Diesel Electric Propulsion

Not for nothing QMII is powered by a DE system as the engineers and designers that developed her forsee or have reckoned with the fact that we are in - probably - the last stage of the fossil fuel era. If not for quantitative oil shortage it might another, more pressing reason that might add more complexity to this global query: the increase of global temperature.

What can be in the long run an extra asset to the installation of DE propulsion is the fact that - next to all the other advantages of DE propulsion - any type of engine can be mounted to power the electric supply-system.

Whatever turns up as a second generation source of power, it always can be connected to the already existing electric propulsion system.

What will be next to the combustion engine is still a riddle - for the large yachts say, 50 meters plus - can be equipped with miniaturised nuclear powerplants that powers a small steamturbine that powers the generator that supplies the electric energy for the propulsion.

Unless another type of engine may see the light. What surprises me is that one still talks about ill feasible systems like solar energy and the lot. Solar energy might be capable to power little apliancies over unspecified distances, but the larger yachts with their small city demands of electrical power, will be the first victims when someting unforseen happens to the present oil-supply.

In such a case it will definately do no harm to install a DE system that has also other practical advantages: reduction in maintainance, reliability, reduction of noise, full torque at all speeds, increased fuel economy, keeping similar powerspecs to traditional applications.

Yes - certainly DE systems present that versatility as far as power plants are concerned in that the alternators can be turned by anything, as can hydraulic pumps for that matter!
I do believe that the world is steadily moving away from nuclear as a source, because of the 'dirty' connotations that come with it, but that would not preclude mega-yachts from being powered by a mini-reactor.
So what would the world be like with a hundred mini-reactors cruising around the oceans, running aground and having collisions with each other! The Greens will go bananas! Interesting, none the less.

And sure - solar is hardly worth the mention as a source.

What interests me more will be the construction material and methods of the mega-yachts of the future.

Wooden sailing ships will have their day again, surely?

This is a nice topic, because it leaves much to the imagination!
Woodge, in the very near future, if a shortfall of oilsupply happens all in a sudden, and the supermega's needs a bit more than "just an engine" to power up, then there might be no other choice - save for remaining in the harbour.

A small nuclear powerplant can be beautifully fitted in a machine room and the only problems to be found are those of the respective governments allowing third parties to buy the radioactive fuel.

Out of nuclear engineering and design's view, there are no real problems to such a conversion. There are enough technicians around that can handle such powerplants and the advantages are so substantial that it surprises me actually that nobody had already made earlier attempt to get such - I admit complex - configuration integrated in a supermega.

Your second topic/issue is absolutely justified/justifiable. The problem is however, that in general the existing shipyards are conservative and do not dare, generally speaking, to discuss this kind of issues with their prospect clients.

Proposing an unusual material might lead to a loss of client and therefore loss of business and international recognition.
In this respect I have to make an exclusion for two Dutch Shipyards, who had dared to proceed, or who were not afraid to tackle this issue.

I am writing this now and if they are reading this, they will know at what I am pointing at.

Seven years have been passed on and still no serious ship has been built from this material.

But where starts material-consciousness?
On the table of the Architect? Yes.
And then?
Shipyard? Up to a certain extend. They might be influential but they are not decisive.

The client then?

No. Just the individual who will say: "I would like to build a boat from that and that material." And suddenly all the architects and yards will pop up, eager to tackle such challence.

Of course, to back up my story, I can name man and horse, so to speak.

This is actually a forum for all, all supporters do have a certain commercial interest,
and the new material wil pop up sometime, somewhere.

Finally, new materials exist, but it needs a no. 1 that will make the decision to go onwards.

I am very interested to hear more about this material?? Please tell more?
You don't have to mention names even, just a description of the material?

I am very, very interested.............

To give you a reply is not the problem, Woodge.

I know that there is in the US somebody attempting to find customers for this material, to no prevail; probably he faces same difficulties as I did long time ago.

I haven't pursued this venture anymore, maybe I am tempted to do it again, although I am not anymore involved in yachtbuilding and more in the production of Naval vessels and their propulsion.

In terms of a superyacht say, over 50 meters or more, you'll save about 30% in gross weight of hull and superstructure material, in comparison to the steel/alu traditional concept.

I have no need to promote myself, or the company I work in, so I prefer the present state of the issue and that is obscurity. Let it simmer, it was published once in Boat International, long time ago and I got only one reply on that topic, from Tasmania, that took almost half a year to reach me.

If you are personally interested, you could contact me.

Article in the Miami Herald on Diesel Electric propulsion's fuel savings and merits...

http://www.miami.com/mld/miamiherald/sports/motorsports/12460242.htm

Rim-Driven Propulsers

The web master posted notice of some new technology at http://www.yachtforums.com/forums/news-products-and-launches/3823-rim-driven-prop.html but it didn't permit one to reply there.

So I thought this subject matter might well be integrated in this subject thread as it appears as though there are some number of new 'Peripheral Driven Prop' arrangements coming on line and/or being researched. These concepts lend themselves well to the electric driven concept.

I posted this message on another forum today,

"Exciting New EPS Thruster (& Propulsion)"

The results of the Design at METS awards, announced at this morning's Breakfast Briefing, appear to prove that the wheel can be reinvented according to the Jury, who named the EPS Silent Thruster from Van der Velden Marine Systems of the Netherlands as the overall winner.

This product redefines the bow thruster, eliminating the usual arrangement of a central hub and gearbox. It instead uses exchangeable blades that are connected to an outer ring; this floats on ceramic bearings and is powered by an integral motor in the casing. The solution is elegant, well designed, and promises a number of advantages over conventional concepts
_________________________
....from their website...

In addition to fixed thrusters they are now working on retractable systems as well as utilizing the concept of the EPS as a means of propulsion !!

I posted this as well, "Maybe the ceramic bearings aren't all of the technology that has allowed the emergence of this new propulser. It appears as though the preipheral drive power is an electric motor of some sort integrated into the outer ring. This would make sense with all of the new talk of diesel/electric systems."

....for more visit http://boatdesign.net/forums/showthread.php?p=65517#post65517

Diesel electric makes a lot of sense. I've been trying to get information on the actual reliability of the azipods with little success.
Anyone aware of an actual incident where an azipod has struck a solid object?

This is a very interesting thread, with lots of useful information. There can be no doubt that DE is the wave of the future. If you look to the cruise industry, which has been a "Pioneer" in the use of DE with pods on many of their new vessels, the only drawback has been the failure of seals in the pods, allowing seawater to come in contact with the drive motors. Several ships were actually pulled out of service in order to correct this issues. The advantages are clear, but the practical aspect is that there still are some drawbacks. I am all for it, but it clearly needs more R &D.

Thanks MacMcL

There do seem to be issues with the pods. Perhaps diesel electric systems using standard through hull shafted props is still the way to go at this time.

http://www.ebearing.com/news2004/092101.htm

Passage Maker Magazine recently did an article on a DE retro fit to a smaller vessel (40'or 50") using motors to turn the props as opposed to pods. Quite interesting, and they intend to follow up with future coverage. Seimens seems to be the leader in providing the equipment right now.

Motor Sealing and Bearing Failure

Thanks Godger

Those bearing failure references were interesting, but lacked some details. The reports stated that there were 2.5 foot dia bearings that support the shafts, but failed to mention the trust bearing sizes or types, even while it stated, "The bearings are apparently failing under thrust loading."

I find it somewhat difficult to understand that the peripheral bearings would fail under thrust loading. I find it much more likely that the thrust bearings would fail, as they are being asked to absorb both forward and rearward thrust loads. Possible the 'lips' of the peripheral bearings are being used to absorb the thrust loads, and these are too small in total area as a design effort to keep the overall diameter of the pod to a minimum. But even this doesn't make sense as the motor unit is already a bigger diameter itself.

Note that these podded designs house an electric motor that must be sealed against the sea water, as well as the likely hi-capacity bearing lubrication medium. The electric motors of the newer generation 'peripheral drives' is a permanent-magnet DC unit that is not being isolated from the sea water, nor are its bearings.

Azipod propulsion

Hi all,
I just joined this forum. A quick note to make sure that you have seen the feature in issue 69 of The Yacht Report ?

http://www.theyachtreport.com/Articles/TYR69myair.pdf

Send me an e-mail, if you want more info.

Regards to all,
Thomas Hackman
ABB Marine
thomas.hackman@fi.abb.com

Hi Thom,

Thanks for joining.

Lurssen has diligently persued permission to publish images of AIR, but to no avail. We had hoped to cover some of the technical achievements in the form of a feature review. If this comes to pass, I hope you'll be able to share some insight.

Glad to have you aboard.

Carl

Carl,

Just send me a line and I´ll try to help you.

Merry Christmas to all.
Thomas

There is a Nordhavn 72 currently being built with DE propulsion, go to nordhavn.com for details.

Their conclusion so far is that it will be more expensive to build, but can be more fuel efficient by being able to more accuartley match power generation to the speed of the vessel, there is greater redundancy as all engines including the generators are potential power sources.

Perhaps one of the most interesting points is that full torque is available as soon as the propeller starts turning, which should help when docking.

It will be interesting to see how it performs.

Diesel Electric Explorer

A member of the YachtForums asked me to make a "Highlander green" version of my 70 m design Polara. Also to add a couple of ABB Azipods.

And since it is Christmas, his wishes came true...

Green Is Great!

Beautiful, Lars! Thanks!

Texas Dragon

Awesome ...

Deck Plans

Lars,

I've searched the forums and have found what seems to be your first posted rendering of the 70 Meter Polara Explorer. Do you also have the general arrangement for the decks that you show for many other of your designs?

I'm drooling at the thought!

Texas Dragon