Efficient Powerboats vs Efficient Sailboats (Running Cost Comparison)

[Marc1]

I doubt that a diesel electric set up could be patented, it is as old as diesel locomotives. That is just a small version.
The novelty is its size. Usually diesel electric set up for boats are huge and cost as much as the boat or more.

The consensus on diesel electric is that their advantage consist in running the diesel engine always at optimal load where they are at it's most efficient in converting fuel into KW. So you have an efficient set up when you run your diesel engine at optimal rpm all the time, regardless if cruising along at 5 knots or racing ahead of a storm.
In this set up that is partially lost since the generator is on the shaft and when charging you will have to adjust the revs on the diesel engine according to the speed you need and not full blast as you should for efficiency.
This would be overcome by having a diesel generator set up anywhere else and an electric motor running the propeller. A variable pitch propeller that can be set for minimum drag when sailing would be ideal.

You also say that the little diesel engine generates little heat. The heat generated by any diesel engine is a function of the power output and any size engine if requested to do little work will generate little heat. Yet if you want to get 40HP out of a Honda lawnmower engine you will have to squeeze it out of it. I don't dispute that it is possible, (not necessarily desirable) yet it will give out the amount of heat that corresponds to 40HP, be it Honda or Perkins no much difference at all. A keel cooling system will be much more desirable than a car radiator. In fact I don't think you could run an engine legally with a car radiator in an enclosed space and depending on an electric fan. Not in Australia anyway.

As for solar panels, well I am no expert and I use to think they where the bees knees, but I was shown the figures and they don't really cut the mustard yet. May be some super duper very expensive NASA technology yes, not what is commercially available, in other words it will be ok to keep the lights on but not to power the propeller for more than one hour or two.

I think however that there is a lot of merit to try home made small size diesel electric system on a vessel. I whish more people did more experiments on this line.

[cat man do]

Originally Posted by Beemer

So since you're carrying a few tons of ballast anyway, why not have it be in the form of batteries?

What be this ballast stuff you speak of?
and how does all this additional weight aid efficiency?

Dave

[BillAU]

G'day Dave,

Thanks for the PM and the link to this thread. It makes interesting reading, even if a wee bit confusing at times, for someone in my boat

I'm a retired seaman, busting to sell-up and get back to sea, live aboard full time, bumm around the Hawksbury River for our Oz summer, then head north for our winter, plan on crusing all along the Qld coast, (avoiding tourist traps) up and around the top-end as far as Broom and perhaps heading into Asia for a time...Who knows what the future holds or where we'll end-up.

Anyway Dave, in the start I believed a sail-boat was for me, a 36' Tri' but when I thought of what I want/need on-board to be "self sufficent" I soon discovered I would need a bigger boat! Then after finding and reading Sue and Philips site on Power Crusing On A Budget, I came to believe a trawler type power cruser would suit my needs better and, it would suit the area I planned to cruse.
The problem I find while looking for a trawler type cruiser...I can not find a 37' to 40' (Blue Water Capable) with the range I would like, nor do they seem to have the space to install larger diesel tanks.
All suitable trawler/ex-trawlers I have found (in my price brackeet) here, Canada and the States, are from 47' up, "all" have been built in Steel and from the ones I've found online, I believe the best of the bunch (value for money wise) is a 50' Bruce Roberts Custom Waverunner Trawler. Also, "just about "all" the MV's I class as "long range MV's" have a cruising range of 3000 nm and cruse at 7 kn with a top speed of around 9-10 kn and "all" have a draft of 5-6'.

Now then, I would be the only person aboard most of the time, from time to time my daughter, her husband and daughter may join me for a diving holiday. I don't dive but they are right into it. Anyway, the largest boat I have ever handled was a 35' in-shore timber built trawler. So a 50' steel MV for little old me is, basically too much boat! Or is it?

I'm checking MV's because I have never sailed a boat, any boat. At 67 I'm getting to long in the tooth to start learning about masts, sails, winches and all the other gear that goes with a SV. I don't fancy hoisting and lowering sails for different weather, or having to go-up a mast when called for. Having suffered two heart attacks, I don't think I have the strength anymore I've talked things over with my Doc' and he says, if that's what I want to do...Go do it and enjoy!

Dave, as a boat builder living and have sailed a lot...In a lot of the area I plan on cruising, what do you think to me in a Steel 50' MV with a 6' draft? Would the boat be suitable for the Whitsundays and the Top-End? I "wish" I had the cash to have you build a Cat like the one your building for yourself but I don't She's a beaut mate

I guess I could always pick-up a couple of back-packers, interested in seeing parts of our beautiful country one only gets to see with a boat...Free sea travel with tucker, mostly fresh fish, Morton Bay bugs, Mud crabs and fresh fruit, what more could anyone want for a bit of help on-board, I imagin that would apeal to a lot of back-packers

Bill

[cat man do]

Originally Posted by BillAU

The problem I find while looking for a trawler type cruiser...I can not find a 37' to 40' (Blue Water Capable) with the range I would like, nor do they seem to have the space to install larger diesel tanks.

How about something like these? In the budget or lower?
(I am not suggesting either of these vessels)


Windstar 36 MOTORSAILER: MOTORSAILER Sail Boat For Sale


Clipper 34 Footer: Clipper 34 Boat For Sale

I believe the best of the bunch (value for money wise) is a 50' Bruce Roberts Custom Waverunner Trawler.

Looks pretty rough that one, but looks can be deceiving.
I personally would do my homework on second hand steelies, this story springs to mind The saving of WhiteBird

Also, "just about "all" the MV's I class as "long range MV's" have a cruising range of 3000 nm and cruse at 7 kn with a top speed of around 9-10 kn and "all" have a draft of 5-6'.

Why 3000nm in tanks?
I helped take a crayboat to Vanuatu recently and it had possibly 2 x 200l tanks, but we did the trip with 44 gallon drums standing upright on deck and siphoned as required.

.In a lot of the area I plan on cruising, what do you think to me in a Steel 50' MV with a 6' draft? Would the boat be suitable for the Whitsundays and the Top-End?

Not for me it wouldn't be, specifically needed under 3 ft for a lot of the "special" places I like to get into and anchor

Will you really be buying in Canada and bringing her here?
Surely more beneficial to throw the fuel used in that instance into a better local boat.

I "wish" I had the cash to have you build a Cat like the one your building for yourself but I don't She's a beaut mate

Thanks

I wish I had the cash to just go out and buy one or get some idiot to build her as well.

[BillAU]

Originally Posted by cat man do

How about something like these? In the budget or lower?
(I am not suggesting either of these vessels)


Windstar 36 MOTORSAILER: MOTORSAILER Sail Boat For Sale


Clipper 34 Footer: Clipper 34 Boat For Sale

Looks pretty rough that one, but looks can be deceiving.
I personally would do my homework on second hand steelies, this story springs to mind The saving of WhiteBird

Why 3000nm in tanks?
I helped take a crayboat to Vanuatu recently and it had possibly 2 x 200l tanks, but we did the trip with 44 gallon drums standing upright on deck and siphoned as required.

Not for me it wouldn't be, specifically needed under 3 ft for a lot of the "special" places I like to get into and anchor

Will you really be buying in Canada and bringing her here?
Surely more beneficial to throw the fuel used in that instance into a better local boat.

Thanks

I wish I had the cash to just go out and buy one or get some idiot to build her as well.

G'day Dave,

I don't think either of the two are suitable for a long haul, I don't need a boat this week, I can bid my time and perhaps find what I have in mind here.

I hear ya loud and clear when you say, be careful in buying a steel boat.
I have always thought when buying "anything" but specially cars and boats, it is 'Buyer beware'! A mate of mine in the UK bought a fishing trawler...After getting a survey! The boat sprung a plank and sank...On his first day out!
Another mate bought a good looking fibreglass sail-boat in Durban, South Africa...Once again after survey! The surveyor must have been blind as the hull was riddled with Osmosis! So do I believe in "Buyer Beware"? Bet your Cat I do!

Why 3000nm in tanks?
I helped take a crayboat to Vanuatu recently and it had possibly 2 x 200l tanks, but we did the trip with 44 gallon drums standing upright on deck and siphoned as required.

You already have the answer to that, I don't want 44s all over the deck...Or anywhere else for that matter.

Not for me it wouldn't be, specifically needed under 3 ft for a lot of the "special" places I like to get into and anchor

That was one of the reasons I was looking at Tri's, shallow draft. Who knows, I may change my mind...again! And go back to checking Tri's but I have never sailed any vessel and I don't know if I would be doing myself any favors by buying any sail-boat. I do like the lines of some Tri's but the learning curve and at times, having to go-up the mast is a turn-off.

Will you really be buying in Canada and bringing her here?
Surely more beneficial to throw the fuel used in that instance into a better local boat.

You could be right about that but, boats here "seem" to cost quite a bit more than in Canada and the States. Besides, a voyage down the Atlantic seaboard from cities on the Eastern seaboard of Canada or the USA, through the Panama Canal and over to Tahiti, then Island hoping back to Oz would be a trip of a lifetime, don't you think?
Back in the early 70s I worked for the United Fruit Company out of Hobokin, New Jersey. Old steamer fridge freighters between the States and Honduras back then, hot work but good times.

Thanks for your tips and good luck with that nice Cat of yours

Bill

[cat man do]

Originally Posted by BillAU

I don't think either of the two are suitable for a long haul, I don't need a boat this week, I can bid my time and perhaps find what I have in mind here.

I thought you said in one of your posts that ideally you were after 35 to 40 feet?
This be them

Why 3000nm in tanks?
I helped take a crayboat to Vanuatu recently and it had possibly 2 x 200l tanks, but we did the trip with 44 gallon drums standing upright on deck and siphoned as required.

The point would be that you only need the large fuel supply while on passage.
When you arrive at the intended cruising ground it seems pointless to have 2000 + KG of extra weight (fuel) onboard for the hell of it, especially if tavelling 50-100nm in a day and then being parked for a week exploring

Will you really be buying in Canada and bringing her here?
Surely more beneficial to throw the fuel used in that instance into a better local boat.

Great trip

Stump up the extra cash and get this with 2876.91296 litres of tankage



1953 U.S. Navy design Pilothouse Liveaboard Cruising Trawler Commercial Boat For

If I wasn't so far into the build, this is the sort of mono that could seriously tempt me.

[BillAU]

Yes Dave, I've been looking at that US Navy designed beauty since last year, she truely is a beauty and I would love to own her, as would "any" seaman I'm sure.
One of the other blokes on the forum put me on to her a month or so back but at 119,640.00 USD = 133,252.21 AU she's out of my price bracket.
After first looking at her I talked with Oz customs about importing her. If the delivery cost $6000 from Washington, landed in Oz, delivery cost, tax and duty would take the price to $160,508AU and, I can't afford that amount if I want to keep back-up cash

If I did have the cash to buy her, I would like to cruise down from Sequim, WA to Los Angeles then over to Hawaii but, the distance between Los Angeles and Honolulu, Hawaii is 2551 miles (4105 km) so I don't think her tankage of 760 gals is going to cut it...Pitty they don't state what her range is. Anyway, I guess she would have to piggy-back on a freighter to Australia...No way would I carry 44s on her decks

Guess I'll keep looking.

Bill

[cat man do]

Originally Posted by BillAU

..No way would I carry 44s on her decks

Why?

You can put rubber mat under and around to prevent chafe

or use these


Underwater Salvage Lift Bags: Fuel & Water Bladder Tanks For Boats And Aircraft: TurtlePac

or these in plastic



55 Gallon Barrel/Drum - Blue, Plastic Barrels, Plastic Drums, Metal Drums, Plastic Totes, Plastic Storage Containers - ArizonaBarrels.com

On another delivery I did on this vessel


They had a larger version of these X2 down back before the seats went in (Seats were on the roof on the trip over)


Perhaps you can explain this compelling need to have internal tankage for a one off trip?

It will certainly limit the amount of vessels that show up on your list.

.

[BillAU]

G'day Dave,

I started providing answers to your question: Perhaps you can explain this compelling need to have internal tankage for a one off trip?

My reply was becoming a book so to shorten it, let's just say, I know myself quite well and there's every chance the large internal fuel tanks “would not” only be required as a one-off.

Any plans made by anyone are subject to change for one reason or another, so, I would like to be prepared, as well as I could be prepared, should I take it into my head to go cruising/sailing Blue Waters and foreign shores.

Cheers mate.

Bill

[Brent Swain]

Originally Posted by cat man do

Just wondering if anyone has looked hard at the cost of running a performance sailing boat [build and maitenance ] vs long,light low powered boats???

The mainsail which I bought for $100 in 1980 has just given out, after 6 Pacific crossings. How does that work out in miles per gallon? I can spend a winter in the South Pacific for under $3000, including getting there and back. How much motoring distance can you get for that much money, and have enough left over to live? There is no comparison. On one trip to Tahiti and back to BC, I had no engine . So what were my fuel costs ? One couple sailed one of my 36 footers to Australia from BC on 35 gallons of fuel. Try that in a powerboat, of any kind.It's a no brainer.

[BillAU]

Originally Posted by Brent Swain

The mainsail which I bought for $100 in 1980 has just given out, after 6 Pacific crossings. How does that work out in miles per gallon? I can spend a winter in the South Pacific for under $3000, including getting there and back. How much motoring distance can you get for that much money, and have enough left over to live? There is no comparison. On one trip to Tahiti and back to BC, I had no engine . So what were my fuel costs ? One couple sailed one of my 36 footers to Australia from BC on 35 gallons of fuel. Try that in a powerboat, of any kind.It's a no brainer.

G'day Brent,

Thanks for sticking your oar in mate, that's what I'm looking for, real life experiences
I have a couple of compounding facts for even considering a power boat over a sail boat...My preference are Tri's.
1: I'm a retired seaman but no sailor and as you are well aware, there is a big difference. As I said on another thread, the only times I've been out on a sail boat, I'm sure I was only there as ballast, so I know nothing about sailing, nor have I found a sailing club around my neck of the beach where I can learn to handle a 36' plus sail boat, preferaably a Tri.

2: At my age, 67 (my eldest child? Is 46) I don't fancy going-up a mast to do an essential job while along side, never mind having to do so while at sea.

3: There's a lot more space below on, say, a 40' power boat than on a 40' mono sail boat. I've been informed there's even less on a 40' Tri, because of the narrow hull. Comforts become a way of life for most people in my age group.

So in my situ' a motor vessle makes more sense...I think
By the way, how many times did you need to go up the mast on those 6 Pacific crossings, or in the past, say 5 years?

Cheers Brent,

Bill

[beau]

This is my next boat,
A scaled up version of my current 39 ft tri
A motor sailor with the main aspect of motoring up to 20 knots with
2 x 125hp outboards. Cruise at 10-15 knots under motor (fast displacement hull)
Or sail downwind with a low cost sail plan (oceanic lateen)

[cat man do]

Originally Posted by Brent Swain

The mainsail which I bought for $100 in 1980 has just given out, after 6 Pacific crossings. How does that work out in miles per gallon? I can spend a winter in the South Pacific for under $3000, including getting there and back. How much motoring distance can you get for that much money, and have enough left over to live?

Yawn

Perhaps you missed this bit, even though you quoted it

Originally Posted by cat man do
Just wondering if anyone has looked hard at the cost of running a performance sailing boat [build and maitenance ] vs long,light low powered boats???

You do not have a performance boat
You do not have performance sails
You do not have a performance rig

people may have sailed around the world in an old bathtub with a broom for a mast and used nappies for sails, but clearly, this is not what I am making comparisons against.

I made that clear at the start of this thread

Originally Posted by Brent Swain

There is no comparison.

Indeed you are correct

On one trip to Tahiti and back to BC, I had no engine . So what were my fuel costs ? One couple sailed one of my 36 footers to Australia from BC on 35 gallons of fuel. Try that in a powerboat, of any kind.It's a no brainer.

Correct again, it is a no brainer

Take into account that they already had an engine (so no additional expense)
and then deduct the cost of the rig etc and convert that into fuel?

How does it look now?

[cat man do]

Originally Posted by beau

This is my next boat,
A scaled up version of my current 39 ft tri
A motor sailor with the main aspect of motoring up to 20 knots with
2 x 125hp outboards. Cruise at 10-15 knots under motor (fast displacement hull)
Or sail downwind with a low cost sail plan (oceanic lateen)

Nice one Beau

can you put up a few links for me with more information on this sail plan please?

Nice and simple and I'm starting to get an interest in a short rigged downhill sail as the Kitesail ideas dont seem to be progressing fast enough

[beau]

Dave,
I will have a look back at some of my early research and let you know.

Basically you have a short mast (cheap) and two aluminium or bamboo spars on each side of the sail. The micronesians use the first system the polynesians the second one.
I have rigged my boat up for both.

They are the most efficient sailplan (marchal) based on sail area, because of the higher % of sail area which is high up where there is the strongest wind. The experts also talk a lot about vortex formation at the top of the sail, but I really don't know about that.
These sails don't flog because of the spars on either side and they are easy to control with an added line from the top of the mast to the lower spar which can be used to spill or furl the sail.
The sail is cut flat (cheap) I used a heavy duty red spinnaker cloth. (Professionally made by a sailmaker)

It is not possible to tack but you can gybe.
I only use mine with the wind behind, sometimes with the motor on (low revs) and sometimes sail only.

One aspect I have now confirmed.
With a fast displacement hull either on a cat (narrow hull beam) or on my tri (Triangular, and fine entry) you only need 25hp/ton to achieve 20 knots of speed through the water, compared to a planeing hull which needs a minimum of 60 hp /ton to plane and a displacement hull gets buried by the bow wave, at speed.(sg.root of the water line etc)