View Poll Results: Check all that apply to you.
Have never had an engine failure in my twin engine boat. 6 17.14%
Have had one or more failures that could be fixed at sea. 17 48.57%
Have had one or more failures that couldn't be fixed at sea. 16 45.71%
Have had both engines fail at the same time, getting a single to cut my failures in half. 1 2.86%
Multiple Choice Poll. Voters: 35. You may not vote on this poll

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Old 05-28-2016, 06:38 AM   #41
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Just to clarify the probabilities for failures of twins......

Let's say a single engine and drive train has an expected failure rate of once per 1000 days, i.e. 1/1000, for a failure that will disable the boat.

A twin engine boat will then have twice the failure rate, i.e. 2/1000 or 1/500. But, because you have twins, the failure is no longer disabling.

To disable the boat, you need two failures, one in each engine. That's 1/1000 times 1/1000, or 1/1,000,000.

So statistically you will have twice the number of things to repair, but you mean time to being disabled goes from 1/1000 days to 1/1,000,000 days.

Now that is ONLY looking at the engine and drive train. Other things can disable a boat too. People have mentioned the fuel system as a likely cause, and for that you need to look at the probability of "failure" of the fuel system, not the engine(s). If you want to significantly reduce the probability of a fuel system disabling you, you need to adopt some sort of day-tank approach where you quarantine new fuel, then filter it and run off some store of known-good fuel.
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Old 05-28-2016, 07:48 AM   #42
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Quote:
Originally Posted by bfloyd4445 View Post
The electric motor is more efficient than the d you have it backwards. They are conservative and state a 700nm range on the 33 because the hybrid system is an option and not standard. D engine only you get 700nm range.But if you opt for the hybrid option you have the option of running on pure electric which gives you an aditional 20nm range before batts need recharging., Takes 2.5 hours to recharge the batts via d engine alone. During the day with the sun shining you have the roof mounted 11kw solar pANELS ALSO CHARGING THE BATTERIES SO MY NUMBERS ARE CONSERVATIVE ALSO BECAUSE I DIDNT FACTOR IN THE SOLAR INPUT JUST USED THE FACTORy NUMBERS FOR engine generator charging. opps cap lock. sorry I wasnt shouting on most of my computers i have removed that dumb key.
These boats are for people who want to believe, but never took physics. It's too much of a side track for this thread, so if you want to discuss, just start a new thread.
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Old 05-28-2016, 08:56 AM   #43
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Originally Posted by twistedtree View Post
These boats are for people who want to believe, but never took physics. It's too much of a side track for this thread, so if you want to discuss, just start a new thread.
There have been threads on TF and other forums discussing electric motors on boats and all the assorted support systems they need. Suffice it to say; powering marine electric propulsion engines for pleasure crafts never meets the economy and speed people wish for. This is due to loss factors regarding energy creation, energy storage, energy transferal, energy use, hull drag, cumulative motor weights... as well as... a myriad of other items.

I feel bad for the souls who continue to try and make the elusive "Electric Powered" cruiser boat become a reality. Many I've seen go broke in so trying.

Electric cars - OK... at the drop of a hat it can be plugged in some place. But, there are still loss factors regarding energy creation, storage, transference, use... etc, etc.

What most electric car owners do not realize: Although the electric "grid" is increasing reception of electricity input via solar, geo thermal, wave, tidal, wind and other "green energy" actions/reactions... dirty burning coal is still by far the primary electric energy generator throughout the world. And, although advancements have been made for cleaner burning coal; due to loss factors (some are mentioned above) there currently is more pollution created by electrically re-charging a car each and every night than by utilizing a really clean burning, efficient hydrocarbon powered engine.

That said... If enough "green energy" electricity creation devices can become amply placed into use, then the tide of pollution factors will rest in favor of electric cars.

Side Note: Being there are over 1.5 billion hydrocarbon powered vehicle engines in existence with each made of metal that can be melted for return to use in manufacturing... what would be done with the really dangerous compounds inside modern-design batteries if eventually 1.5 billion electrically powered vehicles became a reality? Just thinking out loud!

Happy Energy Daze! - Art
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Old 05-28-2016, 12:02 PM   #44
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Originally Posted by twistedtree View Post
These boats are for people who want to believe, but never took physics. It's too much of a side track for this thread, so if you want to discuss, just start a new thread.
Electric is great if you want to go 20 nm. Of course if you want to go 20 nm or less then what does it really matter what your fuel usage is? Show me an actual 1000 nm trip taken on 100 gallons and then I'll believe those numbers of 10 nmpg. Until then the best I'll buy on Greenline is 6 or 7 nmpg, perhaps 8 and others have achieved that.

Then try going south in the gulf stream on electric. Or anywhere against a strong current when your 4 knots becomes 2 knots or 0 knots.

Greenline apparently does have some owners in Europe. If they're happy, that's fine. However, I have a feeling their happiness comes more from doing something unique than any savings. We're seeing progress on electric cars and perhaps one day we'll see it on electric boats. Until then the market of all electric will be owned by Duffy. Great if you just want to cruise the Fort Lauderdale canals for two or three hours in silence.

When we see technology advance to give autos a range of 1000 miles on one charge, then we'll have the technology for a true electric cruiser.
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