Gas v/s diesel for trawlers

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SomeSailor said:
"It would be very easy to build a hybrid boat these days (especially a trawler)."
  • Yes, but why?
  • Who would buy it?
  • It would be less energy efficient than a diesel with a gearbox unless - you equipped it with a large solar array, cruised nearer the equator and had corporate/government support.
If you have the financial means, are a blue water cruiser and really desire to get energy efficient, buy a Dashew FPB.
 
Don't think so. The power and range of electric technology for vehicles was very limiting, particularly back then. When forklifts started appearing in, IIRC, 1927, they were electric powered as were a number of cars.

But look up the history of electric vehicles and while there were a lot of example in the first decade or so in this country, the "craze" had died out by about 1920 and I think you'll find that trucks, at least not the larger ones, were never part of it in any significant numbers. The trucks used in large numbers in WWI were gasoline powered, for example.

Here's a little movie showing some examples of trucking in the first part of the 20th century. Nary an electric powered truck among them.

Early Trucks and Vehicles and Transport of World War 1 Troops - 1920s - YouTube

That a neat video. Was in a Nova documentarty on trucking that heard of electric being the primary power for trucks in the city back then. I think they said that electric was soon to be replaced by gas as the roads were improved. That blurb stuck in my head because i would have never thought elecric anything was very common back then. I used to buy batteries from a wholsaler, Hobb's Batteries, in Sacramento Ca. that had a very nice plush old car from the twenties in there show room. The story was that two sisters had owned the car since new and used it untill the forties when they last one passedd away leaving it to
Hobb's. They informed me that electric car had been very common but as time went on less and less of them were sold with the last manufacturer going out of business in the late thirties. Hobb's had been in business since before 1900 and they went out of business in about 1990 and i dont know what happeded to the car. Was so beautifully built. I'm gonna make an effort to find her and if i do i will pot info.
 
SomeSailor said:
"It would be very easy to build a hybrid boat these days (especially a trawler)."
  • Yes, but why?
  • Who would buy it?
  • It would be less energy efficient than a diesel with a gearbox unless - you equipped it with a large solar array, cruised nearer the equator and had corporate/government support.
I said easy... I meant that from a technical stand, but not a good business idea. :)



You could manage with a much smaller motor generator. With electric energy so cheap, you could fuel your boat at the docks, augment that with a large on board genset and battery bank. You would eliminate much of the redundancy we have aboard now.


It's about money and infrastructure though. Cost wouldn't work in today's world, there is no infrastructure for power out there and the ideal hull would be a long, slender, full-displacement vessel of some sort. Probably a motor-sailor at that.
 
[/LIST]I said easy... I meant that from a technical stand, but not a good business idea. :)



You could manage with a much smaller motor generator. With electric energy so cheap, you could fuel your boat at the docks, augment that with a large on board genset and battery bank. You would eliminate much of the redundancy we have aboard now.


It's about money and infrastructure though. Cost wouldn't work in today's world, there is no infrastructure for power out there and the ideal hull would be a long, slender, full-displacement vessel of some sort. Probably a motor-sailor at that.

You are both correct, but:

I may buy it for one, if it were properly designed. Keep in mind i have worked in in industries trying to clean up mans garbage culture since i stopped building hospitals in the mid 80's.

If i had the money i am sure i could engineer a marine electric propulsion systen for displacement speeds that would be very economical. And like mentioned above it would invole several tecnologies none of which have advanced to the point at which they can go solo. The technology is there and has been since the early 1900's as pointed out by others. Just with so much abundant cheap crude why bother, well untill now that is
 
It would be fun to have a trawler that could be driven for say 8-10 hours on battery and be able to run as a hybrid as well (if needed). If you could operate autonomously for a few weeks it would be cool.

These guys have a cool system. It's a serial hybrid electric.

http://regennautic.com/images/ReGen_newsletter_Oct_2010.pdf

Maybe someone will develop a generator / motor setup that replaces a transmission and could be drug as a regenerative supply, or powered to provide propulsion.

The problem is as you say though... dino fuel is way too cheap. (for now)
 
It would be fun to have a trawler that could be driven for say 8-10 hours on battery and be able to run as a hybrid as well (if needed). If you could operate autonomously for a few weeks it would be cool.

These guys have a cool system. It's a serial hybrid electric.

http://regennautic.com/images/ReGen_newsletter_Oct_2010.pdf

Maybe someone will develop a generator / motor setup that replaces a transmission and could be drug as a regenerative supply, or powered to provide propulsion.

The problem is as you say though... dino fuel is way too cheap. (for now)

not sure about this system.It sounds good but they seem to flirt around the edges makeing claims then passing them by. Like they mention a 42 gb but they finish saying their systems are for 60-120 foot vessels with no pix of the gb mentioned or links to other info I will contact them to see what the truth is. Thanks for the link

and merry christmas everyone:)
 
could be drug as a regenerative supply, or powered to provide propulsion.

Sailboats tried this but only in a gale will the loss of speed not be very bothersom

Sail at 6K and drop to 5K to charge and your speed loss is very noticable.

Only bu dragging a tiny prop has it worked , little speed loss , but little batt charge too.

No free lunch , regardless of the Washington view.
 
No free lunch , regardless of the Washington view.

Not claiming a free lunch. With twin engines, it appears they can drop off pure electric and use one diesel motor to drive the boat, the other to charge the battery bank. The screw on the dragging side is turning the electric motor backwards, adding charge to the bank as well.

Once recharged, you shut down the diesel drive and you're ready to go again on battery. With the right sized generator, and large enough battery, your range is greatly extended.

It's the theory behind every serial hybrid out there. The Chevy Volt is a serial hybrid.

The problem is in the infrastructure of charging stations and there's no money in it (much like the Chevy Volt). Chevy is losing thousands on each they sell.
 
The screw on the dragging side is turning the electric motor backwards, adding charge to the bank as well.

The dragging screw is turning because it converts energy from the relative movement of water across its blades, energy that was placed there by burning fuel in the engine that produced the boat's forward motion in the first place.

It recovers far less than the engine converted to produce that motion so it is folly to believe that regenerative power collection is anything other than a marketing scam directed at those who hope that there really is a free lunch.

That dragging screw is a drag. It is a net loss to the system - period.

As far as the movement of energy is concerned, a powerboat is always going uphill.
 
No matter how you want to look at it, unless you gather sunlight - or wind at anchor - every single BTU, calorie, Watt, or joule converted on your boat comes out of your fuel tank and every conversion "wastes" a portion of the energy available. There is no free lunch.
 
The generator on the draging screw is to REDUCE the loss ... not to recoup the loss or get someth'in for noth'in.

Having the two outbd screws IOs and just raise them when running single would make better sense. And of course equipping the ctr screw engine w a 2 speed gearbox would almost be necessary.
 
The generator on the draging screw is to REDUCE the loss ...

You can't reduce something by taking more out of it.

Thinking you are gaining something by having a trailing screw make electricity is like thinking a fan blowing on a sail will make a sailboat move.

Now, if you converted waste exhaust heat or used the turbocharger to drive a generator that would be different.
 
Which additive(s)?

I use Amsoil deisel concentrate additive now

AMSOIL Diesel Fuel Additive Concentrate
.
I used to use power service additive which all napa auto parts stores carry. About the same price but the lubricity improvement is slightly better with Amsoil. I sometimes also use a cetane booster

AMSOIL Cetane Boost Diesel Fuel Additive

any of the diesel fuel additives will keep the carbon out and help lubricate the upper valve train as well as keep the injectors clean. There is available at powerstroke.org a lab test of manyt of the common additives in which they are tested for lubricity and others things then compared against one another. I like amsoil cause if you sign up its not that expensive and in the test data it was one of the best.
You will notice that your engine will be quieter and start better running smoother with the additive. Go to napa and buy some ps additive and try it. Cheap insurance i use it in all my diesels.

one 16oz treats 80 gallons of the amsoil and costs about $5.00 at the discounted price
 
Since this is a gas vs diesel thread, what fuel or lube additives do you gasser boys use? Any algicides or non-gel stuff, or upper engine or lubricity enhancers, or carbon inhibitors? 'Ever consider the need to polish your gas, or use special filters? How about oil analysis? Anyone pre-lubeing their gassers?

I think diesel owners are more apt to 'play' with their motors. Gasser guys are likely to just run 'em till they quit.

And speaking of gassers. When my grandfather had The Florence built, she was billed as the largest gasoline powered yacht on the Atlantic Ocean.
 

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Since this is a gas vs diesel thread, what fuel or lube additives do you gasser boys use? Any algicides or non-gel stuff, or upper engine or lubricity enhancers, or carbon inhibitors? 'Ever consider the need to polish your gas, or use special filters? How about oil analysis? Anyone pre-lubeing their gassers?

I think diesel owners are more apt to 'play' with their motors. Gasser guys are likely to just run 'em till they quit.

And speaking of gassers. When my grandfather had The Florence built, she was billed as the largest gasoline powered yacht on the Atlantic Ocean.

Glad you asked!

In our twin screw Tolly I add Soltron http://www.soltron.com/index.htm and SeaFoam http://www.seafoamsales.com/ in just a little more than their recommended proportions to gas tanks. Keeps my gasoline fresh and free from contaminants and water and keeps my carbs' interiors clean. Although (in order of progression from tanks to the carbs) I check my screw on canister filters, in-line filters, and at carb cone-filters a couple times each year the gasoline remains clear and clean; I don’t find water, scum, or debris in them. Carbs perform well during idle through WOT and engines continually run strong and efficient at all levels rpm.

In our gas autos and trucks I run SeaFoam in a tank full of gas every 5,000 +/- miles.

PS: Tell us some about your grand dad's big boat?? Sounds interesting!
 
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With today's gasoline having a short shelf life before it starts to separate, leave gummy deposits in fuel systems, etc. does this pose as much of a problem in larger boats with automotive engines like Tollycrafts, Chris Crafts, etc as it does in outboard motors, lawn mowers, generators, etc?
 
Yes it does cause problems .

On the smaller IO boats most owners will attempt to run the tank as low as possible when the boat will not be used for a few weeks. The trailer folks will actually drain the tank, and use the gas in their cars.

Bigger boats usually have multiple tanks , which can be left empty , except for 1 for local travel.

This too is left as low as the owner dares , and filled enough before a days run.

In more civilized places like FL the non ethanol fuel is at many docks and gas stations.

Remember fuel (gas or diesel) is a pipeline commodity and only set for the local area at the distribution point , so satisfying "off road" customers is no problem.

Folks with gas gen sets will either use no ethanol fuel , (simply purchase fuel at the local small airport) or have set up for a 6 gal outboard tank .

They will disconnect the tank and run the noisemaker dry , and dump the fuel in a family car.

The rotten by law gas has made the Honda portable units more popular , and Sandy and other power company programed failures helps the Honda popularity.

AS gas is sold by the gallon the states will never allow real pure fuel again as the ethanol fuel delivers 10% less miles per gal, increasing the sales tax take by 10% , with no vote required for the tax extraction.
 
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With today's gasoline having a short shelf life before it starts to separate, leave gummy deposits in fuel systems, etc. does this pose as much of a problem in larger boats with automotive engines like Tollycrafts, Chris Crafts, etc as it does in outboard motors, lawn mowers, generators, etc?

Marin

Many persons have concocted their own rendition (too often fabricated, hoped for, or fancy-fied/farcified) as to what actually happens to “their” gasoline or diesel or kerosene while remaining in fuel tanks for short or extended durations. We as humans always have and always will be opinioned... of course not you and me though... or Fred either... and certainly not Eric! – LOL X 10. Of course, then there’s RT Firefly, now that’s a story on its own! Big GRIN guys – I’m just funnen!

So back to your question... this is what I’ve found (my learned experience/opinion!):

Before ethanol properties in gasoline became a widely pronounced commodity the “old fuel” compromised of primarily refined crude oils could also become bad (i.e. rancid/spoiled – when left untreated) and turn a putrid brown color while leaving layered varnish deposits upon internal gas lines and on carburetor or fuel injection parts or on gas tank sides/bottoms/fittings/valves. A great “wives tail’ was often used in describing how water got into fuel tanks (and into the fuel itself) via internal “condensation” forming due to temperature vitiations or high humidity weather conditions.

Fact of the matter... Any type of hydrocarbon fuel can have the correct additives/stabilizers added to the mixture that greatly reduces the “spoilage’ rate of said fuel and unless there has been severe contamination of the fuel (by properties other than fuel itself) even old fuel in containers can be brought back to “life” by adding enough of the correct fuel cleaners, extenders, enhancers. Regarding “water in the fuel”. First off, oil and water (i.e. fuel being refined crude oil) do not easily mix of their own volition, and no matter how hard one tries they will separate, unless special additives are introduced to organically or chemically intermix and change the actual composition of said products in relation to each other (such as Soltron and SeaFoam). So... the reason water “pools” (separate from the fuel) may be found in tank bottoms or in filter bottoms is due to water (separate from fuel) somehow being introduced into the fuel tank. Reason being that the ONLY way condensation can occur inside a tank (other than nominal humidity already in the tank’s specific air volume) is the water/moisture already being present via separate and specific introduction means. Water does not magically permeate through tank sides or hose exteriors. Therefore, to have water in a tank, it needs to have been placed into the tank by a “mechanical” means... such as; water being introduced during fill-ups via not properly tended fill-up stations’ mass-fuel tanks’ having latent water pools that may suck some water up during the filling task, and as is the most common on boats, deck level flush fuel portals that do not have correct grommets or “O” Ring seals and that sit in rain or melting snow/ice conditions for months at a time, year after year. Untold amounts of water can seep in this way, drip by drip over extended periods can add quarts or even gallons of water into boat fuel tanks.

When I take my screw on canister gasoline filters off (the first passage of fuel through my three stage filter system) and drain them into a large clean coffee can the gas is consistently pure and clean with no contaminants or water present.

Interesting personal occurrence: Months ago I purchased a 20’ direct drive, 270 hp, 350 cid Malibu Skier to restore. Boat had been at rest for some 8 +/- years. When I removed the gas tank (off white translucent/opaque plastic material that let sunlight well illuminate inside the tank) it had some 10 gals of gas. I removed the fill tube and poured a little in a glass jar. Fuel looked a bit discolored but not too bad. I could see no water or schmeg in the tank bottom as I slowly tipped it. I then added a bit of Soltron to the fuel and let it sit for several days. Then I poured the gas into a couple of 5 gal cans finding it had lightened in color and had no water in the tank at all. I poured one 5 gallon tank of that gas into a near empty tank of our fuel injected Ford Explorer and poured the other 5 gallons into my 1 ton 4WD Chevy PU with a carbed hotrod 325 hp 350 cid engine. Never had a problem with either vehicle. Now – Please do realize, that was 8 +/- year old gasoline that sat in a tank under an unheated canopy to which I simply added about 3X the recommended amount of Soltron fuel additive. In normal conditions of adding Soltron to our Tolly gasoline the cost is just a couple pennies per gallon.

So, I repeat from a previous post:

In our twin screw Tolly I add Soltron http://www.soltron.com/index.htm and SeaFoam http://www.seafoamsales.com/ in just a little more than their recommended proportions to gas tanks. Keeps my gasoline fresh and free from contaminants and water and keeps my carbs' interiors clean. Although (in order of progression from tanks to the carbs) I check my screw on canister filters, in-line filters, and at carb cone-filters a couple times each year the gasoline remains clear and clean; I don’t find water, scum, or debris in them. Carbs perform well during idle through WOT and engines continually run strong and efficient at all levels rpm.

In our gas autos and trucks I run SeaFoam in a tank full of gas every 5,000 +/- miles.
 
Rick B wrote;

"You can't reduce something by taking more out of it."

Cute Rick but as long as the prop is dragging through the water turning one may as well link it to a generator and recoup some of the loss. The loss is a given. One must drag the screw in this case so in a way (w the gen on the dead shaft) your'e get'in something for nothing. But of course there would be a tiny increase in prop drag from the reduced speed of the prop. Not enough to measure or change the scope of things.

So yes we would be reducing something (the loss of energy (drag)) and we would be taking "more" out of it as nothing would be "taken out of it" otherwise. Something rather than nothing is a gain = more.

Art,
I like SeaFoam also and have dumped LOTS of old OB gas into my 85 Suburban. I never put gas mixed w oil in my cars that have catalytic converters. Otherwise it's great upper cyl lube.
 
Cute Rick but as long as the prop is dragging through the water turning one may as well link it to a generator and recoup some of the loss. The loss is a given. One must drag the screw in this case so in a way (w the gen on the dead shaft) your'e get'in something for nothing.

You don't really believe that do you?

If you do then why don't you drag a giant waterwheel behind your boat and use it to power the shaft instead of a noisy, stinky, fuel burning engine?
 
It recovers far less than the engine converted to produce that motion so it is folly to believe that regenerative power collection is anything other than a marketing scam directed at those who hope that there really is a free lunch.

Not a free lunch. Just another method to charge that large battery bank. The motor normally used to drive the boat is now being used to charge a bank. It is working right alongside the large 100KW generator.

Here's another link to a similar idea using diesel electric / series hybrids:

Redwing Hybrid 40 - Power Cruiser/Trawler - Boat Plans - Boat Designs
 
Rick says;

"You don't really believe that do you?"

What a silly thing to say Rick. Of course I do .... That's why I said it. You need to come in out of the dark Rick. No offense of course.

Thank's SomeSailor. You didn't need to say that but you did.
 
Since this is a gas vs diesel thread, what fuel or lube additives do you gasser boys use? Any algicides or non-gel stuff, or upper engine or lubricity enhancers, or carbon inhibitors? 'Ever consider the need to polish your gas, or use special filters? How about oil analysis? Anyone pre-lubeing their gassers?

I think diesel owners are more apt to 'play' with their motors. Gasser guys are likely to just run 'em till they quit.

And speaking of gassers. When my grandfather had The Florence built, she was billed as the largest gasoline powered yacht on the Atlantic Ocean.

I use Lucas in my gassers. Lucas can be used in either and i met a guy claiming 900,000 on his 6.0 which he claimed wouldnt have hapened without lucas. I started useing it in 07 on my 6.0 then switched to amsoil when i discovered the test comparison and amsoil had better lubricity. I used to use chevrons Techron untill lucas in gasses
 
Didn't Nordhavn try a Diesel Electric some time back?

If any manufacturer has a customer base that would benefit from this supposedly great drive system and the expense of getting it right, I'd assume it to be Nordhavn.
 
Not a free lunch. Just another method to charge that large battery bank. The motor normally used to drive the boat is now being used to charge a bank. It is working right alongside the large 100KW generator.

You are talking about using an engine to charge batteries. I was talking about the fantasy that taking power from a trailing screw contitutes a means to recover power.

Not even in the same conversation.
 
Rick says;

"You don't really believe that do you?"

What a silly thing to say Rick. Of course I do .... That's why I said it. You need to come in out of the dark Rick.

No offense taken, I don't even mind the fact that there are still people who believe the Earth is flat. It all adds the entertainment value of forums such as this one.
 
If any manufacturer has a customer base that would benefit from this supposedly great drive system and the expense of getting it right, I'd assume it to be Nordhavn.

Diesel-electric propulsion is a great system, there are few who would argue otherwise.

There are, however, many good arguments against the system when it is installed in a boat which is used in an application where the benefits of D/E contribute nothing.

Recreational vessels in general and smaller recreational vessels in particular are an example of where the installation of an otherwise good technology is used inappropriately - to the detriment of the user and the vessel's reliability and economy.
 
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