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I've been a costal cruiser for a little while. Last year on my C&C 30 (16hp), used less than 20 gallons for a year. However, as a youtube person living my life through other peoples world travels, I noted some people seem to have to fill up often and inconveniently due to small capacities.
A couple years ago looking at catamarans, I decided to make a cut off point to not look at catamarans with fuel tanks under 150 US gallons (550 liters).
Is this excessive? How much does one really need? This would be a catamaran for circumnavigation and living aboard for 10+ years. It will have a generator and cloths washer to keep my wife happy. A/C use is undetermined and will vary based on guess a few times a year.
 

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Aspiring Boat Bum
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Answer kind of depends. Based on your plans to run a generator and possibly air conditioning then definitely more is better but...

Will you be cruising remote areas with limited access to refuel?

How long would you expect to spend off the grid away from fuel supplies?

What other sources will you have to charge the house batteries?

Depending on the answers to all the above 150 gallons might be significant overkill or might be sufficient. Unless you plan on spending months in the middle of nowhere don't thing you would need more than 150 gallons.

One thing to consider, on a cat additional weight is a real performance killer. That much fuel will add over 1000 lbs to the boat. If I felt the need to carry that much fuel I would certainly split it between at least two tanks and only fill all when necessary.
 

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A couple years ago looking at catamarans, I decided to make a cut off point to not look at catamarans with fuel tanks under 150 US gallons (550 liters).
Is this excessive? How much does one really need? .
I doubt you can even buy a Cat with 150 gallons.

My boat... Which has circumnavigated... has 38 gallons in the tank and about the same in gerry cans.

Why in the world is a boat maker going to design a boat without useful tankage.

Go find a boat your wife will want to live on for 10 years and buy that. I am sure you won't even have to enquire as to the tankage.
 

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Fuel tank capacity is really a matter of Fuel availability where you are sailing and how much you have to motor.

For example in southern NE there are so many fuel docks you don't need much capacity in your tanks

Further you cruise from fuel docks the more you need to sail and the more your need to carry more fuel on board.

Like Mark's boat Shiva has about 38 gal and with a few jerry jugs fuel was never an issue. For passage I carried more jerry jugs.

But I have had to motor over a thousand miles when we found ourselves in a huge dome of high pressure with no wind. Used all the jerry jugs!
 

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bell ringer
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I have a 50 gal tank and I’m not against running the engine for 24+ hours sometimes. The lowest I’ve gotten down has been 10 gals the past 20 months. If I’m not motoring a lot I find I need to fill the 150 gal water tanks before the fuel tanks. But coming down say the ICW that switches. At cruising speed that 50 gals is over 400 miles

I do carry a 1 5-gal jug backup, because it only takes once to learn the lesson.
 

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Master Mariner
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When we sailed from Hawaii to Tahiti we had our tank fuel and a 150 gallons deck loaded. We hit the doldrums as expected, and motored through, using the deck loaded fuel. Then we hit 10 days of no wind at all. When we had burned our allotment of fuel considering the Tuomotus were still ahead, there we sat. We could smell the Marquesas as we drifted by, but there was no fuel to be had there, so that was that. But that was the rarity. Mostly the fuel tankage (around 200 gallons) was more than sufficient for a 32 ton gaff rigger.
On our present boat, we run a generator 2 to 3 hours every day and the main engine now and then. Now we average about 500 gallons a year, in 170 gallon tank, but we are a charter boat, with schedules to keep. That 170 gallons allowed me to motor from San Juan to Charleston SC one year, when here wasn't enough wind to even motorsail.
Every boat does OK under power in flat water. When the seas get up, so does fuel consumption, sometimes a lot, especially when punching to windward.
There are places like coming out of Panama going west, where it is possible to have a thousand windless miles. Most would deck load fuel for that trip, or any trip, where they expected to use more than their tanked fuel.
 

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Bombay Explorer 44
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For circumnavigation you should be able to motor at least 25% of the distance. It is better to assume 30%.
So motoring for about 8,000 miles

Assume 1 gph

That is 1,333 gallons.

Anyone know of a sub 50 ft sailboat with that sort of tankage?

BTW I have a 44 ft sailboat with a typical 70 gallon tank. 1,333 is just ludicrous.
 

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Quoting actual capacity is like asking how long is a piece of string. This really depends on the fuel consumption of the engine and generator, the likely distance to be covered and whether there is reliable wind or doldrums.

I support the idea of having the ability to motor a percent of a passage, until fuel will be available again. What percent is the skippers call.

Keep in mind that lower RPMs and speed can substantially extend endurance.
 

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For circumnavigation you should be able to motor at least 25% of the distance. It is better to assume 30%.
I also find this statement to be completely odd.
When ocean sailing, far from land, most will wait out the wind if they lose it. Fuel, in most cases on a sailboat, is for near shore situations and docking or entering strange harbors, or their generator.
Please explain why you think someone with a sailboat should need to power 30% of the time, on a circumnavigation.
 
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I think the 30% figure quoted was for between points where fuel was obtainable. So instead of 30,000 miles, 3,000 is a more likely figure and 30% of that is just under a thousand miles. We had an 800 liter capacity and were really glad when the forestay parted 500nm from port. Could have gotten by with half that capacity, but the beer would have been very warm that far south. So your 150 gallon requirement is very much in line. As stated above, you can add deck fuel if you feel more comfortable with a big reserve.
 

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BTW, philosophically speaking, I notice one of the repliers in this thread, whose circumnavigating experience was well into the early parts of last century, mentions motoring through the Doldrums (ITCZ et al)

CHEATING!!!!!!!!!!!!!!!!!!!!!!!!

One of the great wonders of the nautical world are the Doldrums. They're steeped with history of sailing adventures since time immemorial.

I have been through a few times and the only way to do it is to sail. The first time through, on someone elses boat we motored and I was devastatingly disappointed!

On my own boat I do what them old buggers had to do.

Day after day, day after day,
We stuck, nor breath nor motion;
As idle as a painted ship
Upon a painted ocean.
That is not about the Doldrums but about some bloke who shot an Albatross.


I commend ye to go sailing in the 'proper' way. Its more rewarding.
 

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For circumnavigation you should be able to motor at least 25% of the distance. It is better to assume 30%.
I have no idea what the poster possibly could be thinking, but as others have said, this bears no resemblance to a reasonable approximation of reality. But beyond that, much of the answer revolves around the choice of boat and the choice of comfort level, since that impacts fuel consumption. For example, if you are of the 'all the comforts of home' school of thought, I can't think of a sub-50 foot boat that carries enough fuel to run air conditioning for a long passage.

At the opposite end of the spectum, the "go spartan- go now" school of thought, almost no fuel is required, especially when combined with a decently performing boat. An example of that school of thought was conversations that I had with two separate owners of sisterships of my boat.

The one had sailed from Capetown S.A. to the Caribbean. That boat was equipped with a windvane for steering, did not use refrigeration, would switch in the GPS 4-5 times a day and record coordinates. ran a tri-color at night, ran the engine well less than an hour every 3-4 days to recharge the batteries and that was only in cloudy conditions when the solar panel could not keep up, and made the trip on less than 12 gallons of fuel, less than 60 gallons of water, and averaged 150 miles a day for the entire trip. That might not be viewed as a normal passage since the first 10 days was spent broad reaching and running up the coast of Africa in 30-50 knot winds. Once things lightened he angled across the South Atlantic below the Doldrums to the South American Coast where he close reached in the adiabatic winds until north of the Doldrums.

The other couple with a sistership, went non-stop from South Africa to Scotland. They used closer to 25 gallons of fuel but motored part way through the Doldrums. If I remember correctly they carried roughly 40 gallons of fuel (two 13 gallon tanks plus gerry cans on deck). In flat water, these boats will motor at roughly 6 knots at a 1/2 gallon an hour so arguably they had at max a roughly 240 mile range. They had refrigeration that used an engine driven compressor and cold plates so arguably they had less range.

I would not even conjecture what the other end of the spectrum looks like.

Jeff
 

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The premise of this thread begs a point of clarity. What are the longer distances between fuel availability for the typical circumnavigation. Assuming the outlier long legs could be accommodated by fuel jugs, what is a reasonably long leg. A couple thousand miles? Carrying fuel for 500-600nm doesn't strike me as either unusual, nor excessive.
 

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p.s. We can easily get 500nm out of our fuel and I consider our tankage to be Coastal sized. I would prefer to have much more, to be far offshore. Not necessarily to motor alot, but to run the generator and have the option to motor, if sailing would put us in danger of incoming weather.
 

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The premise of this thread begs a point of clarity. What are the longer distances between fuel availability for the typical circumnavigation. Assuming the outlier long legs could be accommodated by fuel jugs, what is a reasonably long leg. A couple thousand miles? Carrying fuel for 500-600nm doesn't strike me as either unusual, nor excessive.
The longest leg of the "normal" tropical downwind cruising circumnavigation is 3,200nms from Galapagos to Marquesas. Its pretty damn difficult to get becalmed on that passage and if you do its going to only be for a day. Mind you Fatty Goodlander just finished that passage and must have been angry at the weather gods... and had a slow passage.

Then theres a number of passages about 2,000 to 2,500 long. But they are all really in the Trade Winds areas.
The Doldrums are only 120 nm to 200nms wide so its not really going to be a difficulty anyway.

As Jeff_H shows in his post, the Atlantic isnt too bad at all if you know where you are going. The Doldrums not very wide. The Azores High is large but you go around that, dial up whatever wind you want, really.

As aeventyr60 said, theres a huge chunk of Asia thats in the Land Above the Wind and you do need to motor a fair bit... but the ranges are short and the fuel is cheap.


:)

A tropical circumnavigation just isn't that difficult. Most people over-stress about the irrelevancies (taking a wood router) instead of the important stuff (good satellite coms to download weather). I think the reason why many over-stress the irrelevancieis is that the planning phase takes years.. Job, boat buying etc, so to keep the dream alive they invent problems so they can solve them at the desk at work... and then scare the crap outta themselves. :smile Then they go home and read Survive!, watch Perfect Storm! and Adrift! and finally roll over and die like the Titanic!

(Never watch a movie or read a book with a ! in the title!

Remember, what you think is important is not. What is important can be picked up along the way.

Its just not that difficult :nerd
 

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Minne's post is very helpful. Using Mine's boat as an example, which has a comparatively large motoring range of 500 miles, and the roughly 6,000 mile passage from Capetown to Barbados or Trinidad that I mentioned above, that represents a range that is roughly 8-9% of the passage length. I suppose that it is probably possible to do a circumnavigation where the longest passages are something like 3,000 miles, which starts to get Minne's motoring range up to around 17 percent of the longest passage.

(Edit: Mark's post crossed with mine, but also sheds a lot of light on the point I was trying to raise)

Jeff
 
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