Diesel electric twin outboard self build.. I think :)

[Badger3]

Hello one and all I was prompted to start a new thread....I am thinking twin deisel electric 5kw out boards....to move 40 foot by 10 foot open barge....why you ask?

At the mo I have a perfectly adequate living space on the back of my bedford tm 4x4 truck, I don't want to sell it..... so I build an open barge, drop my living quarters in.... plug it into my generator along with my twin outboards and away I go....simples....or so the meerkats tell us

The box is ex army too made from aliuminum so no rusting for me, it measure 15x8 foot the rest of the barge will be open to do as I wish with.....I thought deisel electric because my box is all electic now why change it or build a new one?.....so if I want to travel the water ways I go by barge or if I want to go,on holiday some where nice transfer the box back to the truck and Europe here we come....your thoughts please.

[luctor et emergo]

An excellent idea. You get the best of both worlds.

[Jerra]

A couple of questions spring to my inexperienced mind. Will the box from the 4x4 fit within the gunwales of a boat that has to have an outside dimension of 6 ft 10 in or are you thinking of a wide beam. What will the air draught be?

[Badger3]

A couple of questions spring to my inexperienced mind. Will the box from the 4x4 fit within the gunwales of a boat that has to have an outside dimension of 6 ft 10 in or are you thinking of a wide beam. What will the air draught be?

I did put in my first post 40 foot by 10 foot so my 8 x 15 box will slip in easy

Also the box is only 6 foot high.....so when it is in the flat bottom barge air draft is to be about 4 foot ish be pending how much other stuff I cram on lol

[Bill]

Any chance of a picture of the truck, I can't quite visualise what you currently have. But sounds like a possible plan. How will you transfer the bits across? I assume it must weigh a fair bit.

[Graham Davis]

I get the "living quarters" bit, sort of a demountable living pod, but I question the suitability of a twin outdrive system. Would it be better to convert a diesel driven wideboat to an electric drive one, using the current fitted gearbox/prop?

 

Further.

How are you going to deal with your grey waste water? In the "truck mount" you have room underneath to drain it away, but if the "pod" is on the base of a barge.........................?

[Guest]

An interesting idea, and something different

 

Similar idea using a touring caravan, though diesel powered in this instance:

 

[Badger3]

Bill...... sorry I am on my iPad and it won't accept pics when I get on my laptop sometime I will update it

 

Graham.......the barge will be a self build I have a friend designing for me and preparing a cutting list, in therory a big jigsaw

So no engine bay or anything just an open barge, so no gear box etc...hence the twin electric outboard, I don't think one will do it to be honest.

The grey waste won't be a problem....I will use my girlfriends boat it will be a nice big bedroom with a garend with real grass and room at the front for??? Not sure yet, I have alot of tools so maybe a workshop

 

Cat weasel ....love the pic like most ideas not original !!!! But should be fun building it

[Guest]

Do you already have the outboards, or some in mind?

[BEngo]

I trust that your existing 'pod' complies with the requirements of the Boat Safety Scheme....

 

 

N

[Guest]

I trust that your existing 'pod' complies with the requirements of the Boat Safety Scheme....

 

 

N

I can think of a very quick solution to that problem, but aint going to put it for fear of getting slated

[BEngo]

So can I but I think it might be a rather obvious ploy. The generator and all the 'stuff' for the electric outboards will still need to comply though.

 

Complying with the RCD might also be 'interesting' but since I suspect that there won't be much demand for the boat if 'placed on the market' that should not be too difficult to avoid for 5 years.

 

 

What sort of voltage would you want to run the electric outboards at? Is the idea some sort of hybrid diesel-electric or will the generator have to run continuously when the craft is on the move? I know the small ones are 12 V or 24 V but I'm not familiar with a 10 KW one.

 

Sizing the genny will be interesting. Unless you have some battery reserve you will need at least 25 KVA to provide full power from the outboards (though I can't see that that should ever be needed). Most of the time the genny will be doing bugger all though since going along a canal does not require more than about 3-6 KW. Allow a little for hotel loads and the genny engine is still at only part power for most of the time. That is not good for diesels.

 

Direct drive motors tend to be 48 or 72 V DC. (or 3-phase with a VFD but that's a pricey solution for 20 KW.) If the outboards are 48/72 V How will you get sufficient 12/24 V for the Pod?

 

Sounds like an interesting project. Do keep us posted.

 

 

 

 

 

N

[Badger3]

Do you already have the outboards, or some in mind?

I was thinking around a 10hp petrol one....get rid of the petrol drive and replace with electic...my thinking was. 10hp outboard would struggle to push said barge....but 2 times engines should do the trick and not be flat out at crusing speed, also on a 10hp petrol outboard the prop would be some where about the right size ??

Do you already have the outboards, or some in mind?

I was thinking around a 10hp petrol one....get rid of the petrol drive and replace with electic...my thinking was. 10hp outboard would struggle to push said barge....but 2 times engines should do the trick and not be flat out at crusing speed, also on a 10hp petrol outboard the prop would be some where about the right size ??

I trust that your existing 'pod' complies with the requirements of the Boat Safety Scheme....N

At the moment I am not sure.....but will it have to as it is not a permanent fixture? The boat rego etc will be for an open barge.... With a grass lawn, not sure if that has to comply or not

[Badger3]

So can I but I think it might be a rather obvious ploy. The generator and all the 'stuff' for the electric outboards will still need to comply though.Complying with the RCD might also be 'interesting' but since I suspect that there won't be much demand for the boat if 'placed on the market' that should not be too difficult to avoid for 5 years.What sort of voltage would you want to run the electric outboards at? Is the idea some sort of hybrid diesel-electric or will the generator have to run continuously when the craft is on the move? I know the small ones are 12 V or 24 V but I'm not familiar with a 10 KW one.Sizing the genny will be interesting. Unless you have some battery reserve you will need at least 25 KVA to provide full power from the outboards (though I can't see that that should ever be needed). Most of the time the genny will be doing bugger all though since going along a canal does not require more than about 3-6 KW. Allow a little for hotel loads and the genny engine is still at only part power for most of the time. That is not good for diesels.Direct drive motors tend to be 48 or 72 V DC. (or 3-phase with a VFD but that's a pricey solution for 20 KW.) If the outboards are 48/72 V How will you get sufficient 12/24 V for the Pod?Sounds like an interesting project. Do keep us posted.N

 

voltages and gerarators are being planned as I type....I am thinking along the lines of 10kw (13kva) power source ..... Twin 5 kw electric motors tuned down to 4 kw each max ( the motor supply company have programable motors ) that way I never exceed the genartors max.....as for running the pod, it runs itself via solar now it is going to be a nice big bedroom and chilling area cooking showers etc all done on my girlfriends boat....so the power is only for propulsion....I will of course keep you all posted

Namaste .

[koukouvagia]

The idea of a pod has been tried before. This was what Owl looked like when I bought it in 1989. On the bank you can see the living quarters used by the previous owner. It consisted of a fully fitted cabin which could be lifted out. I seem to remember that it had a genny to provide power when on the move. I did toy with the idea of keeping it, but it never looked right IMO. However, some people might say it was preferable to do this to an historic boat than put on a permanent under cloth steel conversion.

 

 

 

[ditchcrawler]

I trust that your existing 'pod' complies with the requirements of the Boat Safety Scheme....

 

 

N

Does it need to, it would be cargo?

[Guest]

Does it need to, it would be cargo?

Interesting thought.

[RLWP]

Interesting thought.

 

In who's mind, our's or CRT's

 

Richard

[Teadaemon]

Ok, I see what you're trying to do - basically the outboards are just the drive trains.

 

Whilst it may be possible to lash up something that will work to some extent, I have to say you're never going to get an efficient system based around that idea.

 

Electric motors and internal combustion engines have radically different characteristics - there's no such thing as 'tickover' for an electric motor for a start, and the torque curves are completely different.

 

For an electric motor to work efficiently you want to swing the largest diameter, largest blade area prop you can, as slowly as possible (this is because the torque curve tends towards infinity as revolutions tend towards zero). Compare that to a petrol engine, which will probably produce maximum torque at or near to maximum revs (so a small diameter, low blade area prop spinning fast is more efficient).

 

I really wouldn't want to comment on the BSS implications of your proposed idea, except to say that if CaRT licence conditions are anything like the Broads Authority byelaws, there's a general requirement to maintain the vessel in a state that complies with the BSS at all times, even though it's only inspected once every four years. If I were asked to do a BSS on such a vessel with no 'cargo', then for starters I'd be concerned that it might be used for commercial purposes (and thus require an examination to a different set of checks, currently the 2002 edition), and if I were satisfied that it was a private vessel the records I'd make (and upload to the BSS computer system) would include a note that the cargo area was unoccupied. I believe that CaRT have access to these records (they can certainly see enough to check if a boat has a current BSS or not), and you may find that subsequently craning accommodation on board might be noticed and acted upon (again, if they're anything like the Broads Authority, they retain the right to conduct a hazardous boat examination if they suspect non-compliance).

[Guest]

 

In who's mind, our's or CRT's

 

Richard

Mine.

[RLWP]

Mine.

 

And mine. Weird, isn't it

 

Have you got the voices as well?

 

Richard

[Guest]

 

And mine. Weird, isn't it

 

Have you got the voices as well?

 

Richard

Aye, got the voices. Been mad all me life. I'm happy in my own little world though