Longest time/distance you've had to motor?

[44'cruisingcat]

Originally Posted by bryguy67

It's too bad that diesel is the only way to charge the batteries. Seems like someone could invent a way to hydro-generate power while sailing, or use the wind or sun. Personally, my rotary dial phone works just fine. I think this whole touch tone thing is a passing fad.

Wind or solar simply don't (unless you can find the space for a truly huge solar array) provide enough power for sustained motoring. You can work that out with simple arithmetic.

Hydro generation can, but it will have quite an impact on sailing performance.

Or perhaps you think you could have one electric motor propelling, and the other generating, and that way you can run forever?

[barnakiel]

I am not sure why so many people want to generate say electricity from the sun, to charge the batteries, to run electric motors, to get somewhere.

The sun warms the air masses which creates the wind which takes me to where I want to get.

Why all this battery/engine stage while there are well known solutions that have worked for ages.

b.

[goat]

Just a matter of time before someone realizes a sail can be a solar panel and vise-versa, and batteries can be your ballast. Wish I was smart enough to think of that. Ah well....
Goat

[bryguy67]

If those who are against this type of system (for what ever reason) would take the time to research the ACTUAL results that people are getting while using similar systems then I think it would provide some better facts and understanding. Here's one link but there are many: http://www.moonwave.com/hybrid-system/
Yes, there is added drag by hydro-generating. Those who have the systems report about a half knot difference during normal cruising speeds. In lighter winds push a button and the clutch releases to freewheel and/or add very minimal e-power to the prop and negate all drag. Motor sailing can be done in silence and at low power can sustain for many hours. As for prefering your trusty Yanmars...this system has 2 of 'em. Plus two electric motors (nice to have when those filters clog in heavy seas). Plus sails (the prefered method of moving the vessel as someone just mentioned). No we will not need to have one diesel running to dock her. The two electric motors will do a fine job alone. And as for- "wind and solar simply don't provide enough power for sustained motoring"...of course they don't. This is a SAIL boat first. And twin diesels are there for when motoring is desired for more than 6 hours. This won't be the first hybrid catamaran out there. The early Lagoon hybrids that failed were "series hybrids" where a single generator provided power to large electric motors; No diesel provided direct power to the props. The systems that are providing more success are "parellel hybrids" which give the option of using either conventional diesel power to the props or electric. It's understandable that there's a lot of confusion between the two systems but a quick internet search will provide some good basic explanations. Conventional systems serve people well and will continue to. But these hybrid systems have many advantages to those who are open minded and properly research them.

[deckofficer]

bryguy67 has the best of both worlds with flexibility and redundancy. Until you have maneuvered in tight quarters with electric propulsion you just don't know what you are missing. No more clunking in and out of gear, no longer restricted to >700 rpm, and all the torque available at 1 rpm. As to economy of use, a diesel wants two things for best BMEP, and that is rpm and load. RPM would be at peak torque, load generally 80%. Meet this criteria and you extract the most work per unit of fuel burn. Problem is in most conditions (benign sea state and wind) rpm at max torque can be used but loading will be light so some efficiency in converting fuel to work is lower. Under these conditions bryguy67 has the option of more loading by charging his battery bank. Under severe conditions of high head winds and waves he will get the loading of the diesel just for propulsion duties.

This is the way to go. You don't need the weight penalty of an AC gen set that has to run at a frequency dependent rpm (1800 for 60 cycle AC). DC gen sets can be run at any rpm and are much lighter per power output than their AC equivalent. His system could also replace propane on board because you could enjoy a fully electric galley, running it quietly from the inverter and batteries.

[bryguy67]

That Moonwave link was a serial hybrid system. Here's a simple parallel sytem that can work with either sail drives or shaft drives:
http://www.hybrid-marine.co.uk/resou...d+brochure.pdf

[44'cruisingcat]

Originally Posted by goat

Just a matter of time before someone realizes a sail can be a solar panel and vise-versa, and batteries can be your ballast. Wish I was smart enough to think of that. Ah well....
Goat

Ballast? Who wants that?

[mikereed100]

We cheated and used the sails for a couple hours here and there, but essentially motored all the way from Kodiak to Point Arguello (S. Calif.)

[Jim Cate]

Originally Posted by mikereed100

We cheated and used the sails for a couple hours here and there, but essentially motored all the way from Kodiak to Point Arguello (S. Calif.)

Just curious: on this route which is usually blessed along much of the way by reliable NW winds, how did this come to pass?

Jim

[bfloyd4445]

Originally Posted by Aargau

I feel like solar/battery/brushless electric propulsion will be the wave of the future once battery energy density gets within 15% of diesel, but right now it's not.

However, the longest I've had to motor was 2 days, and that wasn't strictly necessary, light winds between Tonga and Fiji. It was a pretty slow but sturdy monohull, and we had a flight schedule. Same boat had to motor 4 days between Galapagos and Marquesas, but that was also due to some urgency with supplies and repairs.

So I'm interested in real life examples of necessary long motors, such that if an electric/battery motor can't meet that range, it's not ready. I would be doing another trans-pac and possible round the world trip, so anywhere that requires sustained motoring is interesting.

seems to me with solar and wind generators electric is very possible today. In much of the world there is sun, wind most days so you would choose batteries that will give you the reserve power you need for the expected no wind no sun time in your area of interest. Oh, and there are also water generators but they do cause a bit of drag. I'm seeing more and more cruising boats with both wind and solar gens so its only a matter of time till the engine is also.
Keep in mind you don't need a large engine as electric motors develop max torq from the start. If you have a D engine now why not consider a hybrid? Proprtly installed it can run on electric, diesel, or a combination of both. Cant loose there. Downeast yachts used an electric motor to give get home capabilities to their DeFever trawlers back in the 70's with success. They used a belt and pulleys to engage the electric to the prop shaft with the main engines transmission in neutral

forgot to mention I plan on doing this to my sailboat here shortly after I find a suitable boat to buy

[JRM]

Originally Posted by deckofficer

bryguy67 has the best of both worlds with flexibility and redundancy. Until you have maneuvered in tight quarters with electric propulsion you just don't know what you are missing. No more clunking in and out of gear, no longer restricted to >700 rpm, and all the torque available at 1 rpm.

This!

Going back and forth between the electric boat and the diesel one taunts me so. If only the big boat could be the electric... I just can't justify the cost if replacing my perfectly good diesel in the bigger boat... Someday, maybe...

JRM

[bfloyd4445]

Originally Posted by JRM

This!

Going back and forth between the electric boat and the diesel one taunts me so. If only the big boat could be the electric... I just can't justify the cost if replacing my perfectly good diesel in the bigger boat... Someday, maybe...

JRM

you don't have do go hybrid. Even west marine sells systems for that now. Then if the D breaks down you still have electric

[bfloyd4445]

Originally Posted by Jim Cate

Just curious: on this route which is usually blessed along much of the way by reliable NW winds, how did this come to pass?

Jim

good question....I get it, what a dummy, the starter didn't have enough energy to hoist the sails....te..he..

[bfloyd4445]

Originally Posted by lonesoldier0408

There is always a loss of energy associated with the conversion of the energy from type to type and work performed...

but who cares if the energy is free?

[frugalvoyager]

Sorry, but I don't understand your point. I have motored my monohull (not because I had to, but because I wanted to) the entire 5,600 statute miles (and 112 actually cruising days) around America's Great Loop.
Many sailors motor a 1,000 miles (or more) up/down the entire lengths of the Atlantic ICW and Gulf ICW annually. In addition, it is also true, many motor down the inland rivers from Chicago to the Gulf of Mexico every year.
So, my question is what is the point of your question? Solomon Technologies has had (for years) the capability of producing an all electric/solar 40' plus catamran to sail around the world - and in fact, more than one (I know of) have crossed the Atlantic.