mandated but the IMO to which Canada is a signatory.
Nick your last post confused me "Now, they have more power, more torque, and get better fuel economy than their gasoline counterparts." did you not state before that they are unchanged in 30-40 years??
Remeber that i am a marine engineer.. But i am constantly shocked that the vessels from the 1930-40S are way more efficient (for the most part) than the floating econo boxes that we build now.
oceaneer77
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Post by Northern Exploration on Jan 6, 2009 19:22:31 GMT -8
The Bluetec diesels all use the addition of urea (called Adblue)that helps remove emission particulate. There is a tank that gets filled when you service your car - you don't self fill. (I wonder if this is an inducement to get you to bring your car to the dealer.) It lasts a couple of months. Mercedes developed it and is letting Audi, VW and Chrysler use the technology.
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Post by DENelson83 on Jan 6, 2009 20:14:03 GMT -8
The Bluetec diesels all use the addition of urea (called Adblue)that helps remove emission particulate. There is a tank that gets filled when you service your car - you don't self fill. Because what comes out of you is only 5% urea, compared to 32.5% urea in Adblue.
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Nick
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Post by Nick on Jan 6, 2009 23:33:10 GMT -8
I was comparing gasoline engines to diesel engines. Diesel engines have always gotten better mileage than gasoline engines. The gap has narrowed recently though, because manufacturers are making their diesel engines more powerful by increasing the amount of fuel they consume. For example, Ford's Powerstroke V8 diesel made about 190 HP in 1998 and regularly got over 22 MPG, whereas the 2008 makes 360 HP and is lucky to get 16-18 MPG.
When I said that they haven't been changed in 30-40 years, I was referring to the general design. Obviously there have been refinements, such as common rail injection, electronic valve control and other things, but the fundamental design of the diesel engine remains unchanged.
As far as that 50% Wartsila diesel goes, that doesn't seem right to me. Taking the peak power produced, and comparing that with the most economical fuel draw? Since when does the most economical fuel draw happen when the engine is producing the most power?
And I totally agree with you, we need a serious investment in new propulsion technology. That is what I have been trying to say all along. The concept of the internal combustion engine is obsolete and needs to be replaced.
I don't think you can really compare most of the older ships to modern ones, just because the performance characteristics are completely different. The newer ships accelerate much faster, often have higher top speeds, have more passenger space, and have more redundancies built in. Horsepower ain't free, so all these features have to come from somewhere.
And Oceaneer, I really appreciate your participation in this discussion. I am a 3rd year mechanical engineering student, and learn a lot from discussions such as this one.
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Post by electrotech on Jan 7, 2009 0:10:38 GMT -8
One thing that may be missed in all this is the engine loading. Marine engines see more load more of the time... not like a vehicle which has a multiple speed transmission. Those impressive MPG specs are obtained from a specific loading (i.e. relatively low) on zero grade, at a certain vehicle speed. That can't be compared to a prop that's moving against a 'full load' of water. Also, while a diesel idles quite efficiently - our ferries are clutched in, above idle, and pushing the dock for the duration of loading & unloading traffic. Can anyone confirm the fuel grade being used? I've tried to source non-ULSD for my uh.... 'furnace' or offroad equipment ( )and can't get it. Even good ol' #2 (albeit ULSD) is next to impossible to get this time of year.
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D'Elete BC in NJ
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Post by D'Elete BC in NJ on Jan 7, 2009 5:01:47 GMT -8
As far as that 50% Wartsila diesel goes, that doesn't seem right to me. Taking the peak power produced, and comparing that with the most economical fuel draw? Since when does the most economical fuel draw happen when the engine is producing the most power? And Oceaneer, I really appreciate your participation in this discussion. I am a 3rd year mechanical engineering student, and learn a lot from discussions such as this one. lol...can I add here that I'm a physics grad, and have spent way too many hours arguing thermo-mechanical conversion efficiencies both in and out of the academic world? Anybody want to talk about opto-thermal or opto-electrical conversion efficiencies instead? ;D Nick, to answer your question above as best I can, maximum efficiency usually occurs right around the torque peak rpm of the engine. It's not so much a matter of lowest fuel consumption, but of most effective use of the fuel...i.e. the most economical fuel draw. We see the use of constant speed props both in ships and airplanes more and more to maintain a constant engine RPM at this torque peak in order to take advantage of the maximum efficiency of the engine. I also think some clarification between BHP and SHP (or Effective HP) needs to be made. Brake horsepower (BHP) is measured at the crankshaft, and no transmission frictional losses are included. Shaft horsepower (SHP) is measured at the end of the drive-line, but doesn't include slippage losses associated with the propeller. Effective horsepower is the actual power available to propel a vessel inclusive of all losses. Measuring Horse PowerI make this point because Nick on several occasions made reference to efficiency which I interpret as referring to SHP, or effective HP, while everyone else is referring to efficiency related to BHP...apples and oranges, in my eyes.
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Post by Northern Exploration on Jan 7, 2009 8:36:03 GMT -8
I make this point because Nick on several occasions made reference to efficiency which I interpret as referring to SHP, or effective HP, while everyone else is referring to efficiency related to BHP...apples and oranges, in my eyes. Take the apples and oranges out of your eyes and make fruit salad and all will be well. You are far past me as my Engineer to English conversion program has crashed . I am sure my smart@ss comment will result in 5,000 technical pages of explanation sent to me .
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Post by Northern Exploration on Jan 7, 2009 8:59:08 GMT -8
Good uptake, I was waiting for someone to say it ;D.
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Post by oceaneer77 on Jan 7, 2009 11:38:52 GMT -8
Hi Nick
Thanks for keeping this interesting discussion alive.. and good to here from BC in NJ. I agree on the BHP to SHP statement. some BHP factors do not even include the pumps need to keep the engine running (small engines, as large ones have electrical pumps)
On a new note (this should be moved.. i will do so later) the EEStor ultra capacitor are nearing full implementation.. it is quite interesting and i hope that this new tech does work.
oceaneer77
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Post by Ferryman on Jan 11, 2009 22:47:15 GMT -8
Despite media reports, they still continue to have these ads posted at Tsawwassen. They save 7,000,000 litres of fuel compared to what? The New West? It's too bad BCF had to shoot themselves in the foot with their marketing of these ships. They probably should have waited until they were in service before they started posting adds about fuel consumption. I'm a strong believer that they're going to work just fine for years to come with BCF. Perhaps they thought they would same millions of litres of fuel, when they noticed the "mileage" they were getting during the trans Atlantic Voyage. D'uh, of course you're going to get some good "mileage" on a nice straight trip when you don't have to stop and go so much all day just like every ferry out there does. Just for fun, a few more AWESOME ads.
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Post by kerryssi on Jan 12, 2009 10:27:59 GMT -8
As time goes by I think you will see more problems leak out about the new ships (pun intended).
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