Diesel Electric Conversions - Are Systems Available

[Barron]

Question guys. what conversions are available for ships with these dimensions

LOA 150
Beam 29
Draft 12
@ 300 tons

Current engine 1560 hp @ 500 - 600 rpm
Cruise @ 20knots


I know there are tons of things for commercial ships and even the small boat on the water ways. I am wondering if anyone has heard of anything for something like this ?

Thanks

[apex1]

What exactly do you mean by "conversion" ? Replacing the main with a El motor and Gennies should be no task. Are there any pictures?
And I doubt the data given! 300 tonnes? Seems to be a 50 meter fishing boat with a draught of 3,50m, almost ten meters wide? Twice that sounds lightweight! And how does such boat do 20kn with some shabby 1500 hp??

Regards
Richard

[WestVanHan]

Those measurement sound suspiciously like an older CRN I spent time on.
Or many similar Med cruising vessels.

It took 3800 hp to push it to a 14 knot top speed....

[apex1]

Originally Posted by WestVanHan

Those measurement sound suspiciously like an older CRN I spent time on.
Or many similar Med cruising vessels.
It took 3800 hp to push it to a 14 knot top speed....

Yeah, possibly a old Italian yacht, but unlikely. These slow revving engines on a yacht? I have´nt seen that.

[WestVanHan]

I have been on many of vessels such as this,and have seen quite a few 30/45 MAN engines which are rated @ 400 rpm.

As well as a few other brands.

[apex1]

Hmm, that I have´nt seen them does not mean too much I just noticed. I did not see many engine rooms on 50m boats. But maybe we get informed by Barron which sort of boat we are talking.
Anyway the data given seems to be wrong. This one (same LOA and width) had twice the power, less draught, 600 tonnes and did 17 kn with both "levers on the table".

[WestVanHan]

Of course the big/ low rpm engines are on the older steel vessels...

A relative works in the yacht industry,when I visit him in Europe he takes me along as an assistant.

I've been on about 40 large yachts.

[apex1]

I was on more, but yachtowners invite other yachtowners not for visiting engine rooms, so there have been just occasional visits on some trips. And I did not have these slow revving big engines, as most of the yachts from the 70ies on.
Richard

[Barron]

OK I am back. The boat is in fact an old fishing trawler and after getting the data sheet I found that the dimensions are

LOA 150
Beam 29
Draft 12
@ 307 tons

Current engine 1560 hp @ 500 - 600 rpm
Cruise @ 15knots

Yes I am speaking of converting to a hybrid system ( Diesel / Electric ) I have been doing research on the matter and I am not finding much available for this particular size boat.


Barron

[apex1]

Of course a D/E conversion is possible, the question remains WHY? There seems to be little sense in it.

And the data remains wrong. That boat has neither 300 tonnes nor does it 15kn cruising! I doubt 15kn max.

Richard

[baeckmo]

First, I doubt that this vessel would cruise @ 15 knots; if pushed to max, with following wind, a hungry and home-sick crew and a down hill, it might be its top speed.

Secondly, why the h... a hybrid system? Do you really have that kind of hotel load in mind? With losses in generator, propulsion motor, control system and conductors, your factual transmission efficiency at the optimum operating point will be ~80 %, at most other loads even lower.

The vessel probably is running direct drive as built, meaning a trsm efficiency = 100 %. What trade-off is worth 20 % of increased losses and a doubled installation cost???

You found no referrences to hybrid arrangements for this kind of vessel...guess why!!!


Ooops, Apex, same second....., same reflexions......

[Barron]

Your input is appreciated, However

First, I doubt that this vessel would cruise @ 15 knots; if pushed to max, with following wind, a hungry and home-sick crew and a down hill, it might be its top speed.

Unfortunately sir the cruise speed had been confirmed by the captain of this vessel..........................

Secondly, why the h... a hybrid system? Do you really have that kind of hotel load in mind? With losses in generator, propulsion motor, control system and conductors, your factual transmission efficiency at the optimum operating point will be ~80 %, at most other loads even lower.

Secondly, why not a hybrid system ? Are you versed in electric drive sir ?



The vessel probably is running direct drive as built, meaning a trsm efficiency = 100 %. What trade-off is worth 20 % of increased losses and a doubled installation cost???

The vessel does not have a direct drive, it has a geared reduction.



You found no referrences to hybrid arrangements for this kind of vessel...guess why!!!

As I have been told is these things are currently being built with off the shelf components. I had a conversation with a gentleman working with electric drive systems from Siemens. And quite frankly sir, If you cannot be helpful sir please ignore my posts.

[apex1]

Originally Posted by Barron

Your input is appreciated, However
Unfortunately sir the cruise speed had been confirmed by the captain of this vessel..........................

And I still doubt it! As I still doubt the displacement (both is just nearly impossible)

Secondly, why not a hybrid system ? Are you versed in electric drive sir ?

I would say Baeckmo is! So am I! And we do´nt see a sense (apart from the point stated, Hotel load)

The vessel does not have a direct drive, it has a geared reduction.

Than it has still a 97% or so efficiency.


As I have been told is these things are currently being built with off the shelf components. I had a conversation with a gentleman working with electric drive systems from Siemens. And quite frankly sir, If you cannot be helpful sir please ignore my posts.

These things are built since 80 years with off the shelf components, that does´nt mean they fit every purpose. In fact there are very few cases a D/E propulsion makes any sense. Icebreakers are one Cruiseships another, and then there is not much left...................

But you would make it easier for all of us when you tell us WHY? As I asked above.

Regards
Richard

[Barron]

Richard,


In the consideration of converting this boat to a private boat the "Why" as you put it comes to me in the form of these simple answers

Low Noise Level
Reduced Emissions
Better Fuel Economy
Fewer mechanical components

Also as I am told from the people at Siemens, the boat would be able to turn a bigger prop with a different pitch. Optimizing the torque from the electric motor(s) for the weight of the vessel.




Thanks

[apex1]

Originally Posted by Barron

Richard,
In the consideration of converting this boat to a private boat the "Why" as you put it comes to me in the form of these simple answers

Low Noise Level
Reduced Emissions
Better Fuel Economy
Fewer mechanical components

Also as I am told from the people at Siemens, the boat would be able to turn a bigger prop with a different pitch. Optimizing the torque from the electric motor(s) for the weight of the vessel.
Thanks

Well, lets see what remains left when going through the list.
Lower noise level: yes can be achieved with good sound shielding on the gennies. But can be done cheaper with a state of the art setup of the existing system components (though maybe not to very last decibel).
Reduced emissions: the opposite is true! With less efficiency, you have higher emissions for the same output (not to forget the large environmental footprint for the regularely new installed gensets, they do´nt last long).
Better fuel economy: no, the opposite is true! You hardly beat one of these old displacement monsters in efficiency, and a genset running at partial load (and they will do that often) is not a good solution.
Fewer mechanical components: are you joking? You have more than twice of them!
A bigger prop is hardly possible! Those boats turn always the biggest prop possible already.

Not much left!?!

Before you plan to invest some 400.000€ in such a new propulsion (and I doubt you´ll find it for less), you could better refurbish the existing engine and add a CPP! That might end up at half of the figure and you would have the best efficiency possible for such vessel, combined with a very smooth (and quiet) ride at cruising speeds.
Still speeds below 15kn believe me.

Regards
Richard