Fuel consumption: sail/motor. are you serious?!

[Cheechako]

I did a lot of testing on planing motorboats in the 23-26 ft range about 15 years ago. With a 250HP outboard, regardless of make, they burn in the 13-14 gph range at a comfortable planing speed, but not wide open. (gas) So at maybe 26-30 mph . That's about a half gallon fuel per mile.

I don't really know why sailboats conserve fuel so well. I had a little 32 ft trawler for a while and it burned about twice as much as my 44 ft sailboat did, at a bit slower speed. The Trawler burned about 1-1/8 - 1- 1/4 gal per hour diesel and would do maybe 7-7.5 knots. The 44 ft sailboat burned .65 gallons average per hour for the life of my ownership. It would readily do 8 -8.5 knots

So in very rough terms:
In the sailboat: Traveling 80 miles will take 10 hours and use say 7.5 gallons of diesel. (using .75 gal/per hour) or about $38 of diesel.

In a planing small boat:
At 28 MPH traveling 80 miles will use about 39 gallons of gas. At say $5 a gallon the trip cost you $195

[mvweebles]

I delivered a Willard 40 displacement trawler from Long Beach CA to La Paz MX, approx 1000 nms. Averaged 7.5 kts and burned 1.4 gph GPH. A similar LWL sailboat would do about the same - laws of physics apply equally to both. I think sailors claim fantastic fuel burn because they typically don't motor long distances.

[Shanachie]

I see a lot of powerboats around western Florida with four large outboards -- maybe 300 hp each -- roaring along waterways and bays.


Yamaha says a 300 hp outboard should burn 26 gallons of gas per hour at WOT. At current marina prices, that would be about $500 an hour. Wow. Real world, I understand that number can reach 40 gallons an hour. Wow wow.



Sailboats use so little fuel because they are designed to glide through the water with little resistance.



With my Catalina 320, I routinely put the diesel in neutral 300 yards from my slip, going less than 3 knots, and make it effortlessly into my slip. I even have to put it in reverse at the last moment.

[Nautes]

Another reason I prefer a sailboat.

[HeinSdL]

Originally Posted by mvweebles

I delivered a Willard 40 displacement trawler from Long Beach CA to La Paz MX, approx 1000 nms. Averaged 7.5 kts and burned 1.4 gph GPH. A similar LWL sailboat would do about the same - laws of physics apply equally to both. I think sailors claim fantastic fuel burn because they typically don't motor long distances.

3.3 liters/minute which I think is 1 GPH. No claiming or boasting, just what I write down in my (engine) logbook. Cruising speed for my boat is about 7.5 knots.

Most energy goes into the production of waves. A Willard 40 going along at 7.5 knots I would imagine is a comfy speed not producing a lot of waves. So 1.4 GPH seems reasonable just like my 1 GPH. But push the Willard to 10 knots (possible?) and fuel burn will rise considerably. Same for my X (not possible motoring in fact). The boats reach hull speed and all that happens in excess of that = larger waves and higher fuel burn, little increase in speed.

[MicHughV]

My dad used to tell me

"son, you get nothing for nothing, and very little for money "

[Statistical]

Originally Posted by mvweebles

I delivered a Willard 40 displacement trawler from Long Beach CA to La Paz MX, approx 1000 nms. Averaged 7.5 kts and burned 1.4 gph GPH. A similar LWL sailboat would do about the same - laws of physics apply equally to both. I think sailors claim fantastic fuel burn because they typically don't motor long distances.

Sailboat with same beam, draft, displacement, and air draft as well as LWL should have similar fuel consumptions.

LWL alone isn't the whole picture. A willard 40 I believe displaces 30,000 lbs which most 40 ft sailing yachts would not. It also has significant air draft creating more drag to overcome.

However yes if there was a 40ft pilothouse sailboat that displaced 30,000 lbs then yeah i agree it probably would burn a similar 1.4 gph @ 7.5 knots.

[desodave]

Pretty consistent sailboat numbers here. We get 3.4litres/hr ( approx 0.9 USG/hr) consumption on a 40hp Volvo with saildrive in a 42ft sailboat with a usual cruising speed under motor of approx 7knots. Our boat weighs approx 24,000 lbs dry.

[mvweebles]

Originally Posted by desodave

Pretty consistent sailboat numbers here. We get 3.4litres/hr ( approx 0.9 USG/hr) consumption on a 40hp Volvo with saildrive in a 42ft sailboat with a usual cruising speed under motor of approx 7knots. Our boat weighs approx 24,000 lbs dry.

A sistership to my Willard 36 trawler went from Long Beach to Hawaii and burned something like 335 gals diesel. He averaged just over 6-kts and burned 0.9gph for the trip.

Originally Posted by Shanachie

I see a lot of powerboats around western Florida with four large outboards -- maybe 300 hp each -- roaring along waterways and bays. Yamaha says a 300 hp outboard should burn 26 gallons of gas per hour at WOT. At current marina prices, that would be about $500 an hour. Wow. Real world, I understand that number can reach 40 gallons an hour. Wow wow.

Quad 300's will easily go well over 80 mph at a gentle cruise speed. No idea how fast at WOT. So probably 80 gph @ 75-80 mph. $400/hr gets you 60+ nms offshore in an hour. Not bad value if you think about what it would take a sailboat to go that distance.

I don't understand sailors. Whenever topic of guel consumption comes up someone pipes in with outboards or massive diesels burning a LOT of fuel. As if that's apples to apples. No matter how many times someone with experience with displacement trawlers reminds them that the fuel burn difference is negligible (and the noise and comfort of a trawler significantly better than a sailboat under power), they always return to chest-thumping comparisons of the far end of powerboats. I guess it's just a matter of making yourselves feel better about sweating your butts off in the hot Florida sun (or freezing them in the cold PNW).

Sailors always assume the wind is free, sails are free, rigging is free. If I remember correctly, the first foiling America's Cup in San Francisco (2013) had Larry Ellison spending something like $100m for a boat that would do 60-kts. I was on a 24-foot center console yesterday with a Yamaha 150 which easily did 40-kts while burning 20gph. $100/hr for 40 kts doesn't seem so bad; especially when you consider it would take a sailboat the better part of a day to go 40-nms.

I think it was Thoreau who said "Everything is walking distance if you have enough time." For folks who want to go fishing offshore for a day, a sailboat is a really lousy idea. I just don't understand why sailors constantly compare themselves to that type of boat.

[Knotical]

A fuel efficient trawler will burn more or less the same amount of fuel as a comparable sailboat, maybe slightly more, if the trawler travels at the same speed as the sailboat - so the sailboat will end up being more expensive if one considers the cost of sails, rigging, maintenance etc.

A fast powerboat will burn a lot more than a trawler or a sailboat but arrive much faster at its destination.

Horses for courses 😊

I once saw a video of a guy who went from MA to FL on a new-to-him powerboat and spent something like 14k on fuel.

[mvweebles]

TCO of one Sailboat and three Powerboats. All in the 40-foot range. Costs are projected 10-year costs of 3000nm/yr cruising, which should greatly favor the sailboat. Engine rebuild factored in, as are sails and rigging. Sail assumes it motors 25% of the time. Slow trawler is assumed to be about 7% less fuel efficient than the sailboat; but sail is assumed to be slightly slower on average due to VMG issues when sailing. Fast trawler (18kts) has fewer oil changes (150 hour) but a LOT more fuel. Also, because the engines are larger,

Sail and Displacement trawler costs are roughly the same (trawler 4% higher). Cruising costs assume a fairly modest number for an average cruiser. Clearly, if you want to anchor-out and don't mind baggy sails, you can save a LOT of money. If you want to go ultra-cheap, sailboat is the way to go. If you want to cross an ocean, sailboat is the way to go. For everything else, it's a choice.

Power Costs.jpg Views: 142 Size: 85.8 KB ID: 276545" style="margin: 2px" />

[Shanachie]

Originally Posted by mvweebles

\
Quad 300's will easily go well over 80 mph at a gentle cruise speed. No idea how fast at WOT. So probably 80 gph @ 75-80 mph. $400/hr gets you 60+ nms offshore in an hour. Not bad value if you think about what it would take a sailboat to go that distance.

$400 an hour out and $400 an hour back. I don't see the value in that. I can buy a hell of a lot of fresh fish for $800.

[Adelie]

Originally Posted by Cheechako

....

I don't really know why sailboats conserve fuel so well. I had a little 32 ft trawler for a while and it burned about twice as much as my 44 ft sailboat did, at a bit slower speed. The Trawler burned about 1-1/8 - 1- 1/4 gal per hour diesel and would do maybe 7-7.5 knots. The 44 ft sailboat burned .65 gallons average per hour for the life of my ownership. It would readily do 8 -8.5 knots....

Wind is a relatively low energy source of power. Consequently sailboats are designed for low drag to compensate. This is at the expense of living volume for the same length of vessel.

[Adelie]

Originally Posted by mvweebles

A sistership to my Willard 36 trawler went from Long Beach to Hawaii and burned something like 335 gals diesel. He averaged just over 6-kts and burned 0.9gph for the trip.



Quad 300's will easily go well over 80 mph at a gentle cruise speed. No idea how fast at WOT. So probably 80 gph @ 75-80 mph. $400/hr gets you 60+ nms offshore in an hour. Not bad value if you think about what it would take a sailboat to go that distance.

I don't understand sailors. Whenever topic of guel consumption comes up someone pipes in with outboards or massive diesels burning a LOT of fuel. As if that's apples to apples. No matter how many times someone with experience with displacement trawlers reminds them that the fuel burn difference is negligible (and the noise and comfort of a trawler significantly better than a sailboat under power), they always return to chest-thumping comparisons of the far end of powerboats. I guess it's just a matter of making yourselves feel better about sweating your butts off in the hot Florida sun (or freezing them in the cold PNW).

Sailors always assume the wind is free, sails are free, rigging is free. If I remember correctly, the first foiling America's Cup in San Francisco (2013) had Larry Ellison spending something like $100m for a boat that would do 60-kts. I was on a 24-foot center console yesterday with a Yamaha 150 which easily did 40-kts while burning 20gph. $100/hr for 40 kts doesn't seem so bad; especially when you consider it would take a sailboat the better part of a day to go 40-nms.

I think it was Thoreau who said "Everything is walking distance if you have enough time." For folks who want to go fishing offshore for a day, a sailboat is a really lousy idea. I just don't understand why sailors constantly compare themselves to that type of boat.

For a day fishing offshore, a sailboat would not be a practical vessel, but then the folks that wanted to do that would be on a different website, like this one: https://www.thehulltruth.com/

For those that cruise, the focus of this website, the goal is to go relatively long distances and for most of us schedule is less of a concern.

For most of us money is also something that needs to be considered. No sails and rigging are not free, but they are a lot cheaper on a per mile basis than fuel.

Comparing an America's Cup foiler to a 24' center console seems misleading.

[mvweebles]

Originally Posted by Shanachie

$400 an hour out and $400 an hour back. I don't see the value in that. I can buy a hell of a lot of fresh fish for $800.

As they say "coffins don't have pockets." not my gig either. But let's be fair, folks spend outrageous money on sailboat gear too. I really doubt there are as many purists as forums like this leads to believe.