A small tale of mice, men, engines and costs ...

[pragmatist]

Since I've had lots of useful help from the forums recently on practical subjects, I thought I'd try posting something potentially more contentious We currently have an 11m sailing catamaran. Our last boat was a Rival 41 which had a 38hp engine. We feel we have lots of engine power now - two 29hp diesels. Luxury ! But in walking through Darthaven Marina I came across this Antares 11 with two 300hp outboards. We use less than 5 litres an hour cruising with both engines at about 6 knots. Apparently the Antares uses 81 litres per hour at a cruising speed of 16 knots. With current fuel prices at the barge in Dartmouth I make that about £7.50 an hour for us and £186 for the Antares, assuming we don't sail. Of course the Antares would get there 3 times faster than us but I still find that a stunning difference. Don't think we could or would afford nearly £200 per hour ! Would you ?

 

[capnsensible]

I reckon cruising costs for motor boats is just something people factor in when buying a boat. Let's face it, there are plenty of boat owners that don't want or like to sail.

I do both.

 

[Supertramp]

The real cost difference per mile is probably about 10x. But the real difference is more likely to be in the distance travelled with an outboard driven boat doing far fewer miles and hours run.

I'm sure a motorboat owner would look at rigging, sail and rope renewal as an equivalent high cost. It's easier to rationalise big spends when they can be spread over longer periods.

Annually the fuel cost is still probably less than berthing costs!

 

[johnalison]

I think you are right to be stunned, in fact, I am stunned that you are prepared to consume 5L/hr compared to my 2-2.5. More seriously, It is hard not to see price and availability of fuel taking a large dent out of powerboat usage and ownerage.

 

[Bouba]

When anyone considers getting a motorboat it’s their first question…what’s the mileage?
The advice given by the motorboat forum is always the same…don’t worry about fuel costs…that’s the least of your problems

 

[Momac]

Apparently the Antares uses 81 litres per hour at a cruising speed of 16 knots.

If it only does 16 kts with those engines and at that fuel use that would be disappointing . 16kts would in any case be an uneconomical speed .
More like 25kts or so for optimum fuel efficiency (at speed) .

 

[Stemar]

Someone in our club has a Catalac 8m with twin 70HP engines. I thought that was mad, with ridiculous fuel costs until Pragmatist's post. Friends have the same boat with a single 10HP OB, and they get around fine, though I do prefer our twin 20s, especially if we're trying to punch a spring tide back into Portsmouth Harbour. Sure the 140HP boat can go faster - almost twice our speed, but that empties his wallet around 10 times faster than us doing 6 knots.

 

[B27]

Since I've had lots of useful help from the forums recently on practical subjects, I thought I'd try posting something potentially more contentious We currently have an 11m sailing catamaran. Our last boat was a Rival 41 which had a 38hp engine. We feel we have lots of engine power now - two 29hp diesels. Luxury ! But in walking through Darthaven Marina I came across this Antares 11 with two 300hp outboards. We use less than 5 litres an hour cruising with both engines at about 6 knots. Apparently the Antares uses 81 litres per hour at a cruising speed of 16 knots. With current fuel prices at the barge in Dartmouth I make that about £7.50 an hour for us and £186 for the Antares, assuming we don't sail. Of course the Antares would get there 3 times faster than us but I still find that a stunning difference. Don't think we could or would afford nearly £200 per hour ! Would you ?

16 knots seems very slow for 81 litres an hour.

Most people with shiny power boats seem to do relatively low mileage in a year.
A typical outing for such a boat is often just a blast around the headland to the next bay, or down the coat to the next port. The owner probably uses more fuel in his car driving to the boat to sit in the marina.

 

[Dellquay13]

If it only does 16 kts with those engines and at that fuel use that would be disappointing . 16kts would in any case be an uneconomical speed .
More like 25kts or so for optimum fuel efficiency (at speed) .

If 16 kts is the lowest speed that the boat reliably holds on the plane, then that will be an economical speed. My little MoBo with 70hp 4t o/b starts planing at 12kts, holds the plane easily at 14kts and best economy 8mpg and tops out about 28kts at 4mpg.
My yacht 1gm10 sips about 1.2lph I think.

 

[LittleSister]

I was sitting in a very quiet pub in South Devon many years ago, and couldn't help but overhear the chap on the next table telling his friend about someone recently taking him out for the day in his powerboat, which was obviously a new experience for him. On return to the marina, the owner pulled in to the fuel dock. The chap speaking said he handed the owner a fiver towards the fuel, then died with embarrassment when the pump clocked up £345!

 

[Bouba]

I was sitting in a very quiet pub in South Devon many years ago, and couldn't help but overhear the chap on the next table telling his friend about someone recently taking him out for the day in his powerboat, which was obviously a new experience for him. On return to the marina, the owner pulled in to the fuel dock. The chap speaking said he handed the owner a fiver towards the fuel, then died with embarrassment when the pump clocked up £345!

In actual fact this is an etiquette problem....our friends took us on a two week cruise and my wife was upset that I didn’t contribute...but I don’t expect people to chip in for my fuel...so I was happy with my conscience

 

[LittleSister]

In actual fact this is an etiquette problem....our friends took us on a two week cruise and my wife was upset that I didn’t contribute...but I don’t expect people to chip in for my fuel...so I was happy with my conscience

In this case, I think the guest felt it would have been better - at least less embarrassing - had he offered nothing, but I think he was OK - showed willing and he wasn't to know it was such an expensive pastime. Hopefully the owner thought similarly - he probably would have spent the same had he been without his guest.

 

[fredrussell]

In actual fact this is an etiquette problem....our friends took us on a two week cruise and my wife was upset that I didn’t contribute...but I don’t expect people to chip in for my fuel...so I was happy with my conscience

Yorkshireman?

 

[Bouba]

Yorkshireman?

How dare you, sir !

 

[Dutch01527]

In actual fact this is an etiquette problem....our friends took us on a two week cruise and my wife was upset that I didn’t contribute...but I don’t expect people to chip in for my fuel...so I was happy with my conscience

What do other people do when sailing in company?

On a longish cruise I have always assumed that direct costs such as fuel and mooring are shared amongst adults. Boat costs such as breakdowns and damage are the owners responsibility. I have always paided on other peoples boats and made the assumption clear well in advance on my boat.

Is that reasonable?

 

[Bouba]

What do other people do when sailing in company?

On a longish cruise I have always assumed that direct costs such as fuel and mooring are shared amongst adults. Boat costs such as breakdowns and damage are the owners responsibility. I have always paided on other peoples boats and made the assumption clear well in advance on my boat.

Is that reasonable?

It’s called ‘going Dutch’...

 

[KevinV]

What do other people do when sailing in company?

On a longish cruise I have always assumed that direct costs such as fuel and mooring are shared amongst adults. Boat costs such as breakdowns and damage are the owners responsibility. I have always paided on other peoples boats and made the assumption clear well in advance on my boat.

Is that reasonable?

If one could afford the costs of running a boat one would own a boat (I can and do, but on a very modest scale). If I invite you on my boat you can bring a bottle and buy (or cook) me dinner.
I've always applied that principle when guesting, plus I like to be useful on board.

 

[Momac]

If 16 kts is the lowest speed that the boat reliably holds on the plane, then that will be an economical speed.

I don't agree in the case of the subject boat or others like it.

 

[Aja]

Good luck in fuelling a boat that drinks petrol any where apart from the south coast.

Watched a mobo at Oban transit marina this summer going back and forwards to the nearest petrol station with 25L cans in a marina trolley.

 

[Momac]

Good luck in fuelling a boat that drinks petrol any where apart from the south coast.

This was a reason why we bought a diesel engined boat. Lugging fuel in cans is no fun at all.
But I do see the point of outboards as they are apparently easier to service and they are tilted out of the water when the boat is not in use,