The Offshore Voyaging Reference Site

Motorboating and Sailing Compared—Part 2

I continue the story of our trip on a Nordhavn 55 and then look at seaworthiness, fuel burn and my thinking on the related environmental issues, and then finish up with what all of this means to Phyllis and me personally.

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Great article, read with interest as I am also considering a move to the dark side. LOA vs LOA, a trawler offers at least double and probably 3 times the useable floor area for living. It also usually offers vastly better maintenance access. On that basis, the fuel economy factor begins to look less one sided.

You didn’t mention noise and vibration levels on your cruise. Were they at all pervasive? Or were they markedly less than a sailboat? How are oil changes handled on the run? Surely, they don’t stop the boat every 100 hours to change oil?

I’ll leave the ACC debate to others more erudite than I. After a year spent trying to understand it, I’m still at a loss to really understand it. Despite which, I am an “alarmist” as the “deniers” would label me. . Both sides seem to only want to hurl abuse at each other. Quite a nasty level of debate.


Re. oil changes: On motor vessels that see a lot of hours, it’s common to fit a bypass oil filter system. These devices, combined with routine lab analysis of oil samples, can greatly improve engine longevity when operating with extended oil change intervals.

Gust Stringos

What are your thoughts on multihulls as a transition from sloops for creaky sailors?

Rick Salsman

Hi John:
An interesting read, you leave me with so many follow up questions to pursue each time. In other words you do get me thinking, thank you.
On the fuel burn side of things I have a friend over here with a N46 and though I do like the amenities on the boat but I think that the long slim idea you have is much more efficient and should allow faster speeds with less relative fuel burn.
During your last series on Motorboats for Sailors you alluded to doing a piece on power cats or perhaps a “rig-less”,previous, sailing cat. You mentioned in this post you were reading Tarjan’s Catamaran book.
I would love to hear your thoughts on a Cat as a possible sailors motorboat.
Regards from Sicily, Rick


Hi John,
65′ displacement power catamaran running at 30 knots and producing virtually no wake:

As to John’s lament that there are no production motor cats like this he is absolutely correct. Production boats, be they sailboats or motor yachts, are designed by bean counters targeting the lowest common denominator that will create the largest profit margin. Advertising is the means for overcoming deficiencies, not good design. Because “value” is created by propaganda rather than design, junk boats often have greater resale value than far superior custom ones.

Great boats are created by great designers like Steve Dashew or the Boreal partners who, for whatever reason don’t compromise their vision. And some even survive and prosper.

I guarantee you can have a power catamaran like the one in the video built with a yachty interior for far less than a new Nordhaven. And it will have a design heritage developed and tested by hundreds of thousands of miles of commercial usage over the course of two decades. But do it because you want to own and use a superior boat, not to sell after you done your Caribbean tour and flip the money into a condo in Miami.


Certainly a step in the direction of more efficient hull forms, but not exactly “attainable”. If this thing is built in carbon its cost was far more than Dashew’s FPB 78. Still a motor yacht first and a catamaran second.

Simplify, simplify, simplify— in construction method, materials,machinery, and design.


I’ve also read (I think it might have been on Steve Dashew’s blog) that for ocean passages – people don’t like catamarans because they have no self-righting ability. If they ever get flipped over from a large wave – there is absolutely no way to recover. Many of the most serious off-shore cruisers like the Dashew FPB series, and the newer Artnautica 58 long range cruiser – are designed with self-righting ability in the event of capsize.

Scott Flanders

I did a rough fuel cost calculation at the 10 year mark. At the time she had just finished a circumnavigation having done roughly 60k nm at an average speed in the 6.3-4 knot range including everything from chugging slowly to see or rocketing on a tide ride Her fuel mileage was a little over 3nm/USG. At an average world fuel price of $5/USG – it’s actually less – we spent 10k per year on fuel not including generator or diesel heater burn. Most budgets would support this considering there isn’t any rig expense.

Yes she is slow compared to sail in good conditions but I suppose the overall average speed is near the same over a year for a similar size boat. This year from Iceland, Greenland, etc to NYC currently she has averaged 6.8 knots, above her usual. We pushed the throttle up to shorten the time at sea on the two sea stretches but because of favorable wind and currents she averaged 7.1knots until Labrador and still maintained over 3nm/USG. In all fairness these conditions are rare.

Neither are perfect but we all see the same things and we all have fun which is the bottom line.

If any of you are considering the dark side seriously and plan to go somewhere other than coastal cruising, a good source if information is on the site, Voyage of Egret. Every nm from Turkey, around the world to today is documented including at sea conditions, landfalls,etc as well as a fair amount of technical information. There are photos to document the miles as well.



Yep. fuel is too cheap.


Great article(s). I, like many sailors I’m sure, have looked at the Nordhavns with a skeptical yet interested eye. As an engineer I am not surprised by your analysis with regards to fuel, steering and stability. But, what struck me the most were the more real world issues of pitch and maintenance. Even if I were to sell my house and buy a giant N50+ I just can’t see keeping up with the maintenance routine of all the systems myself and nothing is more frustrating than the cost of outsourcing (even if you have the bucks).

As for the environmental debate in the last thread I think it really comes down to that age old debate of moral absolutism vs moral relativism. As you said very eloquently — selling (or shuttering) a big house in New England and taking your N50 down to the Caribbean for the season might be a net envrio savings, but it’s still not the lowest footprint. We could all run vegetable oil in our cars and harvest ear wax for candles I suppose. But at some point we have to celebrate any gains in efficiency — although in fairness it is hard to paint a 100,000 lb yacht for two as “green” under any circumstances.

Again, great article and great debate. Keep em comin’.


None of the boats you list are what I would classify as being anywhere close to “Attainable”. If you were trying to compare offshore sailing to offshore motorboating, you should look beyond the floating condos. I would strongly recommend analyzing George Buehler’s Diesel Duck line of designs. Seahorse Marine produces a line of steel ducks that meet a range of space/size/comfort levels – many of which would be much much closer to your MC experience in terms of beam/length/displacement. I think that would be a for more logical comparison – most Ducks even have a sailing rig to reduce fuel burn!


Concerning houses & boats environmental impacts, I understand that there has been some debate about converted canal barges or similar new-built floating houses vs. classic houses.
The general ideas are that floating houses can be shipyard, or factory, built instead of built on site, which is significant saving, including a saving of resources, and that you never need to demolish a viable floating-house because you need the plot for another building, which happens very often with classic houses. If you need the “plot” for another floating house, the existing one only needs to be relocated, which should not be a big worry, and it will most probably still be used at its new location. For those reasons and considering the durability of canal boats (many are more than 120 years old…), there are good arguments to consider that their complete environmental impact, including life-cycle’s, is often lower than equivalent classic houses’.

I won’t try to make detailed comparisons between Nordhavn, A40 and converted canal-boats, I understand that operating range of converted canal-boats is generally much lower, but there are exceptions. My point is mainly to say that if we don’t stick to established standards of boat-types, it looks quite feasible to built boats somewhere in between Nordhavn trawlers, A40 and converted canal-boats, keeping the best qualities of each of those categories : long range, comfort, resources consumption etc…..


Agreed about comparing Diesel Ducks since they are far more “attainable” meaning they are cheaper to buy and cheaper to operate compared to a Nordhavn. The Duck owner’s blogs I have read mentions a fuel burn of about 2 to 4 MPG. for a 51 foot LOD boat. The lower MPG is when going against current, winds and 30 foot seas. Some owners report better fuel burn with sail assist which is great but the more meaningful number is the 2-4 MPG.

The problem with many of the smaller Nordhavn’s is the amount of boat above the water line. While stability might not be an issue, the boat’s height certainly adds windage and any movement of the boat will increase as you climb higher in the condo boat.

I don’t know what a Nordhavn costs new, I have only seen used prices, but it looks like I can buy a new Duck from China for half the price of a 10 year old Nordhavn. The Duck has a steel hull which is even better and does not have a huge above water structure, even with a fly bridge. There are various LOA sized Ducks in smaller sizes that make getting a boat more attainable/affordable/possible. I look at Nordhavn’ and Dashew’s boats as unattainable for us and many people.


You mention “Diesel Ducks since they are far more “attainable” meaning they are cheaper to buy and cheaper to operate” – but my impression of these (and I may be wrong) but because they are all verging on the “custom” classification of boats I suspect that they don’t hold their value. I’ve seen some comments (I believe here) that they take years to sell, if they do – in effect confirming my bias that they are perceived as custom boats and all the value destruction that implies (i.e. heavy depreciation because they are basically prototypes in terms of each build, even though the designer might be the same person).

Also – these boats really don’t satisfy the stated goal you’ve made before that you don’t want to sacrifice anything to speed when you go to power.


So far the Seahorse Ducks seem to be holding their value. There are Ducks made by other companies that are not holding their value, primarily I think because they cost so much to build in the first place and the builder is no longer building the boats.

There is one SHM Duck, and it really is not a Duck, that is having trouble selling because it was highly customized by the owner and he left out the more desirable Duck traits. The boat has no sail, limited tanks, 900 gallons I think, in a 55 foot boat vs 2,000 gallons in the 46 foot boats, no paravanes, and no swim step. The boat also seems to be over powered and has about 100 hours on the engine in a boat that is around 7 years old.

Seahorse Ducks are not custom boats. SHM does allow the owner to specify and change some things but you aren’t going to really change the hull or superstructure on a 462 or 382 DD. The interior can be modified within reason but that is about it.

Jay Kerr

While I enjoy reading your articles very much, let’s get real about “attainable”. For most, a boat such as a Nordhaven of any size is far beyond attainable, either in purchase price or maintainence/fuel burn. For me attainable is my beloved 1979 Tartan 37 fin keel. Granted, she may not be the boat for high-lat passagemaking, but she’ll give me many years of coastal/offshore adventures here in my cruising ground in the Pacific Northwest, at a blue-collar attainable cost, and a .6 gph fuel burn at hull speed.


I really appreciate this series of posts as it helps me crystallize my own thinking. A few questions…

1. Do you normally just cruise as a couple – just the two of you? And how much does this drive your thinking in terms of the size of the boat? If you want a boat that easily accommodates two younger children, or two older parents – how would that factor in to your space requirements?

2. What about storage requirements in any power boat you purchase – for everything from food, to kayaks for cruising, to Tenders/dinks, etc. I wonder if the long-thin designs (like the Artnautica design) can accommodate the typical storage requirements that you might have for longer distance cruising with more than 2 people. Have you looked at this?

Lastly – looking at Mark Fitzgerald’s designs – I saw this design – do you know any of the backstory to it? Very intersting:


Re. storage & load carrying capacity:

The amount of stuff you can fit on the boat depends on displacement. If we take Morgan’s Cloud (25 t) and subtract the ballast, we get about a 15 tonne powerboat – and, indeed, 15 tonne motoryachts have about the same livable volume and about the same water, food and stuff capacities as MC.

Having set the size of the boat, you can then adjust the shape while keeping the size constant. If you squish the length down, you get a wide, tall “floating condo” that does well in marinas, but not on passage. Stretch it out – again, the boat’s the same size, just a different shape – and you improve performance and fuel efficiency, at the cost of taking up a lot more billable space on the pier. But it’s the same amount of boat, for the same amount of money (assuming similar build quality).


Re. Mark Fitz’s “ZIP boat”:
The idea behind shapes like this (it’s not the only one) is to (a) reduce or eliminate wave drag, and (b) minimize the waterplane area, thus making the boat somewhat immune to waves. They sort-of kind-of work some of the time, but there are good reasons why they’re rare. (A story for another day.)


Hi Matt,

I’m familiar with SWATH designs – but I’ve never seen one with a single propulsion unit like this design:

I’m wondering if anyone has ever made something like this, and what the unique benefits of this specific design are.

John – any idea?

Dick Stevenson

Dear John,
I wish to add, (in part because I am tired of hearing the belief -especially from Americans- that Nordhavens are the end all and be all of offshore passage making), that there are beautiful designs, much smaller, doing, and having done, circumnavigations. My friend Phil Heaney, designed and built Argos and took it around the world. It is a boat I believe any sailor would be pleased to be seen aboard or to own. I have limited internet, although someone with good access can get Phil’s actual site and a wealth of additional details. Argos would also make an absolutely stunning coastal cruiser with an interior that feels more like the Brilliant or a Concordia (fine furniture) than a condominium.
My best, Dick Stevenson, s/v Alchemy



The Argos looks like a nice boat – but when I look at that web page you provided a link to it states “Argos, the boat they designed, built and crewed themselves.” – and when I see that I go running in the opposite direction.

As many have said before – custom boats are the biggest value destruction activity in boats that you can find (short of sinking).

I think that one of the key requirement for any boat is that it has to have a decent value maintenance model/history – and only production boats have that.

Also – I don’t know if you’ve every been involved in manufacturing anything – but having worked in high-tech product development and production for many years (hardware and software) I know that you never want to buy version 1.0 of anything. And – the more time and unit numbers sold – the better the product gets (more reliable, bugs fixed, etc) because every product has rolling design updates and the manufacturing learning curve that every organization goes through – improves the quality of the product.


I understand that this approach is referred to as “fordism” in reference to Henry Ford’s T-Model cars (1908), but that it is probably unjust, because Samuel Colt already used extensively that approach in the manufacturing of firearms in the 1850′. It seems he had borrowed that from the manufacture of weaving machines in the 1830’….

In 2014, it looks like economics is somewhat disturbed by unclear reasons, but I understand that the undiscuted beliefs of bankers that 1830′ innovations must be the future of world’s industry is very likely one of those reasons, and I guess a significant one….



I think the concept is generally captured in two things:

1. The Learning Curve – the more that a given person/group of people do something (build something, with a feedback loop from the actual users) the better it gets, and the better the people get at producing things.

2. Economies of Scale – the more you build of a specific item, the cheaper each unit gets (and the higher reliability).

It is because of these two general rules of manufacturing – that custom boats don’t keep their value, and why production boats are generally a much better investment (all things being equal).


Economy of scale has been a very effective recipe of economic growth from say #1830 to #1995. Personally, I understand that current economic troubles are pretty much tied to a lack of pertinence of supply, that is to say that current product and service offering have become too different from real customer’s needs. This kind of discrepancy has created a loss of value of economic production and a crisis because economic actors have lost much of their appetite for those not-appropriate-enough products and services.
One of the reasons why those products and services are not-appropriate-enough is because, for the last 15 years or so, many bankers have constrained industrialist to look for economies of scale instead of pertinence of their products, because this was the recipe that did work in the 1830-1995 period. It is a known marketing bias : an idea that has been long revered and applied gains value as time passes, because it has been revered and successfully applied for so long. Let the bankers run the economy and they will worship innovations dating from #184 years ago and hate innovations of 2014…

Learning curve is not tied to fordism. A company building only, or mainly, one-off boats also benefits from learning curve (for instance Huysman shipyard…).


Hi John,
I’m curious how many sister ships to Morgan’s Cloud were built compared to your previous LeCompte Fastnet 45? (production run of 19) One was nothing but trouble and the other has been the right boat for you for years of challenging voyages. Which one is closest to a custom boat?

In theory production boats should be more highly refined, better thought out, and improve during their production run. What I see instead are boats with no sea berths or storage, deck salons so wide open that you don’t dare try to go forward when the boat is heeled, huge dance floor cockpits, and an interior structure consisting of a chopper gun pop-in liner bonded in with sticky-poo with a mast step stuck on top. Got to cut those costs down to make room for the ad agency and the dealer’s profit margin—.


No size limit on the conviction rich people have that they can have everything their whim might conceive of! Remember Jim Clark’s computerized sloop with the mast so tall that it wouldn’t go under the San Francisco bridge? The one that ran aground because the computer couldn’t sail it properly?

While building the 112′ S & S “Venturosa” we had to cut the deck apart to install a third 70kw generator to go with the two 7okw’s already in place because the owner ran out of power capacity for all the equipment he wanted. And when finally completed it didn’t have enough storage room left for the toilet paper necessary for a week cruise.

Aren’t humans a strange species? LOL



I would argue the the learning curve is really much more relevant to the discussion of passage making boats – than economies of scale.

The key point, I think is one of iterative design tweaks with significant input from end users and testing that result in a much better product for the end user. In Effect – what each boat of the same production is really a new generation of product – with all the benefits that come with iteration and thoughtful improvement to the design.

Just look at the iterative design that has taken place with the Dashew FPB and you can see this at work. FPB #1 is very different from FPB #12. I would be much more interested in #12 than the prototype #1.

FPB #1:

FPB #12 (I think thats the number):


I understand that Steve Dashew approach of boat building is pretty much non-fordian, because : he promotes boats that are significantly different from established boat types, his volumes are limited, and I understand that his designs are still evolving over time.
The whole discussion started from the differences between custom and production boats.
Point is that custom boats are supposed to be more appropriate to customers needs (provided there is no mistake..), and production boats are supposed to be cheaper, because their manufacturing is more, or much more, efficient (provided builder is efficient…). Problem is that production boats might be very inappropriate for the needs of customers who are significantly different from the average, and the right choice for them might be to commission the development of a custom boat that fits their needs, event if it is expensive. Otherwise they can buy a production boat that doesn’t really correspond to their atypical needs and accept that because of the investment savings.
Once more, it is a matter of compromises, but I do believe that custom boats have a bright future because series are made for the “average” customer, and because 1 to 5% of customers are typically too different from the average to be satisfied by series. Apart from new boats manufacturing, people who have needs that are significantly different from average can sometime obtain real bargains, because they are interested by things that don’t interest many others and that can be sold pretty cheap because of that.
Speaking of Steve Dashew, I understand that FPB#1 was 100% a custom boat that did not even belong to any established boat types.


John, There are other cruising boats aside from Nordhavn. Your article seems to assume that their characteristics are the norm for offshore displacement trawlers. Not the case. I own a Kadey Krogen 39, which is only 17 tons, and burns only about 1 gallon per hour at 6 knots. That comes a lot closer to solving your red text at the end of the article.
On a separate issue, contrary to your experience on the Nordhavn, my Kadey Krogen tracks very well.

Scott Flanders

Boat building is evolutionary, not revolutionary. I spent my working years in the marine field. My job for those years took me into boat builders and boat yards daily. The last years before retirement in addition we co-owned a boat building company. Hull #1 was as good a boat we could build regardless of cost on that day. Ten boats later they were better and so on for 250 builds during these years.

A hull #1 is always a hull #1. It isn’t the glass, aluminum or steel that fails, it is the systems that most often stops boats. Simple things. Building thru evolution makes for a better boat WAY and a more cost efficient build.

In our personal case , we talked to a well known marine architect who was also a customer. To make a long story short it would take 12,500 labor hours based on 200 new builds to build what we wanted. Boat building labor at the time cost us between $30 and $33 USD per hour to put an employee on the floor during the 90’s. It’s pretty simple math and even with labor at my cost and OEM pricing on parts the build cost was light years beyond our budget. And we would have had a hull #1.

In the end we bought hull #74 of a certain model. With that we got a fine tuned model and a Back End when it is time rather than the financial thrashing of building a one-off, one persons dreamboat.



Nowaday, higher-bracket shipyards like Huisman or Garcia are mainly building one-offs and seem to have a good stream of customers for that.
I understand that corresponding boats are made of aluminum, which is much more appropriate to small series or one-off than composite (no molds..), and that those boats are pretty expensive, especially those of Huisman, but, in France today you can find shipyards like Dujardin who accept to build one-off aluminum hulls at competitive prices.

The cost efficiency of those construction and the reliability of boat systems is tied to the capability of corresponding shipyards to gain from the experience acquired while building similar boats, that is same type of construction and systems, but not series boats.

One-off building can only make economic sense if customer’s requirements are very different from average, and if existing series boat can not fulfill those requirements for that reason. In other cases it is very likely an expensive pleasure, but I understand that yacht-owning is often regarded as an expensive pleasure, whatever the yacht….

Dick Stevenson

Dear Brian & John,
I should have been clearer as I in no way was writing to suggest that anyone should do a custom boat (and I wholeheartedly concur with the comments you both make ). My wish was to point out that ocean crossing, world-circling motor vessels need not exclusively look like Nordhavens nor do they have to be the price of a Daschew. Maybe everyone knows that, but the discussions seem to center on Nordhavens as defining the territory. I suspect there are really just too few owners who wish to be cross oceans on a motor vessel to generate much interest in this area. Therefore it remains an expensive nook.
Dick Stevenson, s/v Alchemy



You mentioned ” I suspect there are really just too few owners who wish to be cross oceans on a motor vessel to generate much interest in this area.”

Its easy to draw this conclusion if you just look at power boats – there are perhaps a few hundred (total) in terms of passagemaker power boats that actually have cruised across oceans (i.e. private powerboats under 80 feet or so, designed for long distance cruising).

But – I’ve read that on any given year there are typically 4,000 to 5,000 sailers out doing long distance blue water cruising across oceans. So – the demand is actually there – its just that most people find that sail boats are the preferred , or most cost-effective approach to that.

If boats like the Artnautica 58 can bring the cost of power and speed down to the same level as similar sail boats – then you might see a significant growth of the market, it seems to me.

Bill Balme

We think we’ve already found our next vehicle after we retire Toodle-oo! – a European barge – to cruise through the extensive European waterways – adventuring of perhaps a different type, but relevant nonetheless.
Regrettably doesn’t answer the environmental issues, but it’s a smaller footprint than a house.


Good on ya, Bill.
Houses are just boats that have run aground—.

Svein Lamark

Hi John, thanks, two very interesting posts with a high quality level and good following debates. It is nice be a reader of AAC.



Just a few quick question:

A few questions…

1. Do you normally just cruise as a couple – just the two of you? And how much does this drive your thinking in terms of the size of the boat? If you want a boat that easily accommodates two younger children, or two older parents – how would that factor in to your space requirements?

2. What about storage requirements in any power boat you purchase – for everything from food, to kayaks for cruising, to Tenders/dinks, etc. I wonder if the long-thin designs (like the Artnautica 58 design) can accommodate the typical storage requirements that you might have for longer distance cruising with more than 2 people. Have you looked at this? Or are you thinking that the Artnautica 58 design could be easily tweaked to accommodate things like this – either by being a little longer, or other relatively minor tweaks.

One other related question. At what point (if you’re modifying an existing design) is it generally considered a “custom boat”. You mentioned in your previous assessment of the Artnautica 58 that you shouldn’t “focus on the specifics” but rather the generalities. of the design. Was this because its just still in flux as an early design, or because you see the ability for people to adjust the basic design (since its in Aluminum) to suit their needs?

Dick Stevenson

Brian, You may be right, especially if the ocean crossing motor vessel brings the kind of comfort that John was describing. Dick



I like your ideas around “going light.. go solar,… wind generators…” – I think those are all pretty well-proven and effective approaches.

I also like your kite idea – there are a number of companies producing kites now, but I’ve not seen much information about their actual use by long range cruisers – has anyone got any info on this type of implementation?

Here is one company doing it:

I don’t think you want to go “electric” or “hybrid” because those are pretty complex technologies that still don’t have the reliability of a simple proven diesel design.

I also prefer the longer, thinner monohull over a cat because they tend to be shorter in design thus issues with pitching in large waves, the weight and cabin designs tends to be higher thus more windage. I’m with Steve Dashew on this one (though of course he’s talking about sail cats):

Stephen Guy


Thanks for the comments and links.

I was thinking along the lines of an Outremer or Chris White design without rig, no flybridge or high superstructure for windage.

Yes, I guess two completely independent c.50hp diesels would do the job.

I am not thinking of high latitude cruising so I realize this idea may not be in keeping with Attainable Adventure Cruising. I am of the downwind/tropical school.

Steve Guy.


My own dream (one-off…) long-range cruise-boat would be a mono-hull inspired by 1850 schooners, or 1900 Thames barges. It would use an advanced electric transmission (UQM…) for transmission-ratio optimisation, with some plug-in capacity (batteries…) using green, diesel & shore energy. It would have hydraulic power assisted winches & windlass.
Sail engine would be seriouly rethought for much longer service-life of sails & rigging. I think that much less stiff materials (including sail-cloth…) & 1850′ inspired designs could be part of the answer to that question.
Boat could be steered from a comfortable pilot house or from an external cockpit. Deck layout should allow pilot-house to be perfectly usable while not protruding too much to keep cockpit steering enjoyable.
It would be a rather large & heavy boat, built with affordable materials and a simple layout to save costs. It would use advanced computer approaches for advanced hull & sails design & optimisation.
I understand that sophisticated autopilot + fin stabiliser + vision system would be part of the equipment, probably using open-source code & hardware.
I am afraid that engineering + prototype building cost might be a bit more than 200k$….

John McIntyre

I was told by a the manager of a large marina that many of the boats kept there are only used for a few weekends a year and often leave under power and travel about twenty miles to a nearby village, kyle or cove. I’m sure the owners hope that one day they will have time free to go farther but most do not, so I found myself wondering how much fuel could be bought for the price of the mast, rigging and keel and how far could you go with that fuel.

Estimate of the cost of the rig for a 30 foot grp sailing boat.

Item Cost
Sails £5000
Rigging £2000
Roller furling gear £1300
Winches £3500
Mast £3000
Blocks, sheets, running rigging etc. £1500
Sail covers £500
Spinnaker pole £400
Keel ??
Total £17200

There are two ways to calculate the value of this money.

1. Using the exchange rate of 0.5kg CO2/£ gives a minimum carbon cost of 8600 kg CO2, equivalent to 12061 litres of diesel, which is enough to steam 24122 nm Assuming that the boats engine uses fuel at the rate of 3 litres/hour at 6 knots. If the boat dose 500 nm a year then not buying the sailing rig and travelling under power buys enough fuel for 48 years of cruising.

2. If all of the money is used to buy red diesel at 73ppl (February 2014) then you get 23,561 litres for your money, giving a range of 47,000 nm which will give 95 years of cruising or take you twice round the earth.

I conclude that an efficient power boat, either a modified yacht or a purpose designed LDL power boat, might be greener than a sailing boat.

It is often suggested that in a green economy renewable energy could be stored in batteries and used in an electric drive. However attractive as an electric boat might seem, until battery capacities increase and prices drop this form of low/zero carbon power is impractical and too expensive, which as explained already means that it in fact has a high carbon cost and is not green at all. But there may be an alternative, several pilot projects are using renewable energy to make natural gas or ammonia which is then stored and can be used as a green fuel in modified engines.


Yacht market is very complex, and it is obvious that many customers buy dreams instead of functions, so it should not be a big surprise to find out that those customers are not making rational choices, either on economic grounds or on environmental grounds.

This point being clear, I am bit doubtfull of a “demonstration” that vindicates current irrational choices of mainstream sailing-boat buyers because those choices are less rational, and less environmental-friendly, than would be perfectly rational motor-boats that in fact don’t have any real market position as of today, even if they can/could be built as one’s off (apples and oranges….).

My position is that you should compare average sailing-boats as sold on today’s market with average motor-boat idem, or, perhaps would-be perfectly rational sailing-boats vs. would-be perfectly rational motor-boats, considering that neither of them really exist in a commercial sense in today’s market.

In that case, I don’t think that today’s (irrational) mainstream sailing-boats buyers are in any way “worse” than today’s (irrational) mainstream motor-boats buyers, in economical or environmental sense.

I understand that the main difference between both is that “rational” moto- boats are supposed to exist in a technical sense, even if they don’t really exist today in a commercial sense (take a sailboat and get rid of mast & keel…), while rational sail-boat are not. Point is that nothing prevents you from building the prototype of a wooden sailing-boat with long-lasting low-stiffness sail-engine quote the would-be high-volume production costs instead of the prototype’s costs.

I guess that this boat would be a better choice than your “rational” motor-boat.

Joseph P Dillard

I am a new subscriber and sailor, but in between boats, and wanting to do some arctic exploration, thinking of a Northwest passage trip . We are based in the Pacific Northwest where sailors do a lot of motoring.

I have been searching for an acceptable high latitude vessel and stumbled upon the venerable Shannon, known for it’s quality build and iconoclastic designer, Walt Shulz. He designed and built several, 10 or so, HPS models that are supplied with a mizzen mast and twin engine redundancy. There are several interesting you-tubes where the designer is explaining his theory. They are worth looking at.

The asking price on the used market is in the range of the N55’s, which we are also considering. I think it will be a few more years before the FPB’s come in reach of even moderately wealthy people, but I see there are several on the market now.

I contacted a current owner and asked about fuel burn: this is the excerpt from his response:

“Twin Yanmar 110 HP

6.8 knots – one engine – 2300 – 2.5GPH
8.2 knots – two engines – 2100 RPM – 4GPH
9 knots – two engines – 2400-2500 RPM 6-7GPH (I don’t run this much as it only saves about 10 minutes in an 8 hour day over the 8.2 knots)”

The boat has 600 gallon tanks, so going slow with one engine pushed the range to 2500 miles, yet the boat has the potential for speed, if you want to pay the price.

Regarding the stability curves, one can review them on the specs on the above website. They are very sail-boat like.

I am intrigued by the possibilities of this boat. Might this be an answer to the question of going over to the dark side while still being able to sail when the condition dictate? I spoke with the owner and he was very enthusiastic about the boat, and said he’d transitioned from a Discovery 56 and never regretted the decision.

I love the site.

Eric Klem

Hi Joseph,

I have never been aboard one of the HPS’s but there is one out of Gloucester, Massachusetts that I see underway from time to time although almost never sailing. It is certainly capable of motoring quite quickly and seems to generally move nicely. I find that the stern looks really strange to me and I wonder how the boat would do if a wave came aboard. As John mentioned, Shannon built good boats and hopefully this model held true to that. I believe that they are fiberglass though which would be less forgiving in remote regions.

The real reason that I am replying is related to the fuel burn numbers. While these numbers are touted as good, I actually find them rather disappointing. When I saw them, I realized that they are actually quite similar to those of the schooner American Eagle from Maine which is much bigger at 92′ on deck, almost 300,000 lbs, has a full keel and a feathering prop. 6 knots is pretty safely under 2.5 gal/hr on that boat and fuel consumption stays reasonable if you don’t push it too much. Also interesting to note is that it has a single 192 hp engine which is very appropriate in size for the type of work they do but would be underpowered if really trying to make ground into nasty weather (note, they can’t quite hit hullspeed).


Joseph P Dillard

I believe they are accurate numbers, and were provided by the owner based on his experience.

This link is to the Yanmar website, and shows fuel burn data if you scroll down to the second page.

Lee Corwin

Like Bill Balm had an Outbound 46 built for us and spent a delightful decade going back and forth mostly between the Windwards and New England. Unfortunately while on the hard wife fell off her breaking her ankle in 3 places. Although she healed well her balance rearmed a bit off so unsafe on the foredeck. There went the secondary love off of my life. I started to search for a Nordie. My cruising friends said “wrong hove done enough blue. Try skinnier water. Get a SD hull”. Eventually we got a Nordic Tug 42 with a SeaKeeper.
this is a different world. No appendages except the rudder behind the keel. Operate at displayed speed or up to 17kts if you can accept the fuel bill. Ignore tides and currents if you want. Make the most of weather windows.
Unlike full displacement boats semi displacement has several tricks up their sleeves. Once you aren’t limited by hull speed you can modify the amount of pitching by varying your throttle. The SeaKeeper gets rid of roll. Throttle control can keep you on the back of a wave slightly bow up and decrease pitch remarkably. In bigger stuff Allard Coles old teaching still works. Here again having 540hp at your disposal instead of 90hp as on an Outbound makes things different. You always have more power and you can accelerate more rapidly. Rarely if ever are you at WOT. Full displacement boats don’t have these tools.
still it’s a “B” not a “A” boat so weather is looked at differently.
if we were to go back to a BWB it would be a Artnautica 58 with twin JDs. Agree with your revisions