Fuel economy discussion...more important now than ever!?

How many galley slaves will I need on the pedals of my 50' displacement cruiser to maintain hull speed in 8' to 10' seas? Given all the sanitary needs of such a "motor" even if I could afford to pay them, I think I would rather buy diesel instead. It would get a little crowded around the dinner table too......

I find this to be similar to the ongoing debate regarding wilderness access via foot traffic only as opposed to motorised traffic. Why should only the young and fit be able to view our natural wonders? Shouldn't taxpayers who are in less than perfect physical condition due to advancing age or disability be able to enjoy our parklands too? The same with boating, should only those able to maintain an aerobic state for an hour or so be the only ones able to get out upon the water? My mother (85) and father (91) love to cruise with us when we charter the Inside Passage on board diesel vessels. Due to balance issues they are emphatically unable to travel aboard a similar sized sailboat. BTW most sailboats up there motor most of the time anyway due to the prevailing winds. I know that the intent is not ageism, but the result sure seems to be discriminatory as far as the park access goes. (please note that I am not defending the idiots on ATV's dirtbikes and snow machines that do so much damage)

 

So, who says you would have to feed them? They are slaves, afterall. ;-)



All kidding aside, your comments in the rest of your post, point directly to the suggestion I made regarding a drive system transition period, while more efficient and less polluting propulsion is being developed.

To that end, I'd suggest a bio-diesel/electric drive system. There are already several manufacturers of really nice units that would work perfectly for a boat the size that you propose.

You will most likely have considerable surface area on the top of your cabin structure. That surface could be fitted with thin film solar units which would augment the diesel electric drive capability. Right now, there is a surface coating being developed with a solar electric capacity for power generation, so the possibilites are growing everyday.

When better systems emerge, you keep the craft and replace the components of the drive system as appropriate.

Following the existing examples of the Dashew experiences, you have a clear path to a really nice, as well as efficient, boat.

Chris

 

does anyone have a copy of woodenboat #47,,and see the (energy48 ftr)it says it uses 3quarts of fuel to travel for 10 hrs,,it is a slap .gorgeous double ender,, she is 48 ft ,,45 low,,,,8'5"beam,,and Francis Herreshoft made some nice comments about her ,,if I have to I can print the artical ,,(but ya gotta wait till I catch one of my kidds to help me do it ,,but was hoping someone else (smart person with computer skills)could do it now,,,longliner

 

That's for sure! Of course the boat I posted is not a Diablo, it is a modification that results in a really good full-displacement hull that can be built easily and inexpensively because all panels are developed and therefore suitable for flat-panel construction with glued taped seams.

By the way, it's not for offshore use, it's a day boat designed to shuttle lots of people back and forth between islands and along the coast. With ten people it may look overloaded but it's not. Besides Filipinos typically put 20 people into vehicles and vessels designed for ten, so I suspect this boat will almost always have 10+ people in it ...

 

So, who says you would have to feed them? They are slaves, afterall. ;-)

Slaves have a value , so the boat should be powered with the least valuable resource.

The Employer of Last Resort (Gov), spews many Employees of Last Resort (BuroRATS) on an annual basis .

Simply select as many as you can use on a cruise and discard as they wear out.

None are used to a real days work , but at the effort of getting 300% extra should still be a deal!!



FF

 

Speed vs economy of operation

When we speak of speed, economy of operation flies out the window with exception of wave piercing cats. For cruising, the technology has been around for a long time to combine great hydrodynamic hulls with moderate power in sailing vessels. On our 30 foot center cockpit sailing vessel, we can cruise under Yanmar (15 hp) power for four 10 hour days at 6 knots on just 16 gallons of diesel fuel. Any center cockpit sail boat can be can converted to a great cruising boat with or without mast. Building a hard cockpit enclosure enhances livability. One thing that we did to enhance engine efficiency was to replace petroleum lubricating oil with Mobile 1 synthetic oil. We have used garage refined biodiesel (used cooking oil refined) in the engine too without any adverse affects or injection modifications. Biodiesel is great for the small quantites of fuel needed for small sailing vessel engines in that a sufficient quantity can be made to last a month or more by processing for a few hours of one day.

 

Mercedes diesel

Masalai, I believe that you are refering the Mercedes BlueTek diesel that is also now used in the VW Jetta. Both Mercedes and VW should have information available on the specs and availability of their entire engine lines.

 

Fred,not all small diesels are high speed,i drive a 1996 Vw passat tdi, it has 215000 miles on it which if you average at say 40mph is over 5000hours and its still only using about a quart of oil between 7500 mile change intervals.Its about 90hp,tons of torque which it achieves at about 2000 rpm.I think two of these would be great in a power cat.It just sips fuel,i just did a 385 mile trip on just 6.9 US gallons for 55.8mpg.
Steve.

 

Wow!

Steve,

Can you recall what kind of speed you averaged to get that mileage?

Chris

 

I have a 2003 VW Jetta with the 1.9L TDI. In the summer heat I can get around 57 mpg driving real nice and mostly 65 mph on highway. All around driving summer I'd say I average 52-55 mpg, and about 48-50 in winter.

I towed a 2 person wave runner behind it on the highway to the shore doing an average of 70 mph up and down hills and got 41 mpg. The engine is rated for 90 hp @ 3750 rpm (but you rarely will ever need to rev the engine this high)

there are chips you can get that increases mileage and hp even more by creating more boost at lower rpm - of course if you are hammering on it, the chip will decrease efficiency.

 

See post 14 in this thread for a link to the VW marine diesels.

Regards

Alan

 

No....to quote the WoodenBoat piece "She cruises 10 miles in an hour on three quarts of diesel fuel."

Speed would be about 8.6 knots and almost 11.5mpg, no question this is fairly good. The Energy 48 was built (cold-molded wood) in 1979, is 45' LWL, with 8'5" of beam, she's double-ended and weighs about 10,000 pounds (reported). Power is a Westerbeke 30, producing 25 HP at 2500 Rpm, running a Hurth 2.1:1 gear and turning a 15" by 12" three bladed prop. She was designed and built by Arthur Martin, who also created the Alden Ocean Shell and the Appledore Pod, which he reportedly scaled up to make the Energy 48.

In the mid 90's I did a shorter boat (38') that burns the same amount of fuel (.75gph) to do 7.2 knots, She's called Yellow Cedar. She's got more living space than the E48, but isn't as fast. Picture below.

There was no market interest in either Martin's E48 or my Yellow Cedar.

 

And that is a shame, Tad. Hang tough, Bro, it'll come 'round on the guitar for you in short order when we'll all be singing a different tune.

Chris

 

Well.....I really wonder Chris.

The major consequence of high fuel prices is that the cost of basics like food goes way up as well. If people have less disposable income and are saddled with big payments on the Bayliner sitting in the driveway and un-marketable at any price. How would they be able to buy new (different) boats? I believe we'll see fewer new boats being built in future, that time may be past.

Today I'm thinking ways to recycle/refit what's already been built. How about bolting two Bayliners/Searays/whatevers together, transom to transom? Actually maybe cut the transoms off and glass them together, set aside the outdrives and V8's to use as a mooring, and put a couple of electric outboards under one veeberth. Batteries go midship under the cockpit, good privacy with two separate cabins.

 

Nordic, Pardon my ignorance but I can't read of speak German???