Design a pleasure canal barge in aluminum alloy with diesel-electric propulsion

[Rob Hellier]

I'm planning to design and build a 25-30 Tonne displacement barge-type vessel with constant transverse cross section in most of its length, that is 14'-16' Beam, 42-45' LOA, <3' Draught and clearance of <12'. This would allow passage of most of the pleasure and work canals in the world but still give plenty of interior space for a couple or family/group to live and/or vacation. I would ideally like the vessel to be also able to navigate in sheltered/coastal waters that allow it to transition from one canal system to another without shipping it overland or by another vessel.

Given the speeds (<5 kts) and start-stop nature of canal and river boating, using an internal combustion engine alone makes little sense from efficiency and environmental perspectives. Diesel-electric propulsion, however, makes much sense, especially since a barge's superstructure is likely to offer considerable surface area for solar generation. As well the interior volume should provide plenty of space for significant energy storage. The suppliers of diesel-electric systems (both series and parallel configurations) are maturing but are hampered in attempts by builders to incorporate their product in higher speed small craft where the advantages of diesel electric systems are lost and where the added weight of batteries reduces useful payload and performance. A slow speed barge shrugs all these problems off and is, therefore, the ideal small craft application of such technology.

Existing pleasure barges are mostly converted steel or wood work/cargo barges. Most are available in Europe, are 40-120 years old and require considerable effort to repair/maintain. Nevertheless they command prices from USD 100,000-300,000 to purchase. I wish to avoid these hassles by investing a similar amount of money to fabricate new in marine grade aluminum alloy, probably using a multichine method to simplify the construction. Such a vessel will have a considerable life-span, require far less maintenance then a steel or wooden vessel and would command a high resale value.

These are the primary conditions by which I would be interested to collaborate in a design process.

As an industrial designer, marine engineer and recreational sailor, I have considerable expertise and experience to bring to the table. These include visual communication/draughting skills, CAD skills, form giving and problem solving skills. I have less knowledge in naval architecture and no experience in practical boat building, though I do weld regularly (mostly repair and bench welding) in my work as a marine engineer. I've also done a lot of wood working and interior/house renovation work which will be useful in the design and construction of said vessel. I'm looking for persons with complimentary i.e different skill sets that are interested in collaborating in the development of the concept I've presented above.

 

[DCockey]

Several thoughts:

Create a list of requirements, needs, desires, etc. Divide the list into categories such as 1) Absolutely essential (Typically legal requirements or logistical/infrastructure constraints) 2) Primary needs (can be compromised or modified if required for feasibility) 3) Secondary needs (Desirable but would not cause compromises in categories 1 or 2) 4) Lower priority needs/desires 5) Nice to have if nothing is compromised

How would the boat be transported long distances? If over the road transport would be used then check on size limitations and associated fees and other requirements for any jurisdictions where you might want to move the boat. For example in Ontario loads over 4.3 meters / 14.1 feet appear to be more difficult to obtain a permit for than narrower loads. Oversize/overweight permits http://www.mto.gov.on.ca/english/trucks/oversize-overweight-permits.shtml

What will be your budget for the solar system and batteries? Financial considerations may limit the capacity of solar panels and battery storage even when space and weight capacity are available.

Unusual one-off boats typically have lower resale value than more common types of boats.

 

[TANSL]

I have a lot of experience working with people, amateurs, who wishing to realize their own design, they needed help regarding the naval architecture calculations, definition and calculation of the structure and, in many cases, realization of the construction drawings of the hull. My experience in metal hulls is very large, and I have managed to incorporate the techniques, the constructive strategy, used by the medium and large shipyards for the construction of small boats, which greatly reduces man hours and other construction costs.
If you think I can be of help, contact me through a personal message.

 

[Ad Hoc]

DC has given you a good check list that you need to address yourself.

Given the speeds (<5 kts) and start-stop nature of canal and river boating, using an internal combustion engine alone makes little sense from efficiency and environmental perspectives.

You're going to have to define what YOU mean by efficiency., and then what YOU mean by environmental. Since none of this is clear from your MO.

Existing pleasure barges are mostly converted steel or wood work/cargo barges. Most are available in Europe, are 40-120 years old and require considerable effort to repair/maintain.

What do you mean by considerable effort and why?

As an industrial designer, marine engineer and recreational sailor, I have considerable expertise and experience to bring to the table.

Im sure you do, but the process and disciplines involved are insufficient on their own. The design of a vessel is greater than the sum of its individual parts. Thus, focusing on one aspect, because it is your bailiwick, belies the difficulties and compromises one needs to make, from a holistic point of view. Far too many underestimate this when embarking on such a task.... it is not for the faint hearted.

 

[Rob Hellier]

David wrote: Create a list of requirements, needs, desires, etc. Divide the list into categories ...

Thanks David. That's basically a design brief. I didn't want to make my introductory statement too long, so that's my next step, once I'd gotten some feedback.

David wrote: How would the boat be transported long distances? If over the road transport ...

Roads will be a definite consideration. I'm hoping the design will allow for coastal voyaging to minimize the need to transport it other than by it's own means. Thanks for the link to Ontario's road restrictions. I'll have to find similar for EU countries like France and the Netherlands.

David wrote: What will be your budget for the solar system and batteries? Financial considerations ...

Good point, but I'm not at the stage of costing it out. I suppose to an extent, solar panels can be added as time goes by. Less so with batteries since they'll figure significantly into the weight and balance equations and total displacement, no?

David wrote: Unusual one-off boats typically have lower resale value than more common types of boats.

I'm inspired by the "peniches" "luxemotor" and "widebeam" canal boats of Europe. If you look at what's available they are all pretty much unique, given the variety of builders and the mods they've gone through in their conversions from cargo haulers to pleasure boats. But they still fetch a pretty good price. I'm thinking that if I keep their nominal dimensions and desirable features, while blending in a few features they tend not to have (such as easy access to the water surface, for example) I could tap into the enduring market for these vessels once I'm ready to pass it on. But perhaps I should heed the warnings of the responders to my post and take another look at some of the new/replica and used offerings, for example Dutch Barges For Sale: Dutch Barges, Houseboats and Commercial vessels https://www.dutchbargesforsale.co.uk/.

Thanks again and I welcome any other suggestions you may have.

 

[DCockey]

My understanding is a recreational boat must meet the extensive requirements of the EU Recreational Craft Directive to be sold in an EU country within 5 years (possibly longer) of its construction. If you plan to build the boat in Canada and then ship it to Europe you should check into any limitations on how long the boat can remain in the EU without duty/VAT being paid. Also you might want to look into what factors determine shipping costs. It sounds like your boat will be too wide to fit in a container. One possibility would be on a trailer by a RoRo (Roll On / Roll Off) vessel.

 

[Rob Hellier]

Hi Ad Hoc,

Ad Hoc wrote: You're going to have to define what YOU mean by efficiency., and then what YOU mean by environmental. Since none of this is clear from your MO.

I'm defining "efficiency" in Specific Fuel Consumption (SFC) in g/kWh of fuel. We know that a diesel motor has a higher SFC (lower efficiency) when it is run below its rated RPM. The further the actual speed is from the rated speed, the higher the SFC. This is the condition a straight diesel is going to be working under when it is propelling a pleasure barge that is navigating at modest speeds and undergoing start-stops in a canal over a period of weeks or months. However, if a diesel engine of similar capacity was used as an electrical generator to power a battery bank, it will run when required, always at its rated RPM, regardless of the pleasure barge's operating condition. Thus the SFC will be kept at/near its ideal SFC. This is the basis for the efficiency claims in diesel-electric systems. Of course we know that there are inherent losses in the energy conversions from the diesel engine's useful output to the charger to the storage medium and back to the electric motor's useful output. These raise the SFC of a diesel-electric back up, to a degree. Every vessel designer that is contemplating a diesel-electric system will therefore have to determine the "crossover speed" i.e the increase in speed at which a diesel-electric's SFC will become higher than the straight diesel's SFC. I'm nowhere near knowing what that crossover speed is! What I'm suggesting, however, is that the conditions that a pleasure barge is going to operate under presents a viable case for diesel-electric propulsion. Adding more storage capacity and generation from other sources (solar) makes the case more viable still but is not a necessity.

As for environmental efficiency, that's a tougher one to quantify. I guess I'm thinking more qualitatively i.e. not having to have the diesel idling incessantly in a lock or other locations where one is in close proximity to others is one advantage that comes immediately to mind. I don't want to get into a debate on material and energy lifecycles on something as complex as a boat.

Ad Hoc wrote: What do you mean by considerable effort and why?

I'm not trying to disparage steel or wooden boats or offend anyone that designs and builds them, and I apologize if anyone has taken offence to what I wrote. I spend many months of each year working on a steel ship! But I also experience on a daily basis the maintenance efforts to keep a steel vessel operable. The ship I work on was built during the 2nd World War. Many of the used canal boats that are out there are of similar vintages. I just don't want to be doing on my own pleasure craft what I do professionally! That's why I'm considering marine grade aluminum alloy for the construction. The research I've done on vessels that are built from this range of alloys seem to enjoy excellent longevity and have low maintenance. They also command high resale values. They have to be cared for, of course, like any vessel. An isolation transformer is a critical piece of equipment, as galvanic corrosion due to poor quality shore power connections seems to be the main culprit when an aluminum boat does experience loss of material.

Ad Hoc wrote: I'm sure you do, but the process and disciplines involved are insufficient on their own. The design of a vessel is greater than the sum of its individual parts... Far too many underestimate this when embarking on such a task.... it is not for the faint hearted.

Thank-you, Ad Hoc, for the warning. I am aware of my lack of knowledge in many areas of ship design. The fields of industrial design, marine engineering and naval architecture are far enough removed from each other to seem like foreign languages. So, I'm fluent in two of these and I'm reading up on the other (as well as other fields). I'm doing this, not thinking to be able to master all of them, but to gain some insight in just how little I know, what questions to ask and what to expect from an expert in those fields. In so doing I've discovered this great website and it's the reason I'm reaching out!

I'm sure many projects that get listed in this website get abandoned along the way. Mine might be one of them. But "you'll never succeed if you don't try". I think that's the saying :>)

 

[Ad Hoc]

I'm defining "efficiency" in Specific Fuel Consumption (SFC) in g/kWh of fuel.

Aaahh..ok. Well, that's where the comparisons start to break down, ehn ce asking the question the way I did.

Take this MAN engine for example. Same engine block, just different ratings:

and this

The rating on the left has at idle about 242g/kWh and 220 g/kWh at MCR. With its sweet spot around 218 g/kWh.
Whereas same engine, different rating on the right has, idle around 212 g/kWh and 214g/kWh at MCR and around 204g/kWh at its sweet spot.
So, it is not a good unit of measure in that sense. It is good to compare like v like, but in the whole scheme of things what is more important??.. the fuel consumption.

Every vessel designer that is contemplating a diesel-electric system will therefore have to determine the "crossover speed" i.e the increase in speed at which a diesel-electric's SFC will become higher than the straight diesel's SFC. I'm nowhere near knowing what that crossover speed is! ..

I have done just this on more than one occasion., It is not as simplistic as that. Far too many variables and each must be tailored for each individual SOR.

So, looking at a Cummins block with one as an engine and the other as a genny.

The engine at idle has around 1.5 l/h and in genny mode around 5.0l/h.
At 210kW the engine has around 20.0 l/h and the genny (MCR) around 58.0 l/h.

So again the engine appears to be better. And that's the point, it is all very specific to what you want and generalisations tend not to work out.

But the real metric is fuel consumption when underway since the vessel will be heavier going DE system, as many more bits of kit required such as inverters bigger switchboards etc etc. A rough rule of thumb, for the same power delivery to the prop, a DE system is about 3 times heavier. So the vessel has more drag which = more power required = more fuel consumption.

..Thus the SFC will be kept at/near its ideal SFC. This is the basis for the efficiency claims in diesel-electric systems. ..

Thus it is a never ending spiral, hence my question what do YOU mean about efficiency. It is not a straight forward as g/kwh as a unit of metric. The WHOLE boat as a system needs to be taken into account hence my comment that a vessel is greater than the sum of its individual parts!

.. That's why I'm considering marine grade aluminum alloy for the construction. The research I've done on vessels that are built from this range of alloys seem to enjoy excellent longevity and have low maintenance. ..

I have designed such a vessel in aluminium before (for UK and EU canals) and yes aluminium is better in terms of maintenance.

But again, one needs to look at the whole vessel and the effort by those owing such vessels of much they put into keeping a vessel well maintained. Prevention rather than cure and that requires planning and money...no matter what type of boat you have.

But "you'll never succeed if you don't try". I think that's the saying :>)

But how do YOU define and measure success.....and that's where, yet again, it is subjective.

You really need to define your SOR..Statement of Requirements.
Otherwise you'll be chasing your own tail and those that offer advice on individual parts of the design which are far too often contrary with each other. Hence what are YOU aiming at...

 

[The Q]

This link is to a narrow boat that is all electric, It may give you some information for your design..
Electric boat conversion: Electric boat conversion - drive motor https://worcesternb.blogspot.com/2007/09/electric-boat-conversion-drive-motor.html

 

[DCockey]

Take this MAN engine for example. Same engine block, just different ratings:

and this

The rating on the left has at idle about 242g/kWh and 220 g/kWh at MCR. With its sweet spot around 218 g/kWh.
Whereas same engine, different rating on the right has, idle around 212 g/kWh and 214g/kWh at MCR and around 204g/kWh at its sweet spot.
So, it is not a good unit of measure in that sense. It is good to compare like v like, but in the whole scheme of things what is more important??.. the fuel consumption.

Ad Hoc, do the two calibrations have different maximum powers?

 

[Rob Hellier]

But how do YOU define and measure success.....and that's where, yet again, it is subjective.
You really need to define your SOR..Statement of Requirements.

Thanks for the engine comparisons. Very good food for thought!
I'm working on an SOR but I'm not sure how precise I need to be in stating the requirements. Are you willing to share a typical SOR that I might use as a reference, assuming you don't consider it proprietary material? For example the canal boat that you designed? Or any pleasure vessel of a similar displacement would be useful.

 

[Rob Hellier]

Reading

This link is to a narrow boat that is all electric, It may give you some information for your design..
Electric boat conversion: Electric boat conversion - drive motor https://worcesternb.blogspot.com/2007/09/electric-boat-conversion-drive-motor.html

Reading through it now. Interesting! These narrowboats are peculiarly British! Speaking of Brits, a few years ago my wife and I were cycle touring along the Canal du Midi in France and we met upon a Mr. Fish and his wife, a very nice English retired couple. They were travelling on a canal barge which was ALL electric. There was no reciprocating engine whatsoever in the vessel. The only power source was a host of solar panels along the barge's cabin top. Mr Fish, a plumber by trade, designed the boat and its systems, had the hull made in England, then finished it himself and floated it over to France, where they had planned to spend the rest of their lives. We met them again a couple years later when we toured the same canal. He claims he had never used a generator and hadn't even connected to shore power. His secret was his top speed of 2.5 kts, as I recall. That and taking lots of stops to let the solar do their work. But in the stunning surroundings of the canals of France, why rush!? I'd love to talk to him now in more detail about his design but we never exchanged contact info. A missed opportunity!

 

[KeithO]

Rob, given your location a few thoughts.
1) Most long boats in Europe that I am aware of have a flat bottom for least draft. So a very simple hull and pretty easily built. I have watched a few youtube videos of long boat builds and they seem very basic.
2) There are additional options to aluminum. Here in MI, 5086 marine grade plate is running about $3.30/lb + sales tax. Korten steel is running under $0.68/lb and is a lot more rust resistant than mild steel. Of course you will use more of it by weight since the density is double but then aluminum needs thicker sections so the hull is not likely to be double the weight compared to aluminum. Super exotic would be to use 300 series stainless, which is currently running $2.36/lb. I havent heard of anyone using stainless steel, but as you can see, on a by weight basis you could build a boat out of 304 stainless for less money in material than marine grade aluminum plate.
3) For your propulsion system, you might want to consider a hybrid concept instead of the Diesel electric that you are proposing. In other words, you have a diesel engine with a transmission which can be engaged and disengaged "as normal" and is optimized for long passages (transmission ratio, prop diameter and pitch etc). In addition you have an electric motor coupled to the prop shaft which you can drive from battery power or directly from a solar array independent of the diesel engine. Or you can drive it with the diesel and the electric system if it is an emergency of some sort... If your main engine has a good alternator. then you have a way to charge batteries while motoring and are not totally dependent on the weather for electric power. Parker sells what they refer to as "kit motors" which consist of a stator and a rotor, the rotor having permanent magnets. The rotor can be mounted to the prop shaft using a Fenner taper lock device (so you can still remove the propshaft) and the stator is mounted to a housing that can be supported by a piece of plate welded to the hull. The stator housing has to be designed to provide the windings with adequate cooling, something cooled by water would be the most effective.

I think you will find that a hybrid powertrain provides the best of both worlds, best engine efficiency when you need more power and the option to run purely electric when the power requirements are lower. And all this without losing 15% in efficiency going from Crankshaft to alternator, then 5-10% more going through the motor drive and then another 5-10% in the electric motor itself. If that was your only option, that would really suck. And on top of it all, you would need a much larger alternator and electric drive motor and motor drive = $$$$$

 

[Rob Hellier]

Most long boats in Europe that I am aware of have a flat bottom for least draft. So a very simple hull and pretty easily built. I have watched a few youtube videos of long boat builds and they seem very basic.

Yes, I was envisioning a flat bottom. When I mentioned "multichine" I envisaged a flat bottom, then a 2nd longitudinal plate for the turn of the bilge before the vertical (or nearly so) side of the vessel. Possibly the turn of the bilge would be in two longitudinal plates if it improves the boat's hydrodynamics. A great example of this type of hull is the French made OVNI sailboat by Alubat. OVNI 395 https://www.alubat.fr/ovni-395

I had no idea that Corten steel was that much less expensive than 5086. My buddy recently purchased a schooner made from Corten steel and he's very pleased with its state of repair. Mind you I think it's only been fresh water sailed...

The hybrid diesel-electric system with electric motor coupled to the prop shaft of a diesel that you describe is also called a "Parallel Diesel-Electric" and was in my original write-up. But thank-you for your thoughts on this. I have to take heed of AdHoc's comments, however, to carefully consider my Statement Of Requirements and not to get swooned into adopting a technology unless it provides actual advantages in greater proportion to its cost, complexity and weight.

 

[Ad Hoc]

...do the two calibrations have different maximum powers?

Yes they do.

... His secret was his top speed of 2.5 kts, as I recall. That and taking lots of stops to let the solar do their work. ...

That's fine if there is no running tidal stream in or near an estuary or having to fight manoeuvering on a very windy day. So where you wish to travel will also dictate the power you need, not just for top end speed.
Hence defining the SOR.

I'm working on an SOR but I'm not sure how precise I need to be in stating the requirements. ...

It is just a simple list of things YOU want for the vessel in terms of its performance, its ability to carry, range, paylaod, dimensions outfitting etc etc. Then of course the important one...cost!

To embark on such a quest should not be done on the fly - so to speak. You must define everything you want the vessel to be, before you spend any money. Define it, rough it out on paper/CAD..and then cost it....then you'll know where you stand, otherwise you'll just be chasing your own tail. If you don't know the basics of what you want nor the costs before you start....it will be doomed to failure like so many home builds that do not keep an eye on the design v cost.