# Electric Sail Boat Motor



## TSOJOURNER

Does anyone have any info on electric Sail boat motors. Re: which is the best etc. I am looking to put together a system using the Mars brushless motor. Is there a better motor out there. Our boat is a 27ft Catalina. Any info would be appreciated.


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## negrini

They have some unities installed on catamarans too. Never had one, but reading reviews and comments for some years, they looks like a very competent and serous company:

Solomon Technologies


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## davidpm

These guys have a good site:
Hybrid Propulsion

The bottom line is that by the time you are done it will probably cost the 10g plus, that a new diesel will cost.


You will get maybe two hours between charges.
You will have to be at a dock with shore power.
It is louder than you might think because of the gearing.
Long term costs will be higher than diesel as the batteries, a large part of the system cost, will have to be replaced every few years.
I'm not sure of this but I suspect that maintenance or at least attention will be high as the systems are new.
Resale value will likely be low.
The Catalina 27 is a good boat for this experiment, big enough to hold some batteries but an easy to drive hull.
I love the idea and plan on visiting "above the waterline" this winter.
A fully do-it-yourself setup may be cheaper but you will be inventing the engineering as you go.
I am very interested in this so if you want to go further call me or email, my contact info is in my profile page.


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## JCR

*Electric Sailboat Motors*

Just some feedback about electric sailboat motors.....

I have some 1st hand knowledge of electric propulsion and maybe can answer questions you may have.

1. Electric boat conversions are not difficult to do.

2. They provide you with many advantages over gas & diesel motors.

3. Electric boat motors are regenerative if they are designed properly; meaning that they will recharge the batteries when you are sailing.

4. Electric boat drives are clean, almost maintenance free and easy to use.

5. Electric boat drives installed in sailboats typically can be charged overnight and maybe much shorter times and the cost can be very low like $1.50 per charge.

JCR


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## JCR

*LaNinfa,*

Try electricyacht.com as they have experience providing electric propulsion units with your kind of boat.

If you have other questions you can contact me.

JCR


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## TSOJOURNER

*electric Sail Boat Charging*

I am looking to put a small generator on board mounted in rear stern area to give additional otions for recharge. Also a wind genreator. Do you have any information on how all of this hooks together. If I want to use the generator for internal power, lights etc. and also charge the batteries, or just use the wind generator for charging as I sail etc. Do I need a different battery bank for lights other than the batteries for the electric motor. It is 3-phase so If I use the 3-phase 48 volt sytem for internal items I will have to get an inverter? Please any info would help. Also I have tried to contact the individuals at electric yacht that designed the catalina 27 system. They had a motor mount system that worked. They had stuck a Sea-Ev sticker on it. Where would I find the mount or do I need to fab' one. 
Thanks for your time to reply previously. Hope to hear from you soon.



JCR said:


> Just some feedback about electric sailboat motors.....
> 
> I have some 1st hand knowledge of electric propulsion and maybe can answer questions you may have.
> 
> 1. Electric boat conversions are not difficult to do.
> 
> 2. They provide you with many advantages over gas & diesel motors.
> 
> 3. Electric boat motors are regenerative if they are designed properly; meaning that they will recharge the batteries when you are sailing.
> 
> 4. Electric boat drives are clean, almost maintenance free and easy to use.
> 
> 5. Electric boat drives installed in sailboats typically can be charged overnight and maybe much shorter times and the cost can be very low like $1.50 per charge.
> 
> JCR


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## JCR

*Electric Boat Conversions*

LaNinfa,

There are various ways to accomplish what you want to do. You have to choose the approach to provide a safe, reliable, electrical, charging and propulsion system that makes sense for your boat and each boat will be different.

For example assume for a moment you want to power your boat with an electric motor propulsion system and two 48 Volt battery packs. You will need low voltage power (house load) for lights, bilge pump, radio, navigation electronics, horn, etc. You can choose to have separate battery power for the 12 Volt system or run a converter from 48V to 12V for your low house load power. Your choice will depend upon how confident you are in either approach.

Some people would recommend that a separate battery for the 12 Volt house load is a good idea because if there is ever a problem with the 48 Volt electric propulsion system you still have 12 Volt power for the radio, bilge pump, horn, lights etc.

Other people would say that a well designed and properly wired 48 Volt electric propulsion motor with large battery packs and a converter is as safe as it gets and your battery packs will supply both 48 Volt power to the propulsion motors and the converter will supply the 12 Volts for the house load.

There are some issues you need to consider that are important when you convert your boat to run on electric propulsion. The 48 Volt Battery pack wires that go from the battery packs to motor and motor controller should be kept as short as possible, be of the correct wire grade and size and keep the heavy voltage wires separate from the light voltage wires. Also, make sure you have a properly wired & grounded sytem.

I suggest using 2 battery packs connecting the battery cables thru main fuses to a battery switch (1/2/all) and then run the battery cables to the motor controller keeping these heavy voltage cables together on the left or right side of the boat. This will reduce and hopefully eliminate the electrical noise in your low voltage house current. Electrical noise can effect radio reception, navigation instruments, etc. You might want to run the low voltage house load wires on the steering console side of the boat and run the Battery cable wires on the opposite side to keep them apart. Typically, if the motor controller is mounted vertical or horizontal bow to stern so the low voltage motor signal control wires can attach to one side of the controller while the battery cables can be mounted to the opposite side of the controller. This is one way to keep the 48 voltage wires apart from the 12 volt house load wires.

You can choose many different ways to recharge the main battery packs and/or house batteries with the wind, sun, generators, etc. Are you running the generator to recharge the battery packs or are you running the generator to power the electric motors while running the boat? The different answers to these questions may require different switching electronics and controls.

I believe that a separate 12 Volt house load battery or batteries with a small wind turbine and/or solar cells for recharging is a good idea. If you want redundancy for the house load power include a converter to get 12 Volts from the 48 Volt battery packs. As far as charging the 48 volt battery packs I believe that solar cells or wind turbines would take a long time and the technology may not quite be there.

Inherently, electric boat propulsion is simple and straight forward.

I hope this has been helpful.

JCR


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## Mark F

Hi LaNinfa,

I've got an Ericson 27 with a SolidNav Explorer. I think the Electric Sailboat frame/mount/reduction/shaft/motor is an early Explorer unit. Electric Sailboat isn't a company any more as far as I know. 

There has been some good information here. I agree with the two separate 48volt bank comments, it gives you some redundancy. On my boat there are two separate house batteries but as said you can get an inverter to do the same thing. I charge off of shorepower. 

I've had the electric inboard installed on my boat since may of '08 and have had no real problems. A friend wanted to see the motor the other day and I realized I hadn't had the "engine" cover off in quite a while, not much to do to it once it's installed! 

The longest I've motored is a little over 7 hours at 4 knots and did not use all available power from just one of the banks. For my use I couldn't be happier, good luck with your install.


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## huguley3

I was looking into an electric for my boat awhile ago. I don't have a lot of faith in my current diesel but I tabled the plans as I don't have a place to put the batteries or a generator to keep a smaller bank charged up to what I wanted to be able to motor. This is what I was looking at: 5 KW Inboard Oddysey makes some rack mounted batteries in a form that would have been workable for me but the cost was too much. So I am sticking with the diesel until it dies.

There is a guy here in the marina with a pretty big Gulfstar and he put a forklift motor in it and it is working ok. He needs to get a new prop as he found out the motor does have a prefered direction it wants to rotate and he has to put the engine in reverse to go forward. he said it does back up quite well though. 

You may have issues charging a 48v bank with wind or solar though. 12v seems to be the predominant output of the units so you would need a clever charge controller that may not exist to step up the voltage to charge level or run panels in a group of 4 to get the voltage up. I did not get very far into it before deciding it would not work as well as I had hoped.


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## Mark F

For me battery installation was the hardest part of repowering with electric. I ended up with 4 group 27's under the starboard settee and 4 group 31's under the port side settee on my Ericson 27. This placement gives me battery weight low and centered. Being the first time, there was a lot of head scratching trying to figure out where to put the batteries and charger. The next one would go pretty quickly .


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## sailingdog

While electric power may make sense for a daysailer, it isn't a good idea for a cruising boat. If the boat requires moving under power in hazardous conditions for prolonged periods of time, the real problem is that the electrical bank can not be easily replenished. If the generator is large enough to power the motor without the aid of the battery bank, then there is little in the way of weight or energy savings.


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## utx1977

[I am very interested in electric conversion. Cd you send me your email address:

Vendors for electric motors, batteries and controllers.
Install checklist
Cost range. I need no more than 10hp equivalent.

My boat is a 1980 Hunter 27.

Thanks.

David Miller
[/email]UOTE=JCR;539576]Just some feedback about electric sailboat motors.....

I have some 1st hand knowledge of electric propulsion and maybe can answer questions you may have.

1. Electric boat conversions are not difficult to do.

2. They provide you with many advantages over gas & diesel motors.

3. Electric boat motors are regenerative if they are designed properly; meaning that they will recharge the batteries when you are sailing.

4. Electric boat drives are clean, almost maintenance free and easy to use.

5. Electric boat drives installed in sailboats typically can be charged overnight and maybe much shorter times and the cost can be very low like $1.50 per charge.

JCR[/QUOTE]


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## tommays

Well

If you follow the JCR links you will find like 4 to 8 boats that max out at about 20 miles


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## Mark F

What are JCR links? 

I do know that my Ericson 27 with a 200 amp hour reserve (two sets of four 12 volt agm's) will go at least 60 miles at 4 knots boat speed. Probably a fair amount farther. There is a SolidNav Explorer on a Bristol 32 in New York getting 100 miles.


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## JCR

utx1977 said:


> [I am very interested in electric conversion. Cd you send me your email address:
> 
> Vendors for electric motors, batteries and controllers.
> Install checklist
> Cost range. I need no more than 10hp equivalent.
> 
> My boat is a 1980 Hunter 27.
> 
> Thanks.
> 
> David Miller
> [/email]UOTE=JCR;539576]Just some feedback about electric sailboat motors.....
> 
> I have some 1st hand knowledge of electric propulsion and maybe can answer questions you may have.
> 
> 1. Electric boat conversions are not difficult to do.
> 
> 2. They provide you with many advantages over gas & diesel motors.
> 
> 3. Electric boat motors are regenerative if they are designed properly; meaning that they will recharge the batteries when you are sailing.
> 
> 4. Electric boat drives are clean, almost maintenance free and easy to use.
> 
> 5. Electric boat drives installed in sailboats typically can be charged overnight and maybe much shorter times and the cost can be very low like $1.50 per charge.
> 
> JCR


[/QUOTE]

David,

I have a new brushless 5kw motor, controller, reducer and motor mounting hardware if you are interested. Perfect fit for your sailboat.

JCR


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## JCR

LaNinfa said:


> Does anyone have any info on electric Sail boat motors. Re: which is the best etc. I am looking to put together a system using the Mars brushless motor. Is there a better motor out there. Our boat is a 27ft Catalina. Any info would be appreciated.


How is your electric sailboat project going
JCR


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## COOL

David,

I have a new brushless 5kw motor, controller, reducer and motor mounting hardware if you are interested. Perfect fit for your sailboat.

JCR[/QUOTE]

How do you compare kw to HP?
What would this system weigh in at?
I am planning to replace a 20HP diesel engine with
an electric propulsion system. I would like the total
weight of the electric, including the battery bank to
be substantially lighter than the diesel. I plan to
drive the existing Saildrive with a belt.
The motor will only be used for maneuvering out of
the slip, sailing commences immediately after.


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## klem

COOL,

740W/HP. For example, a 20hp engine could be replaced with a 15kw motor (make sure that is the continuous rating). You need to make sure you gear it correctly though which shouldn't be too hard with a belt. The trick with a belt is that you need to add a bearing to the shaft.

The weight in the system primarily is in the batteries. I would guess that you can get a motor and mounts to be 75lbs and another 75lbs for the charger, controller, contactors, and wiring. Having it be lighter than the diesel is probably not realistic if you want it to propel you anywhere.

Figure out how much power you expect to use for how long and you can get the KWH requirement for the batteries. Then you can look at batteries and figure out what you need/what weight. You will have to get a battery pack that allows you to configure it so that the voltage is compatible with the motor (usually 48,72,120,or 156V, higher is better for efficiency and smaller battery cables). There was another thread here that touched on this subject and I did a very basic calculation for a 15kw motor run at WOT for 2 hours and found you would need 18 Trojan T-105 batteries(I hope I am remembering that right). Now if you throttled back to 5kw, you would only need 1/3 the battery capacity. Lead acid batteries are not great for energy/weight but they are often used since they are the cheapest. If you went with 8 of these batteries in series, you could use 48V components and you would be able to get in and out of the slip just fine but you would have a few hundred pounds tied up in batteries. This combo would probably get you home 10 miles in flat calm conditions on a 30 footer as well.


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## JCR

Cool

The conversion is 1 KW = 1.34 HP so the 5 KW Motor = 6.7 HP 
The 5KW motor/mounting bracket/controller/reducer weigh 58.5 lbs
The motor/controller requires 48 volt batteries.
The battery modules I use are 12.8 volts x 100 AH each and weigh 29 lbs. 
Tell me more about your boat, engine, propeller shaft speed and the existing saildrive.

JCR


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## scottyt

jcr just wondering are you connected with a company or are you just a knowledgeable person


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## JCR

Scotty,

I have authorization from Electric Yacht to install Electric Sailboat kits and have designed, installed and sea tested propulsion drives as well. There are many companies offering electric boat conversion motors, controllers, reducers and complete kits including Solidnav, Asmo Marine, Electric Yacht, Solomon, EV sports, Vetus, Oz Marine, Elco, etc. Some kits start at $1,500 but buyer beware they do not include motor mounting hardware. Batteries to power your new electric propulsion system are never included. You might keep in mind that every boat is different and one does not fit all. If you have a sailboat or powerboat you want to convert to electric propulsion I would like to help. 

My interest in propulsion design & engineering and elecric motor systems in boats goes back 10 years but advances in battery power density did not catch up until about 2006. There are many ways to push boats with electric motor propulsion. If someone tells you to use this kind of motor there are 10 other people that will tell you about 10 other motors. Some will recommend DC and others swear by AC and everything in between. The most important thing to consider if you are going to convert your boat from gas or diesel to electric propulsion is safety. The Underwriters Laboratories (UL) is in the process of developing national saftey standards for battery pack use in electric vehicles as is the SAE. 

JCR


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## ChicagoNewport27

Here is an example of a guy that repowered his Newport 28 with a Re-E-Power electric engine:
E-POD 3000+ - Petaris' Photos

We've been discussing it over on the Capital Yachts/Newport mailing list, here:
Yahoo! Groups

To quote the owner, Justin Paulsen:


> Well the first thing that I'll mention is that it has torque. Forward and reverse are both very responsive and since we back in to the slip it has made a big difference. We are still really getting used to the system, even though this was season 2 with it, as since we installed it we haven't had a lot of time to use it. Though it has had some good tests. The hull speed has slowed and there is a bit more drag when sailing. The batteries have never run out and I have given them a good 8 hours of use before charging them again. We are kind of guessing we could get 10 hours or maybe more out of them but haven't tested that yet, though I hope to next season. The recharge time is long and I usually let it go overnight but I would say its a good 5 hours maybe a bit more, though some of that is float time. I took the photos of the corrosion so that Kevin at Re-E-Power could see them and advise on it. He said that it wouldn't be an issue. That was after one season in the water and my seasons are generally the middle to the end of May until the first weekend in November. It didn't affect the operation of the motor though. By the way Kevin has been very helpful with any issues that have come up with the system though he can be difficult to get a hold of.
> <O</O
> There have been issues though. For one the controller kept overheating the first season even after adding cooling fins and fans, though they did help a lot, and we had to have the prop pitch changed on Kevin's advice, we sent it to him and he had it done and sent back to us (he paid for all but sending it to him). Also the controller is something we came up with as the one that came with it was just tiny, ours is to but since we changed it we were able to mount it on the tiller which is both a great place for it, convenience wise, and a not so great place as its easy to bump with your leg.


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## mitiempo

Why would the hull speed slow and why would there be more drag while sailing?


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## huguley3

mitiempo said:


> Why would the hull speed slow and why would there be more drag while sailing?


They probably meant top speed. My diesel was smallish anyway so a replacement electric probably would have given me the same top speed had I went that route. The electrics can recharge the batteries while sailing by letting the spinning prop run the engine like an alternator. That adds some drag to keep the prop spinning. Even more so since most places recommend a larger prop on the electric.


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## KeelHaulin

mitiempo said:


> Why would the hull speed slow and why would there be more drag while sailing?


The motor is in a pod mounted beneath the hull; and the prop looks more like a powerboat prop than one designed for a sailboat.


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## mitiempo

Oh, I see.


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## COOL

JCR said:


> Cool
> 
> Tell me more about your boat, engine, propeller shaft speed and the existing saildrive.
> 
> JCR


JCR,
The boat is a custom built Lancer 36, originally
built as a race boat with minimal furniture.
The boat displaces 10,500 lbs on 29' LWL, so
it is very easily driven.
The engine is a Volvo MD 11C with a 110S Saildrive.
When I am able to get the machine started, which has always
been an issue, it will push the boat at 7.5 knots at 2500 rpm.
The shaft output is rated at 17 kW at that speed. 
The ratio is 1.66:1.
The current prop is a 2 blade fixed , maybe a 16"x11", it seems
to be too much prop and the acceleration will throw off your
feet when you ease it in to gear. I will eventually go with a
folding prop of some sort.
I am guessing that I will not need a thrust bearing for the belt
drive, but I will build a composite structure to support the
Saildrive, since it was supported by the engine.
i do not know how yet to configure the ground loop 
for the electrical system, that was connected to the 
engine block.
My expectation is to get into and out of the slip,
we are sailors and not motorsailors.


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## silverbranch

ChicagoNewport27 said:


> Here is an example of a guy that repowered his Newport 28 with a Re-E-Power electric engine:
> E-POD 3000+ - Petaris' Photos


I looked at these pictures a while back and the ones on the last page look like the motor is in bad shape. So he is still happy with it and it's working?


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## mitiempo

I want to start by saying that I know almost nothing about electric boat propulsion. But after looking at all 165 pics in the link that was posted I have some questions. Why is the motor mounted like it is below the hull? It doesn't look too good in the last few pics I agree. Why not mount the motor inside the hull and use a normal shaft, stern bearing, and cutlass? Wouldn't this protect the motor a bit better? The angle of the prop looks wrong as well - the forward end of the nacelle is higher than tha aft end, resulting in a prop that is nowhere near the angle a normal fuel powered boat has for its shaft.


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## tommays

This would seem to be a pretty BADLY failed project as you still dealing with saildrives and other motors big issue water infiltration through seals and corrosion


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## Ajax_MD

sailingdog said:


> While electric power may make sense for a daysailer, it isn't a good idea for a cruising boat. If the boat requires moving under power in hazardous conditions for prolonged periods of time, the real problem is that the electrical bank can not be easily replenished. If the generator is large enough to power the motor without the aid of the battery bank, then there is little in the way of weight or energy savings.


Sailingdog is right. I have some knowledge of electric propulsion systems as I recently built and drive a 1974 VW Beetle that has been converted to battery-electric drive. I put 10,000 miles on it, and it has a top speed of 70 mph so it was highway capable. The best range I ever got out of it was 40 miles. I also investigated an electric outboard on a pontoon boat with solar panels on the roof.

Daysailer: yes
Long-range cruiser? not a good idea.

The problem is simply the batteries. Current battery technology is just not a large enough storage medium (too small of a "fuel" tank). If you get caught in a hard blow, or a situation where you need _sustained_ auxiliary propulsion, you'll be screwed. You would have to positively upholster your boat in solar panels and wind turbines to get an appreciable charge into them without shorepower.

The batteries are expensive. I used 8 volt golf cart batteries. 16 of these ran me about $1500. Golf cart batteries are the ONLY batteries that can stand up to this application. "Deep Cycle" Marine batteries absolutely will not stand up to this kind of abuse, neither will 12v gelcell batteries.

If you have unlimited money to throw at this project, new Lithium batteries are smaller, lighter, and hold more energy. There are several chemistry varients: Lithium cobalt, Lithium sodium, etc. Unfortunately, Lithium batteries absolutely require a computer controlled management system to keep them balanced without destroying them. Lead acid batteries do not because you can safely (for a time) overcharge the "full" batteries while the laggers catch up and achieve full charge. The result is that the full batteries have boiled away some electrolyte and you just add de-mineralized water. You can't add water to a Lithium chemistry battery.

It's a good idea, and I'm not saying you shouldn't do it, but I am saying that you shouldn't do it on a blue water boat or long-range coastal cruiser. A day-sailer that stays near home is most appropriate under today's battery and charger limitations.

I can provide more information, but I think I've gone on long enough.


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## JCR

COOL said:


> JCR,
> The boat is a custom built Lancer 36, originally
> built as a race boat with minimal furniture.
> The boat displaces 10,500 lbs on 29' LWL, so
> it is very easily driven.
> The engine is a Volvo MD 11C with a 110S Saildrive.
> When I am able to get the machine started, which has always
> been an issue, it will push the boat at 7.5 knots at 2500 rpm.
> The shaft output is rated at 17 kW at that speed.
> The ratio is 1.66:1.
> The current prop is a 2 blade fixed , maybe a 16"x11", it seems
> to be too much prop and the acceleration will throw off your
> feet when you ease it in to gear. I will eventually go with a
> folding prop of some sort.
> I am guessing that I will not need a thrust bearing for the belt
> drive, but I will build a composite structure to support the
> Saildrive, since it was supported by the engine.
> i do not know how yet to configure the ground loop
> for the electrical system, that was connected to the
> engine block.
> My expectation is to get into and out of the slip,
> we are sailors and not motorsailors.


Cool

I am a little surprised that it takes 17KW to push your boat basically at your hull speed of around 7.2 knots. Any thoughts of changing over to straight inboard when you refit to electric propulsion? I agree you should not need a thrust bearing if you are belt powering your saildrive. Please know that an electric drive is most easily suited for an inboard setup and is very basic and simple once you complete the actual mounting installation. But certainly you can do what you are suggesting. If you need help or just some pointers to help you let me know.

JCR


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## mitiempo

Not to mention the drag.


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## Mark F

Cool,

You might be interested in this; http://www.sillette.co.uk/elect_saildrives.pdf

Good luck with your repower.


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## COOL

JCR said:


> Cool
> 
> Any thoughts of changing over to straight inboard when you refit to electric propulsion?
> 
> JCR


If you mean a propshaft and stuffing box arrangement, 
then No. 
The Saildrive is in good shape, and the boat came
with an unused spare just like it. I plan to do the project
in the water. And my ultimate pipedream would be to devise
a retractable drive leg that seals flush with the hull.
Thank you for the helpfull comments.My first, and most
difficult step will be to remove the big hunk of iron.


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## SURV69

If we could forget about "hull-speed" and spend more time considering a speed that requires far less energy, electric would look much more viable.

First off I don't rely on speed after playing "chicken" with a storm before I finally realize that it has me in it's sights. I preplan my sailing regarding forecasted weather. When I do get it wrong, hull-speed doesn't seem to move me fast enough anyway.

I'm ready for electric and the purported shortcomings(?) that are associated with it, even if it means moving at 2 knots in the duldrums, as long as I can get rid that #$&*#% motor.


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## bljones

One absolutely insurmountable advantage that an internal combustion engine has over an electric drive system- instant refueling. We can compare power output and weight and whether we really really need to travel at hull speed until the end of time, but you cannot get around the fact that when you run out of diesel or gas, you can fill up your tank and restart. Sure, you could keep a spare bank of batteries on standby, but that is just one more bank to wire, store, charge, and pay for. It is a hell of a lot easier to store five or ten gallon cans of diesel or gas on board than it is to try to store a spare bank of fully charged batteries.

Respectfully, those of you who are tearing out your engines to install electric drives because you are unable to get your IC engines to run reliably will likely also have big problems with electric drives as well. if you cannot handle the basic maintenance and repair needs of an IC engine, you will be utterly clueless at troubleshooting and maintaining a cobbled together multiple battery electric drive.

And why anyone would spend upwards of $3k to install an electric drive to avoid the $2k cost of making an Atomic 4, Westerbeke or Yanmar trouble-free is beyond me.


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## COOL

bljones said:


> One absolutely insurmountable advantage that an internal combustion engine has over an electric drive system- instant refueling.
> And why anyone would spend upwards of $3k to install an electric drive to avoid the $2k cost of making an Atomic 4, Westerbeke or Yanmar trouble-free is beyond me.


If you run out of diesel or gasoline in the the middle of the ocean,
you will have no opportunity to refuel until you reach civilization.
With an electric system, you have the ability to regenerate or
recharge through solar panels. It may take some time, but you
still have an option.
If you spend $2000 on an old A4, you will still have an A4.


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## tommays

My A4 is 40 years young and just had its first full service and was pulled because the shaft log required a repiar and other PO compleat lack of matiance

We move a C&C 35 MARK I at 7+ knots with a 13.5 HP diesel i would think the prop is your leading issue

It only has a 10 gallon tank as at 14 MPG we never have a range issue


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## mitiempo

In reply to COOL
If you're offshore I doubt you could charge the battery banks enough for much motive power as you'd have enough trouble gathering enough amps from the sun or wind for daily use. Unless you started a generator and if you're going to have one of those why not just have an engine.


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## nickmerc

The main issue with electric motors is power storage. It is really hard to beat the power density of fossil fuels. On the other hand there is alot to be said in favor of electric motors. Instead of going into that here, please search the net for plenty of opinions and facts.

In my opinion, and if I had the budget/need to repower, I would install an electric motor. Since power storage is still an issue I would put a battery bank sized for 4 hours at 80% power at about 80% hull speed coupled with a diesel (or gas if need be) generator sized for an alternator that can run the electric motor at 80% power. I would also add solar and wind power to charge the bank over time. Regen while sailing will also recharge the bank.

I understand the inefficiency of this system. However, the electric motor itself is not the weak link. The benefit of this setup is when electrical power storage technology improves you can change out your power storage system.

This entire plan assumes that power storage will improve drastically in the near future. I think the push for electric cars will really benefit other industries.

Bring on the comments.
________
Buy bubblers


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## sailingdog

One other point to consider is the on-going cost of replacing the batteries... batteries have a finite lifespan, and in an electric propulsion setup with little recharging capacity, likely to have far shorter than normal lifespans. Replacing a large battery bank is not all that inexpensive and has significant costs to the environment as well.


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## mitiempo

sailingdog is right. The cost of replacing batteries every 4 or 5 years if they last that long far outweighs the maintenance cost on a diesel.


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## COOL

sailingdog said:


> Replacing a large battery bank is not all that inexpensive and has significant costs to the environment as well.


I plan to use 4 traditional lead acid batteries in my
system, which will cost about $800.
The batteries will remain at or near full charge
a majority of the time utilizing AC shore power.
The company which manufactures the batteries
I intend to use, claims to recycle 100% of the 
truck loads of batteries that they receive each week.
There is no such thing a completely 'green' propulsion,
and there is likely some pollution and environmental 
destruction associated with batteries.
What happens if you track your diesel or gasoline from
the time it is extracted from the ground until it is
exhausted from your tail pipe?
There are many steps in the process that are detrimental
to the environment.


----------



## bljones

I call shenanigans on 100% battery recycling. Yeah, 100 % of all the batteries that come in may get dismantled, but not 100% of the contents gets reused.
"Likely some pollution and environmental destruction"?
Yeah, acid and lead are a little harmful, both in the extraction and creation process, and on the back end recycling process. Why do you think most battery recycling takes place in countries with little environmental oversight?


----------



## COOL

bljones said:


> 100 % of all the batteries that come in may get dismantled, but not 100% of the contents gets reused.
> 
> Yeah, acid and lead are a little harmful, both in the extraction and creation process, and on the back end recycling process. Why do you think most battery recycling takes place in countries with little environmental oversight?


I have no way to verify their claims, but look
into the East Penn battery plant in Pennsylvania.
They say they recycle 100% of the battery in a 
environmentally friendly process. I find it hard to
imagine that lead smelting can be very clean,
but this operation looks to be quite different
than kids in India smashing Ni Cads with a 
hammer.


----------



## tomwatt

COOL said:


> I plan to use 4 traditional lead acid batteries in my
> system, which will cost about $800.
> The batteries will remain at or near full charge
> a majority of the time utilizing AC shore power.
> The company which manufactures the batteries
> I intend to use, claims to recycle 100% of the
> truck loads of batteries that they receive each week.
> There is no such thing a completely 'green' propulsion,
> and there is likely some pollution and environmental
> destruction associated with batteries.
> What happens if you track your diesel or gasoline from
> the time it is extracted from the ground until it is
> exhausted from your tail pipe?
> There are many steps in the process that are detrimental
> to the environment.


I'm curious as to your battery sizing/pricing formula here. When I tried to run the numbers for an electric setup, I ended up with a 48v system using T105s and over $1100 to get a 225ah system (weight? ouch = 550+ lbs.). Using the slightly larger 8Ds gave me over $2200 and 630+ lbs. But such a system doesn't provide very many hours of motoring time... and using a fairly decently sized solar system to recharge yields a very leisurely pace = motor one day, recharge 3 days.
Since I'm still in a number crunching stage, I'm fortunate to say I haven't committed the cash yet, because it looks like a rough way to have to go. As the necessity of dodging a hurricane by motoring upriver could not be answered by such a system. Leaving the need for an auxilliary fossil-powered engine anyway.


----------



## mitiempo

Until batteries change drastically, allowing much faster charging and hopefully less weight, unless you daysail and then plug in electric propulsion doesn't make sense, either in use or cost. When new battery technology does arrive it won't be cheap, at least not for a long time. Yanmar doesn't have to worry for a long time.


----------



## Mark F

I've been hesitant to jump in here with the latest posts about diesel motors being greener than electric motors... 

Something not mentioned lately is the quality of life on a boat with an electric system. I enjoy the lack of gas/diesel smell while at anchor and motoring. The relative quietness of an electric motor when motoring is also more comfortable, to me. 

The fuel density of diesel is hard to beat but I'm OK with a single charge range of 70 miles at 4knots.


----------



## COOL

tomwatt said:


> I'm curious as to your battery sizing/pricing formula here. When I tried to run the numbers for an electric setup, I ended up with a 48v system using T105s and over $1100 to get a 225ah system (weight? ouch = 550+ lbs.).


My initial set up is going to consist of one bank
of 4 12V Group 31 batteries at about 60# and $200 each.
Based on the system I am emulating, which has been
in service for two years with no problems, this should meet
my requirements.
I have a light responsive sailboat, and sail in and out 
the slip, and onto and off the anchor, a majority of the
time. The auxiliary power is only really needed on occaisions
where the wind is on the nose in the fairway to and from
my slip. This one major advantage of the electric, there
is no start up, if you need a burst of power 
it is at the ready, put in gear and go.


----------



## tomwatt

COOL said:


> My initial set up is going to consist of one bank
> of 4 12V Group 31 batteries at about 60# and $200 each.
> Based on the system I am emulating, which has been
> in service for two years with no problems, this should meet
> my requirements.
> I have a light responsive sailboat, and sail in and out
> the slip, and onto and off the anchor, a majority of the
> time. The auxiliary power is only really needed on occaisions
> where the wind is on the nose in the fairway to and from
> my slip. This one major advantage of the electric, there
> is no start up, if you need a burst of power
> it is at the ready, put in gear and go.


I'm seeing Group 31s as having about 105ah (and about 70 lbs. apiece in weight)... unless you're running a 12v electric motor, I don't see how you'd have enough juice to do much of anything without draining your batteries.


----------



## dman

We have an electric motor turning a prop,electric heater,electric fridge,electronics,lights,windlass...sounds like we need to go nuclear.


----------



## tomwatt

dman said:


> We have an electric motor turning a prop,electric heater,electric fridge,electronics,lights,windlass...sounds like we need to go nuclear.


Once you go nuclear, can I have your motor?
That's a funny response...
and I'm not interested in being contrary or making an argument... I'm just trying to lay out my hoped-for system and trying to do the math to get it to come out reasonably.
So I'm just curious how it's working out. I haven't seen any motors with any appreciable push-power in less than 24v, and the Torqueedo is a 48v for the 10hp equivalent. That makes for a pile of batteries.


----------



## dman

A pile..you`re spot on there T.If you look at practical power,take a chainsaw with a few cups of gas in it,you can mow down alot of trees...take an electric chainsaw and run it from a battery.Its things like that which show the average person whats what.BTW you guys there is a better way to go green..its called sailing.


----------



## COOL

tomwatt said:


> I'm seeing Group 31s as having about 105ah (and about 70 lbs. apiece in weight)... unless you're running a 12v electric motor, I don't see how you'd have enough juice to do much of anything without draining your batteries.


105ah is correct. It will be a 48V motor.
I am not anticipating a spectacular range from the system.
Based on a similar configuration, I may see a 30A draw at about
4Kts boatspeed and perhaps 50A at 5Kts. I would only be able
to run at or near full power, 15HP, for a very brief period.
But I realistically only 'need' to power at 3Kts for 3-5 minutes,
after that the sails will be up.


----------



## mitiempo

That is the most minimal battery system for electric propulsion I have ever heard mentioned. 105 AH @48 volts. To drain the batteries to 50% SOC, beyond which their life is shortened a great deal, that's 52.5 AH and that is at the 20 hour rate. A 50 amp load for less than an hout would drain this size bank totally. It would only work for short runs at smaller loads.


----------



## bljones

I think you are confusing "realistically" with "optimistically".
You have not accounted for power loss as the voltage drops, Nor have you accounted for charge time.
Here's what I mean:
On Friday night you head out for a sail after work, and motor off the mooring (15 minutes). Your buddy calls you at 7 to tell you that he has met two swedish exchange students who love to sail, and he mentioned you have a boat. You motor back to the mooring(15 minutes). Pick up the chicks, motor off the mooring, (15 minutes) with the stereo blasting ABBA, and all lights blazing cuz these chicks are swedish and you don't want to miss anything in the failing light. three hours later, head back, go to fire up your silent thunder and (click). If you are charging using a solar panel, figure on at least two sunny days to charge up your panels, because if you undersized your battery needs to save money, you also cheaped out on your solar panels. So no sailing for Saturday, and Sunday is out too.

There is no free lunch, and the cheap lunches are always tempting, but rarely tasty.


----------



## Mark F

Again, I have run my 48 volt motor at a 20 amp draw for a speed of 4 knots for over 7 hours. That was part of a 92 amp hr (group 27) bank. At the 7hr mark I accelerated to full throttle and achieved my normal top speed. If the batteries were drawn down too far I would not get full acceleration.

Cool, I think you will be fine with 100amp hrs for the auxiliary performance you are looking for but I would add a second bank for extra range and redundancy.


----------



## bljones

Mark, what is the size and displacement of your boat?


----------



## Mark F

It's a 1976 Ericson 27, from the factory 7000 lbs. I'm sure It's gained a fair amount of weight over the years . Probably more important is hull efficiency - an Ericson 27 gets a PHRF rating around 225, not a slippery boat.


----------



## mitiempo

Mark
Are you saying your battery bank is 92 AH @ 48 volts? If so your numbers do not make sense. That's like saying you drew 30 gallons of fuel from a 20 gallon tank - impossible. A 100 AH battery will supply 100 AH at the 20 hour rate which is 5 amps continuous. The higher the usage the less time you will get. See Peukert's law.


----------



## dman

BLJONES nailed it.Like i tell somebody...build it and then show me and we`ll both learn something.Check out diesel subs,they have batteries for days and have very limited range,not to mention diesel engines charging up the electrical system constantly.At the best you are looking at a hybrid and having 2 systems is a colossal waste of money and maintenance.Look at things realistically...people don`t like a diesel engine running,nor do i,so i use it the same times as i would use it for an electric except charging a battery and i might use that at the same time too.If you can handle a boat well you can use an engine alot less than most you see on the water...i find it a challenge not to start it up.If you say i just need it for 3 minutes to get in or out than how much diesel are you using anyway...almost nothing,sounds green to me.Then someone said if you are out in the middle of the ocean with no diesel you can always recharge your electric motor batteries...yeah and how many days would it take to charge and how many miles would you go before you were in the same situation...you wouldn`t be much further.Its pie in the sky folks for any practical cruiser and with excess weight any racer either.I find them good on the back of the canoe or a trolling motor for your little fishing boat.Then there is a thing about grounding a boat in the mud somewhere...as your battery dies down trying to free yourself...or trying to tow someone else off...hey bud..i`d like to give you a tow off the mud there but i can`t afford the battery loss.I don`t think that would go down to well.


----------



## AKscooter

*swedish guests*

If I ran out of electric power with two lovely swedish sea lasses aboard....I would whip out my oars and show them my muscles.

/One must have priorities!:laugher


----------



## bljones

LOL. Go ahead, try rowing an Islander 30, and see how impressed Inga and Jenga are... after you start panting and wheezing after the first five minutes. With an 8' beam and 2' freeboard, figure on needing at least 12' long oars- good luck storing those bad boys.


----------



## Mark F

Whatever Brian. I have no reason to lie. This has been my real-life experience.

Mark


----------



## mitiempo

I am not suggesting you are lying. But your numbers are wrong, either in reading the 20 amp draw or the bank size. Because you can't get a quart out of a pint sized pot. If the bank is 92 AH as I understood you to say, even forgetting Peukert, 20 x 7 = 140 and not 92. With this kind of illogical testimonial electric propulsion becomes even less credible.


----------



## COOL

bljones said:


> Pick up the chicks, motor off the mooring,


Once the 'entertainment' has been acquired,
an 'unexpected' lack of propulsion is part
of the plan.


----------



## Mark F

"...your numbers are wrong"

"With this kind of illogical testimonial electric propulsion becomes even less credible."

Maybe my battery monitor is wrong. But 7hrs at 4knots and current still in the bank... I was there.


----------



## mitiempo

Is the bank only 92 AH?


----------



## nickmerc

Everyone is naysaying electric propulsion. As far as I can tell the only objection is power storage. So, with all of the other benefits might it be worth working on a way to improve storage? If the same amount of resources that were put into computer research over the past few decades were applied to electrical power storage I think we would quckly take care of the issue. Many technologies we use now every day were thought to be a waste of time and insuffient for thier purpose. One major example, PDA's. Who remembers the Apple Newton?

More power to you (pun intended) and keep us posted.
________
WASHINGTON MEDICAL MARIJUANA


----------



## dman

When it comes to building this stuff why is it the people who do know how to do it don`t, but the people who are trying to figure it out do.Well they don`t really build it either after they learn.Power storage is a major problem and so is producing enough energy that doesn`t go through a power cord which is connected to a power grid.It takes one hella of windmill/solar panel to produce any reasonable amount of power to run a boat for propulsion and all the rest of equipment if you want to travel away from the power plant.We all think it`s science that will enable us to do this,i say science is stopping us...science is still working on beating a larger square peg through a smaller round hole.You can work on a formula to try and get the square peg to work or just use the round one.


----------



## tomwatt

I for one am not naysaying it... but I'm not plunking down a bunch of change in a direction that I can't easily reverse and not getting desired results, either. I'm working the math, listening to others (ok, some of that is reading not listening), and researching. Right now, I'm seeing a huge piece of weight in the boat devoted to battery-banks in order to be able to get Inga and Jenga aboard, and get back out to the happy place. Of course it might aid my argument that the 2 ladies will have to leave their bikini tops behind (did I just write what I was thinking?) because of the fear of overload!
At some point we may see a battery technology leap forward that changes the game dramatically. Most "older" folks can remember when the average charge on a flashlight battery was about 2 hours and then it was toast.


----------



## dman

I`m waiting for the solar powered bilge pump to come on after the batteries are killed.


----------



## COOL

dman said:


> When it comes to building this stuff why is it the people who do know how to do it don`t, but the people


Perhaps in theory, electric drives can not work well.
But in practice they actually do.
Parts of the discussion here echo the same arguments
people had against electric cars. As it turns out an 
electric car would work perfectly for the way a majority
of people truly use their vehicle most of the time.
I believe the same holds true for auxiliary sailboats
as well. 
There are thousands of 28-35' boats, in marinas
all all over, that have 40 year old A4 engines that are 
gasping their last breaths. Many of these boats are 
good candidates for repowering with electric propulsion.
If your boat is in a marina with available shore power,
a minimalist system such as I plan to install will work
just fine for daysailing and racing.
If you frequently motor for hours at a time, you will
need to add a Honda gas generator and an extra battery
bank and then you are good to go. Electric drives are not
anything new, they were in cars and boats more than
a century ago.


----------



## dman

You`re right they aren`t new..thats why we chose a better route when most never were tied to a slip for days on end.Yeah they work great if you don`t have to use them much...the reason the A4`s are 40 years old is because they did/do work.I seem to forget that most people leave their boats parked at a marina hooked to a cord...you are correct that is a good group to target for sure,there is a buyer for everything.Now running a generator to run an electric motor to turn a prop as we all know is anything but effecient but if you have the setup and are commited you have no other option.The whole electric car thing is a real stretch...you need to get the power from somewhere to run it and you need to get fuel to power the gas car.I sure would like to see every household in america plug their car in after work and watch the smoke fly.Today kids think of electricity as green,nevermind a coal fired plant is feeding it to them,windmills/solar are lucky to make a couple of percentage points.So the theory is if you don`t go far from home it will work for you...and i guess most don`t.


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## mitiempo

I can see electric working for someone who weekend sails and plugs in the rest of the time, using the drivetrain sparingly. This would work in some areas. But if you have a gas generator for charging there's no way you're close to green in my opinion. Between the battery manufacture and recycling, and buying and using a generator plus the aformentioned post about how the bulk of the electricity is produced you would probably pollute more overall than someone using an A4 or older diesel.


----------



## dman

mitiempo I agree 100%...We are trained to think of things as clean if they plug into a wall...look no fumes.One major problem is "we`re only going out for a little while" heard that before...of course some event that wasn`t in the plan rears its ugly head.Maybe its just me,i`ve been working on machinery for 30 years and even worked in the old mans machineshop when i was 10 machining parts,selling something to me isn`t like selling to the general public.Stop having a boring salad,stop having a boring life,you getting this camera guy...you know we can`t do this all day...bacteria in the food,you don`t want bacteria in your food,trust me....call now


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## bljones

COOL, electric cars do not work well in practice either, except in urban environments, where it is more practical to take mass transit anyway.
Let me rephrase- except in WARM urban environments. If you want to really shorten the range on an electric car, add a heater. 

But hey, it's your boat, your money, your time, your effort.

Just out of curiosity, not that this will happen, because I know you have thought of all the answers and have planned for this contingency, but just, what if, you find yourself out on the return leg from a trip to Catalina, the barometer is dropping, the wind is picking up, really picking up, you want to get in to port like, NOW, and you have no charge? If I run out of fuel on my boat, I can call Seatow or BoatUS and get a jerrycan of diesel or gas and be on my way.
Are they gonna bring you out a bank of batteries?


----------



## tomwatt

bljones said:


> If I run out of fuel on my boat, I can call Seatow or BoatUS and get a jerrycan of diesel or gas and be on my way.
> Are they gonna bring you out a bank of batteries?


No, but for $x per mile they'll throw you a rope and pull.

It seems Cool has laid out the scenario for his electrics to work, and is satisfied with that... whether or not everyone agrees with his contingency planning.

For myself, I don't see any way electric would allow for any significant movement along the ICW, for instance.


----------



## dman

I use my diesel engine for generating power to charge the batteries,and guess what it can actually turn a prop at the same time to move the boat as well.Oh i forgot...to take a hot shower as well.


----------



## klem

As the builder of 3 electric cars and 1 hybrid I feel obliged to chime in here. Electric motors are great but the energy storage associated with them is not as stated in this thread. Figuring out range is actually quite easy since each component has a rating that is actually pretty accurate. The biggest problem is figuring out how much power you are going to output and this is a function of the user, the vessel, and the conditions. Batteries have an Ah rating and you shouldn't count of discharging more than around 60% on a regular basis. If you are in a cold climate, you need to take the reduction in capacity into effect. Your controller will be around 95% efficient and your motor will be around 90% efficient. Given these numbers, it is quite easy to figure out your range with a given setup. I did a calculation for a 35' boat where I assumed that they would need 10kw continuous for 2 hours and found that they would need 18 Trojan T-105's if I remember correctly. The easiest way to cut the number of batteries would be to cut the power in half and motor at a knot or two slower. The trouble with doing that is that it would only work for very calm conditions.

Besides storage, the other difficulty with electric is charging. Fuel is incredibly energy dense so we can "charge" our boats very quickly when fueling. Charging batteries takes much longer and is limited by the 30A shore power service. The 18 batteries I quoted above could be recharged in around 4 hours using the correct charger so this would mean being on a dock quite regularly. Neither solar nor wind has the necessary energy density to make a real dent in charging a system like this. It would work if you only used the motor once a month but I would hope that doesn't describe anyone here.

Making a hybrid system comes up from time to time. The hybrids that people are talking about are series hybrids which are very different from something like a Prius. The two advantages to series hybrids are that the engine can run at its most efficient rpm and that packaging can be easier due to the motor being much smaller and not needing to be right next to the engine. The disadvantages are complexity and often a higher fuel consumption. Any time you convert energy, your efficiency goes down and a parallel hybrid has many more energy conversions than an inboard engine.

Electric has its place but that is not everywhere right now. Electric cars as commuting vehicles make a lot of sense for the majority of people who have commutes under 30 miles each way. Something similar could be said for sailboats where it makes sense for the daysailors and short distance people. The biggest danger of electric to me is running out of power when you are really counting on the motor. This is most likely to happen to someone in storm conditions. People with electric should make sure they have a different way of weathering a storm whether it be with storm sails or good ground tackle.

Whether the system is even greener is another debate to look at. Things to consider are embodied energy in the components, energy used to power the components, and disposal of the components. I would guess that an electric system has less embodied energy than an internal combustion engine but I am not sure on it. The electric system does have a better overall efficiency (our cars get 2-3 times the overall energy efficiency of the comparable gasoline ones) but it does still gets its energy from a powerplant. A cleaner (although noisier) alternative to electric would be to burn 100% biodiesel in a diesel engine.

You would be hard pressed to make a case for electric on environmental or performance grounds but you could argue for it because it is so quiet or if you were able to buy energy from a renewable source.


----------



## COOL

mitiempo said:


> But if you have a gas generator for charging there's no way you're close to green in my opinion.
> you would probably pollute more overall than someone using an A4 or older diesel.


This is pure conjecture on my part, as I have
no personal practical experience yet.
But I would have to believe that a Honda 3K gas 
powered generator, consuming 1/4 gal/hr, assisting
an electric drive will be more fuel efficient and 
produce less emissions than an A4 in peak condition.
The A4 that was in my Islander 30 burned fuel at an 
astonishing rate, while belching exhaust, all to push
the boat at a bit over 5Kts. The 6HP 4stroke outboard
that replaced it pushes the boat as fast at less than
1/2 gal/hr. My A4 was obviously in far from peak form,
but these days most are.


----------



## Mark F

It's funny how people that do not have an actual electric propulsion system in a boat can analyze a working system into fantasy . Oh well.

Klem, It's good to hear from someone that has so much experience with other forms of electric vehicles. I applaud your efforts. Your example of a 35 foot boat needing 18 6volt batteries, I think you meant 16 for two 48volt banks, that's 450 amp hrs. You will get way more than 2 hrs motoring with that setup. If you use full throttle you will use up battery charge fast but you won't go much - if any faster than at 3/4 throttle. I'm sure with the system you were designing that boat could motor all day at 4 knots and have plenty of power left.

Electric isn't for everyone, but for me, staying within 100 miles of home and being able to plug in at the slip most of the time, an ICE doesn't even compare. 

Bye now.


----------



## mitiempo

COOL
If you read my entire comment instead of just part it makes sense I think. If like most your electricity is not too green, and the batteries and their production/recycling is taken into account, plus the manufacturing of a generator that wouldn't normally be needed plus its usage, I think an A4 rebuild or rebuild of an existing diesel if that were the case would be as green. Just as with cars, when you change to a "greener car" it has to be produced and the old recycled as well. I think much of the green movement has more to do with feeling good about this than really being green. If you really wanted to be green you'd walk, sail, row or ride a bicycle.


----------



## tommays

I can say for sure you need 4HP with a GOOD HIGH THRUST prop to move and 8000# boat in the 4 to 4.5 knot range as i have done it to rescue one

I would think you would need this much power from and electric motor with one of the bigger issues being you will not be able buy a specfic HIGH THRUST as there not made for inboard shaft drives due to the drag when sailing

That puts the = electric at 3 KW as a bare minium with about a 60 amp draw with 20 amps only allowing 1 KW of thrust

Please feel free to correct my basic thinking of the required electric load


----------



## COOL

mitiempo said:


> COOL
> If you really wanted to be green you'd walk, sail, row or ride a bicycle.


I can live with that.


----------



## tommays

I rode a bike to work for YEARS and the record was using a car 5 days in 18 months for a single person trip 

It cost much more money to ride the bike in FOOD DOLLARS than GAS DOLLARS cost in the car


----------



## COOL

I know what you mean, I rode a bike as
a primary form of transportation for a decade.
I would often eat 5 or 6 plates full of food at an
all you can eat salad bar.


----------



## tomwatt

"Consuming" vs. "Belching"... seems like interesting choice of modifiers since they provide an emotional basis for viewing the nouns they describe.
Having worked with some engineers on a heat exchange system, I can guess based on their experience that converting fuel to electricity to then use the electricity for propulsion is not as efficient in general as converting fuel directly to propulsion.
To confirm the great benefits of using a generator, you'd have to work out how much fuel it requires to generate the propulsion power required compared to the engine burning fuel directly for propulsion.


----------



## COOL

tommays said:


> That puts the = electric at 3 KW as a bare minium with about a 60 amp draw with 20 amps only allowing 1 KW of thrust
> 
> Please feel free to correct my basic thinking of the required electric load


I think your math follows what I was calculating with my
feeble understanding of Ohm's law.
On Mars a 3K gen set will be putting about 60A into a
48V bank. Here on Earth I'm sure there will be a host of
misc inefficiencies along the way. But I have read where one
gentleman claims to draw about 30A at 4Knts on a 
system that is pushs a 11,000lb boat. I think such a
system is feasible for long range voyaging, especially if
you add some solar and re gen capability. It has already
been demonstrated to work in real life examples.


----------



## sailingdog

I'd point out that I clearly said that for a cruising boat, electric propulsion does not make sense. For a limited use daysailor, which has good access to shore power and can rely on it to charge the battery banks between uses, electric propulsion may make sense. But, I wouldn't count electric propulsion as necessarily being "GREEN" as the overall pollution and costs to the environment are fairly high—battery production and disposal, electrical generation costs, etc..


----------



## COOL

sailingdog said:


> I'd point out that I clearly said that for a cruising boat, electric propulsion does not make sense.


You can state that repeatedly, and still not make it true.
If there are several known examples of people cruising
around the planet in engineless sailboats, then it is certainly
possible to do so in a sailboat with limited but renewable
powering capacity.
ICE engines are far from being completely reliable. There are 
cruisers stranded in nearly every port on the planet with mechanical
problems, or drifting at sea with an engine disabled by bad fuel.
As soon as fuel prices approach $5/ gal again, I think there
will be rapid development in electric drives.


----------



## mitiempo

COOL
In Canada our prices for both diesel and gasoline are both close to $5/gallon, at least our gallon anyway. And I don't see an electric revolution around here.

As far as a voyaging boat regenerating power while cruising I'd love to see some examples complete with cruising speed, amperage draw while at that speed, battery bank size, and most importantly how many hours of generator running to make it all work. I doubt all but the most basic boat can cruise on less than 40 or so AH/24 hours and that doesn't include refrigeration. So whatever charging is done, whether solar or by other means, that amount has to be stored before the propulsion system gets its amps.


----------



## tommays

Its been done with the Lagoon 420 Hybrid no need to wonder and the word is people had to run the carp out of the gen set

can run "silent" for two hours.


----------



## mitiempo

That is what I thought. But if you have a conventional diesel engine, in other words a propulsion system that doesn't require a large battery bank, you can cruise long distance with solar and/or wind gen and never run the engine except for entering a harbor. And this will give 100% charge as opposed to the 80% you're limited to with alternator charging for sanity. One of the moderators (cruisingdad I think) gets about 200 AH daily with his solar array and I plan on being totally independent of engine running with solar as well when cruising long term. I can't think of many who would be thrilled to run a generator long hours to have "electric" propulsion.


----------



## COOL

I must concede that my assertion was incorrect,
if your idea of a cruising boat is an aquatic version of
a penthouse apartment with all the modern inconveniences
and a flat screen TV on every wall, I mean bulkhead.


----------



## mitiempo

Still no real numbers from the pro electric side for a long distant cruiser. Show us in real terms how it would work.


----------



## dman

I don`t think it is him that has an aquatic penthouse,it will be you, tied to a slip with a power cord running your show.You`ll spend more time fueling(charging) and he`ll be wringing out more saltwater out of his socks than you`ll be sailing over.


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## sailingdog

Yes, they're sailing in engineless sailboats, but having an electric propulsion system is not the same thing as sailing in a boat without an engine. The weight, complexity and unreliability of an all-electric or electric hybrid system makes it less than desirable for a long-distance cruising sailboat.

Internal combustion engines are far easier to diagnose and maintain than the more complex gear required for an electric drive system that has things like regenerative charging under sail.

Please name one long-distance cruiser that is using an electric drive system. I'd point out that Nigel Calder and his electric drive Malo aren't going to make the cut, as he sold the electric drive boat due to issues it was having...and is currently back at the drawing board.



COOL said:


> You can state that repeatedly, and still not make it true.
> If there are several known examples of people cruising
> around the planet in engineless sailboats, then it is certainly
> possible to do so in a sailboat with limited but renewable
> powering capacity.
> ICE engines are far from being completely reliable. There are
> cruisers stranded in nearly every port on the planet with mechanical
> problems, or drifting at sea with an engine disabled by bad fuel.
> As soon as fuel prices approach $5/ gal again, I think there
> will be rapid development in electric drives.


----------



## COOL

sailingdog said:


> Internal combustion engines are far easier to diagnose and maintain than the more complex gear required for an electric drive system that has things like regenerative charging under sail.


In my experience, which at this point is in the ICE realm,
this is is not true.It takes a multitude of specialized tools
and spare parts to keep a diesel or gas engine running.
Many engine repair tasks require exceptional strength.

There will be four basic components to my electric set up.
A 48V motor, 58lbs
A motor controller
A bank of 4 G31 12V batteries 4 @ 58lbs
A 48V onboard AC charger 26lbs
Other than basic battery maintenance these
systems should require no attention. If there is a problem,
most likely the controller, no single component weighs
more than 60lbs. The entire motor kit costs $1200 so
it is possible to carry an entire spare system aboard.
There are hundreds of Duffy electric boats, some of which 
have been scooting around trouble free for decades.


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## bljones

COOL, there is NOTHING on a Yanmar or Atomic 4 engine that cannot be repaired with a socket set, a hammer, a pair of snapring pliers, a drift, a set of screwdrivers and some very basic measuring tools. The total cash outlay for all of the tools for all possible in-boat maintenance and repair tasks is less than $120, or less than the cost of a decent multi-meter needed to troubleshoot an electrical drive. 

To FIX that electrical drive, you still need a socket set, a set of screwdrivers, a hammer, a pair of snapring pliers....


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## klem

Regarding service, electric drive systems are relatively comparable to a diesel engine, you are just doing different things. On a diesel, you do oil changes and impeller changes while on an electric, you clean connections and check electrolyte levels in the batteries.

The difference comes when things break down. For the mechanically oriented, a diesel engine is usually simple to diagnose. On an electric, you can figure out what component is causing problems quite quickly with a multimeter but diagnosing the exact problem is often quite difficult if it is in a circuitboard. For the average Joe, this is a lot harder to work on and chances are, it is not field repairable.

Of my electrics, the problems that I have had are a blown motor bearing (my fault on building a coupler wrong), 3 melted battery posts (we run 1500A at 144V peak), 1 overheated charger (it destroyed it), and 2 problems that we could not fix in the controller without calling the manufacturer (we had to send it back once). I would definitely not call this more reliable than a diesel but we only had 2 problems that were not field fixable quite quickly. The tools are very similar except having a few small brushes and screwdrivers is necessary for the electric system and some better wiring tools.

The correct way to evaluate whether an electric makes sense is to define your need for an engine first. This means defining your use like how far you need to motor but also what you want out of it like how loud it is. Then, you can turn this into a set of quantitative specifications like power, range before refueling/recharging, max speed, noise, etc. Then, see whether a diesel or an electric system fits best. Depending on what is important to the person who does this, some people will find that an electric system fits their needs best in some circumstances. I would suspect that the group that would find this is the people who do not venture far from their dock, have shore power, have space below for the batteries, and don't like the smell or noise of a diesel.


----------



## Architeuthis

sailingdog said:


> Internal combustion engines are far easier to diagnose and maintain than the more complex gear required for an electric drive system that has things like regenerative charging under sail.


ONLY because you know the ICE and do not know E=IR.

An electric drive system is much less complex, much easier to diagnose if there is a failure, (it can diagnose itself), and much less likely to fail.

Electric drive systems can function underwater, can function in water, and do so with no maintenance for longer run times than diesel engines can last with maintenance.

Yet in practice electric drive systems are nowhere near as reliable as the diesel drive systems.

In my experience this has nothing to do with the systems themselves and everything to do with people installing the electrical systems without wanting or knowing how to do it right.

Even when they want to do it right they almost never want to spend the money to do it right. The result is failure on many levels.

It would be the same case if people had to build their own diesel drive systems.

BTW: Most large boats use electric drive systems as do most trains, and at one time most cars.


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## dman

There is a reason why most large boats use electric drives and most small boats don`t and its not about fuel effeciency...With a small city of people that will demand power an alternator running from a diesel engine isn`t going to cut it,so they run massive diesels to run generators to provide it.Then with multiple props it is easy to put electric drive for each without having to run shafts a great distance...as well as thrusters all around the vessel.The small boat has a very short run to the prop for the engine and a small alternator will do the job keeping the batteries topped up for most folks.Now this whole train thing is another deal...try and start a train moving with 100 cars with a direct drive deiesel...don`t you think you are going to dump the clutch and run a 18 speed ...you need maxium torque for a short period to get the thing going...electric motor does this very well.Electrical systems that are having problems..... diagnosing themselves...just like when you plug into your car after the check engine light comes on with the diagnostic code reader...it aint that simple.Bad grounds and a host of other things give conflicting feedback...this is what seperates a good technician from your backyard hack.Being capsized in a boat with a crap load of batteries over your head might be concerning on top of the obvious problems.Anyone consider a lightening strike?


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## mitiempo

I think it has been established that electric won't work for offshore cruising without a major revolution in battery technology. But even for those who daysail where it will work effectively the only systems that make sense to me use a conventional shaft and stuffing box. The units like the E Pod that hang the motor in the galvanic mix below the boat lose for both corrosion and drag reasons I think.


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## dman

The way this thread was heading with efficiency it was about to change my way of thinking.I was going to plug an electric motor into the wall to turn a generator to produce electrical power to sell.


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## sailingdog

Actually, I do know E=IR fairly well, having been trained as an electrical engineer and working as an engineer in the IT field for over 20 years. A primitive electric drive system might be easier to diagnose, but the more complex systems that offer regenerative charging and such certainly are not.

The more "green" the electric drive system, the more complicated it is going to be to diagnose and repair. Features like multiple charging systems, regenerative charging, etc., are going to make things far less simple than the typical small boat diesel, which only requires FUEL, AIR and cooling water...

The typical diesel engine on a small sailboat doesn't require much of an electrical system and can run without any electrical system once started, since they generally use mechanical injection and the only real electrical dependency might be an electric fuel pump. The small four-stroke and two-stroke gasoline engines are scarcely any more complex.



Architeuthis said:


> ONLY because you know the ICE and do not know E=IR.
> 
> An electric drive system is much less complex, much easier to diagnose if there is a failure, (it can diagnose itself), and much less likely to fail.
> 
> Electric drive systems can function underwater, can function in water, and do so with no maintenance for longer run times than diesel engines can last with maintenance.
> 
> Yet in practice electric drive systems are nowhere near as reliable as the diesel drive systems.
> 
> In my experience this has nothing to do with the systems themselves and everything to do with people installing the electrical systems without wanting or knowing how to do it right.
> 
> Even when they want to do it right they almost never want to spend the money to do it right. The result is failure on many levels.
> 
> It would be the same case if people had to build their own diesel drive systems.
> 
> BTW: Most large boats use electric drive systems as do most trains, and at one time most cars.


----------



## klem

I have to agree with Sailingdog about electric being harder to diagnose. Like him, I am an engineer and I have a lot of experience in working on electric drive systems. With a diesel, most diagnosis is done by sight (looking at exhaust), sound, and smell. On an electric, the most common part to fail is the controller which has a couple of complex circuit boards which are extremely hard to diagnose without a wiring diagram, a calculator and lots of patience. If you carried a second controller that you could swap in, it might not be hard but controllers really are not field serviceable.


----------



## COOL

mitiempo said:


> Still no real numbers from the pro electric side for a long distant cruiser. Show us in real terms how it would work.


I'll take a stab at this.
The boat that I am installing the electric propulsion in,
which is my custom Lancer 36, not my Islander 30, is not
likely the boat I will take on my world tour. But assuming 
we had to get out of here, this is a hypothetical set up.
It seems to me this is feasible.
Aside from the 4 batteries dedicated to the e motor, I
would add two additional batteries to the house bank so
that it could also be configured to 48V to power the
motor. Even with six batteries dedicated to the motor,
the entire system still weighs less than the 500lb diesel.
The motor can run on 24V as well. 
I would carry 4 solar panels that could be linked to charge 
the 48V bank,or linked up in a way to charge one 12V battery 
at a time at a greater amperage.
I would also have some ability to charge from re gen from
the prop while sailing, which would be almost all the time
on a passage. So there would be days on end to refresh 
the bank.
Day after day of motoring would not be possible unless
a fossil fuel generator were added. But guess what, I have
done five passages between the mainland and Hawaii, and
one to Tahiti. And no boat, that sails well, has the capability
to motor for more than few full days on such a passage, even with
fuel jugs lashed all over the deck. Some fuel has to be reserved 
to run the engine for charging, which is less efficient than 
running a small dedicated gen set.
While coastal hopping I would likely be stopping at a marina
here or there for a full recharge, not unlike the motor sailors
that power from gas dock to gas dock.
Sorry, but I have made no calculations to support my
hypothesis, but am making guesstimates based on the
experience of others.
Tear it apart.
Mas Rapido.


----------



## Architeuthis

sailingdog said:


> Actually, I do know E=IR fairly well, .


.

Not you, you but you people who think Electric drive are complex. Recall your motor class, what did you need to get the darn thing turning, almost nothing. People talk about complex control systems but recall the one you built, how many moving parts did it have? You can count them on one hand. You can make a control for a basic system with little more than a few light bulbs and in a pinch you do not need even that.

How many moving parts in a basic ICE? You see my point.


----------



## Architeuthis

klem said:


> I have to agree with Sailingdog about electric being harder to diagnose. Like him, I am an engineer and I have a lot of experience in working on electric drive systems. With a diesel, most diagnosis is done by sight (looking at exhaust), sound, and smell. On an electric, the most common part to fail is the controller which has a couple of complex circuit boards which are extremely hard to diagnose without a wiring diagram, a calculator and lots of patience. If you carried a second controller that you could swap in, it might not be hard but controllers really are not field serviceable.


Really? Of course you have a second controller, just as you have a second injector or ECU and just like a failed injector you can bypass the controller if needed.

Of course it starts at design, if you want a complex system that gives you the most power then yes it can be tricky to bypass but the same is true for a modern diesel. If you cannot troubleshoot a motor controller you will not be able to troubleshoot an ECU. Apples and apples please.


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## dman

The funny part of this is the crowd that says a diesel is more complex than an electric setup,noisy,more maintenance but they will have one to charge the batteries.People are mixing up electric motors and battery powered electric motors.Trains,large ships and such are apples to oranges in this discussion,it just adds to confuse the issue of running a battery powered electric motor.I have a 550 pound 40 hp electric motor in my shop to convert my single phase incoming power to run 3 phase equipment.I`m all for electric motors when the power source is practical,my power comes 50 miles away and the smokestack isn`t in my yard.Anyone here like to use a battery powered stick welder and see the amount of battery that is required to run a 180 amp bead or throw a quart of diesel in the engine powered welder and see what that will do.I don`t even need to calculate anything,someone with a minimal amount of practical working experience already knows the scoop.


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## sailingdog

I'd point out that the ICE, especially a small boat diesel, is actually a very primitive and simple beastie. Almost all of the technology in it is "caveman" technology and while mechanically somewhat complex, it is actually very easy to maintain, troubleshoot and repair, using a relatively simple tool kit.

The electronic components of an electric drive system are going to be more complicated, since you'll need some sort of motor controller to handle the throttle function on all but the most basic system. These electronics are far more prone to failure in the wet, salt-laden environment than is a marine diesel engine without electronic fuel injection. Such a marine diesel engine, with a snorkel or elevated air intake, can actually run while partially submersed... which is not the case with the electric drive system components as a rule.

Troubleshooting complex electronics aboard a small, wet, sailboat is going to be far more difficult than troubleshooting a diesel in the same conditions. Troubleshooting the complex electronics of the motor controller and any regenerative charging system is going to be beyond that of most sailors I know-where troubleshooting a diesel is not. Also, the spares for a diesel system are far less likely to become damaged prior to them being required, since they are generally far more rugged than the backup electronics needed for repairing a motor controller would be.

This doesn't even begin to address the issues about run-time capacity and the inability of an all-electric system with no diesel genset to recharge the system properly so that the batteries don't die from neglect. It is very easy to deeply discharge batteries using an electric drive setup, and much more difficult to keep the batteries properly charged if you are to avoid using and having a diesel genset aboard. *If you're not going to avoid having and using a diesel genset, why add all the complexity of the electric drive system to the boat-since operating and maintaining the diesel genset requires all the skills of running an inboard diesel.*

Again, the requirements for a cruising boat and a daysailer are very different. I am addressing the viability of electric drive systems on a cruising boat specifically.



Architeuthis said:


> .
> 
> Not you, you but you people who think Electric drive are complex. Recall your motor class, what did you need to get the darn thing turning, almost nothing. People talk about complex control systems but recall the one you built, how many moving parts did it have? You can count them on one hand. You can make a control for a basic system with little more than a few light bulbs and in a pinch you do not need even that.
> 
> How many moving parts in a basic ICE? You see my point.


----------



## Architeuthis

As already mentioned cruising boats do not need engines to begin with as they are so rarely in harbor. Motorsailors are a different breed and that is what most of us have and use but first: 

You are still comparing the "simple" diesel to some complex AC Electric drive. When you do that you can get it to appear that the electric drive is less reliable (not true) but even that is due to people knowing ICE and not E=IR. 

The "simple" diesel is a very complex machine, with hundreds of moving parts. 

A simple electric drive has less than a dozen moving parts, if we include the commutator.

When it comes to complex the diesel is going to lose every comparison to an electric motor because almost all of them have an electric motor to start. When you think about it the diesel is no more reliable than an electric motor because it depends on one to start it's even more complex process. 

I would also take issue with the idea that troubleshooting an AC drive controller is too difficult for the average sailor. Actually no I don't if that average sailor is not able to troubleshoot a diesel system, then it is too much but if they can do that they can certianly deal with an AC controller. 

The reason for that is they simiply unplug it and plug in the spare. 

I also wonder why you think these systems have to be so fragile. I suspect that is due to the ICE not I=IR issue I referred to. If you were more familiar with these devices you would know that they are much more rugged than any diesel engine. 

It takes little effort, yes some but not much, from the design stage, to make the system waterproof and rugged. Flood the engine room of a diesel and it will take more than just draining the water to get the engine to run. A properly designed and installed electric drive system could just continue to run while under water, even saltwater if one wishes. 

The reason they don't is in part that is not needed, people are not familiar enough with the systems and the ones doing it now are always picking the cheapest solution and taking way too many short cuts. 

As you and I have pointed out, such systems often die of neglect, which IMO is a design flaw. A really good system needs little mtce and if totally ignored would protect the batteries from damage. 

Since people are putting it on the table I guess I'll point out that I have troubleshot complex electronic and computer circuits in conditions that make the engine bay of my boat look warm dry and comfy. In at least one case it was a drive controller for a motor, mind you a bit bigger than our sailboats could use but still actual experience. 

In another case our in house designed and built control board had to be installed in very wet conditions in a water control structure. Being 100ft under water the concrete was constantly wet and water rained continuously from the ceiling. If the pumps shut off the shaft would flood and it had been flooded before. The electronics showed up in a normal metal box, a quick WTF resulted in a really nice fix. Waterproof fittings were installed on a pelican type case and the board installed in the case on springs for shock protection (they were already in the case so why not). 

Was it really waterproof? An on site test had the case under water for a day and not a drop got by the connectors or seals. We can make these systems rugged enough to drop to the bottom of the ocean or sit on the surface of the moon, something a diesel cannot claim. 

As to why someone would want a diesel electric drive? For the same reason these are the most common drives on most large boats. They supply lots of electrical power for onboard systems, and are the most fuel efficient when a variable speed drive system is needed. 

And they are as reliable as you want, or rather are willing to pay. I don't have one on my boat because they are expensive to set up and as this thread shows lowers the value of the boat because people do not understand them.


----------



## Architeuthis

dman said:


> The funny part of this is the crowd that says a diesel is more complex than an electric setup,noisy,more maintenance but they will have one to charge the batteries.People are mixing up electric motors and battery powered electric motors.Trains,large ships and such are apples to oranges in this discussion,it just adds to confuse the issue of running a battery powered electric motor.....


There are multiple issues in this thread but it shouldn't be confusing.

The pure electric drive system would work very well for a cruising or passagemaking boat. There is easily enough room in your average passagemaker for enough batteries to get you in and out of even large harbors, I think that has been shown in this thread. For larger harbors they would go old school and get a tow in and out.

These pure electric systems can be very simple and very cheap which is why they were the first drive systems for cars. I'd recommend the exact same controller too. Very cheap, rugged, and easy to fix.

Those wanting to motorsail as it appears you do, and I certianly want that, cannot use the pure electric system, hence the diesel electric drive issue.

Those wanting to split the difference can do so with enough batteries, solar panels, water generators, wind generators and so on.

Of course the cheapest system is an ICE drive and maybe a gas generator to charge the batteries at anchor so that is my choice.

I know my Dad would have none of this discussion. He thinks that real sailboats do not have engines. LOL


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## tommays

In the nicest way your writing a popular science article of the future on what could be and ignoring the electric products on the market problems with cost and lack of success.


There is a full line of Torqeedo outboards 

Battery supply:
The Cruise 2.0 R requires a abttery voltage of 24 V, the Cruise 4.0 R requires 48 V. We recommend a battery supply of batteries with at least 180 Ah capacitiy each. Lead-based batteries are not resistant to high current, i.e. the capacities indicated on the casing are not available when the batteries are to be fully discharged in a short time (e.g. 1 or 2 hours). For this reason, you should allow for sufficient reserves. Alternatively, the Cruise 2.0 R can also be run with at least one lithium-manganese battery from the Torqeedo Power series. The Cruise 4.0 R can be run with two batteries from the Torqeedo Power series


----------



## braidmike

We are not cruising yet...  But hopefully very soon. Some real numbers on a pretty simple system: a 60VDC electric outboard from Ray Electric rated at 5HP (electric) pushes a 35' Ericson (13000#) at 3kn in a protected calm harbor at 20amps. increasing speed to 4kn increases load to 35-40amps. Hull speed (6.5kn) 'can' be reached (did twice in testing ) at 120amps. Storage system is 10 Trojan L16HC 6VDC 415AH batteries. The batteries are amidships in the bilge adding 1000# to the ballast. These are real world figures. Theoretically, the range is 10 hours to 50% DOD at 3kn: 30 miles. I have never run even close to that far. The longest motor was back from the yard to the slip after having the mast pulled for refit, about 6 miles. I think the batteries didn't even realize they had been used! The beauty of this setup for cruising is the ability to switch the bank to a 12VDC house bank of over 2000AH! Keeps the beer cold while waiting for the sun to hit the solar panels. (while configured for 60V, two smaller 12V batteries power house and lighting needs) Right now, the panels are two BP 85W through a Blue Sky MPPT controller. Before leaving for a circumnavigation, we will add one more panel and an Aquagen tow-behind generator (4A @ 5kn 24 hours/day while sailing).
For all the naysayers: I understand this setup will not power me off a lee shore, cross the doldrums, outrun a storm, etc. What it will allow is easier in/out of crowded harbors, slips, and anchorages.
This type of drive system is not for the mass public (yet!). But even with todays battery technology it is possible given a few tradeoffs.
The cost: probably about the same as a replacement of the old A4 with a new Universal diesel. 
Who'd a thunk a discussion on electric drive could get as contentious as asking what anchor to use??:laugher 
Cool, just figured out who & where you are; I'm on the gangway next to you, come on over & check it out!


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## klem

braidmike,

Thanks for those numbers. As would be expected, your range is significantly better at much lower speeds. The system that I spec'ed earlier in this thread was for someone who wanted the same speed performance as a diesel and did not want to go as slow as you are willing to. I would be interested to hear how well you can keep up with your demand on your batteries. A quick estimation gets me to 100 full sun hours on your solar array to go from no charge to full charge (I am ignoring the towed generator and house loads). Around here, even in the summer you are lucky to average 6 sun hours a day but in the tropics, you might well be able to get 10-12 (guessing) on the best days. It will be interesting to hear whether you can keep your draw on your batteries low enough for this to keep up.

I think the most important part of your post is that you understand the weaknesses of your system and know what its role is. You clearly are not looking for a system that can run at full power for many hours in rough conditions, you have other ways of dealing with that. I think that a lot of the debate in this thread is with regards to what the system should be capable of doing and since you are not looking for a system for storm conditions or prolonged calms, you seem to have a well designed one for your use.

Good luck and thanks for the real world numbers.


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## hfmckevitt

*help with electric motors*

I am very interested in installing a electric motor in my S2 9.2C, however I sail on the west coast of Florida and from all I have read the electric motor would not be a good ideal for anything but as lake. I could use all the help you have to offer. 
Thanks
Henry


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## mitiempo

The electric option works if you have shorepower at your dock for recharging and don't power excessively. For longer trips away from shorepower charging it isn't so successful.


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## mszczepa

There is a boat in Seattle that has a 3.5 kw gen that will power his electric motor at half speed he used a battery out of a prius as his battery for the electric motor


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## P35juniper

Ok, I have some electric drive time under me, Elec-Trak and forklifts, I am intreged by parralal hybred with an engine and motor on a common shaft.
But for the sieres hybred if you run a small genny while running of the batteries your range is way more then just batteries and if you are using a sieries wound motor at say 15HP cont. you also have the ablity to have controllers at 60HP and have way more power for a few minutes, say when the water gets a bit thin.
And if you add solar and wind you could have some renewable "fuel" as long as you don't need much. 
As for batteries needing to be replaced offer, NaFe batteries last about 50-100 years, and for emergence use, you could get some zinc/salt water batteries, they are one time use/replace the zinc and have a higher power wieght ratio.
But for now, I'm keeping the Yanmar 3GM30F, 30 gallons is 30 hours WOT and alot more a bit slower, 1000rpm is 4Knots, 3200rpm is 8Knots.


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## Winggy

*Very cheap, rugged, and easy to fix*



Architeuthis said:


> ... These pure electric systems can be very simple and very cheap which is why they were the first drive systems for cars. I'd recommend the exact same controller too. Very cheap, rugged, and easy to fix.


I'm building a 62' biplane rigid wing catamaran, intended to use series hybrid drives for motor-sailing and harbor entering/clearing. I have the motors and motor controllers (2+ a spare), but am still concerned about a controller failure, computer failure, etc. You mentioned the control system for the original electric drive cars was quite simple. And, I am fairly confident that they did not involve any semiconductors . I like "...cheap, rugged, and easy to fix." Can you please point me at a resource for more technical information? Thanks.


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## P35juniper

Winggy, all you need is a few big contactors and a bit of big nicrome banding, to slow down how fast the motor runs, if you start full power it would likely rip things apart quickly, look at old golf cars for how they work, not the newer ones


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## Winggy

P35juniper said:


> Winggy, all you need is a few big contactors and a bit of big nicrome banding, to slow down how fast the motor runs, if you start full power it would likely rip things apart quickly, look at old golf cars for how they work, not the newer ones


OK. Thanks. Now, go slow with me because I'm old and my mind is feeble, but... isn't nichrome wire noted specifically for it's resistance and aren't you therefore suggesting a voltage divider that burns off a fair amount of my precious...?


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## casioqv

Winggy said:


> OK. Thanks. Now, go slow with me because I'm old and my mind is feeble, but... isn't nichrome wire noted specifically for it's resistance and aren't you therefore suggesting a voltage divider that burns off a fair amount of my precious...?


You need a digital switching motor controller made to marine specs, not a big resistor. Perhaps your only option is to build a rugged waterproof enclosure for one designed for cars. Maybe mount inside a pelican case?

The large digital trolling motors like the Motorguide 82lb/24v I use on my Catalina 22 have the controller totally encased in a block of epoxy. I don't know how heavy your boat is, but perhaps you could look at commercially available digital trolling motors also.

The motorguide one has a nice feature that it gradually ramps up thrust- so I can switch it on at full throttle and it gets the boat up to speed quick, without a hard jerk.


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## mtboat

*electric sail*

Would someone like to look these over and comment?
Vetus electric motors.


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## Classic30

mtboat said:


> Would someone like to look these over and comment?
> Vetus electric motors.


Not much to comment about, really..

They are a good piece of kit (at least their thrusters are, so no reason to think these wouldn't be) and certainly the way of the future. They're just not to everyone's liking or wallet size, that's all...


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## tommays

The vetus does require water cooling which shows me they are being more realistic about the space it will be in

In Practice
During trials with a 2,2 kW electric motor in a 6 metre GRP launch, with a total displacement of 1,2 tons (4 persons and 4 batteries on board), the power consumption was 50 A (24 Volt) and have a max speed of 9 km/h. (4.8 knots) With the available battery capacity (24 Volt - 360 Ah) it was therefore possible to make a trip of 6 hours at this maximum speed assuming the batteries will accept 80% discharge. If lower speeds are acceptable, the total motoring time will of course be proportionally increased.

But thats a lot of battery in a small boat


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## mitiempo

80% discharge doesn't make for long lasting batteries either.


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## P35juniper

The Nichrome is just to buffer the start up of the motor, if you dodn't it would rip it's self apart, you would have one speed normal operation, full power, you just make sure the full power is your intened cruising speed, then you just use the resistors for the times when you need to go slow, and you can also turn it on and off ever few minutes. I ran with this type set-up on GE Elek Traks and Yale fork lifts for years, very bullet proof, 
As for running you batteries down 80% if you have real good ones they will hold up for a while if you can charge them as soon as you run them down, but you will shorten they're life, if you try it with a car battery it may last 5-10 time, with a L16 you may get 100-500 times, and Edison batteries 15-50 years(electolite will need replacement but that is just KOH) LiFePO4 seems to be promising but expensive for now. 
Has anyone thought of trying to make a hybrid diesel electric, with the electric driving the shaft when the engine is in neutral, and recharging the batteries when running the diesel


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## mtboat

*electric sailboat motor*

Ok ...I take note, 6 hrs. at 80% discharge. But here it is. I am completely without numerical skills. None, zip, zero. I understand not to drain a battery bank past halfway for the longevity. I know if I am sailing, I won't use the motor for 6 hrs. More like an hour of motor time at worst. 
Will solar panels be able to do this job adequately, or will a generator need to be in the loop? How many batteries?


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## Classic30

P35juniper said:


> Has anyone thought of trying to make a hybrid diesel electric, with the electric driving the shaft when the engine is in neutral, and recharging the batteries when running the diesel


Yes they have and it's a waste of weight for no gain. Since boats don't have brakes, unlike cars or trucks, there is little regenerative effect to be gained from recharging the batteries via the shaft.. but read on:



mtboat said:


> Ok ...I take note, 6 hrs. at 80% discharge. But here it is. I am completely without numerical skills. None, zip, zero. I understand not to drain a battery bank past halfway for the longevity. I know if I am sailing, I won't use the motor for 6 hrs. More like an hour of motor time at worst.
> Will solar panels be able to do this job adequately, or will a generator need to be in the loop? How many batteries?


IIRC, Vetus don't really have sailboat use in mind. Exactly like the hydraulic auxilliaries that have been installed in yachts since the '60s, you're expected to use a generator of sufficient size *100% of the time the motor is running*.

The primary reason for this system in the first place is that, whilst ostensibly "charging the batteries", the generator then also gives you a 110V/220V AC power system throughout the boat whenever the engine is running - for the bar fridge, microwave oven, Intelsat terminal, TV... and the generator can be put anywhere on the boat that is convenient - not just in the traditional "centre of the bilge location". The batteries are needed for motor load-handling and give you a reserve capability to "get to safety" if the generator quits.

These "diesel-electric" systems are being fitted to river launches and expensive yachts the world over (anywhere $$$ is no object!) - so, yes, they work and work well for certain applications and, no, it isn't really all that new given the technology has been around for many years now. It's only that the electronics used in the starters and the cost of the motors and batteries has become more affordable in recent times.


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## engele

There are, and unfortunately always have been some pretty intense feelings against electric power here on sailnet (despite people who have done it posting pics and first hand experience). It seems to me that everyone always argues that electric doesn't have the range. Inevitably there is a disagreement about how much range is needed, and a bunch of numbers thrown out by people without first hand experience. Rather than argue on a forum about it, I would recommend getting in touch with a manufacturer/dealer and see if they can set you up with a ride on one of their customers boats. That way you see it first hand and can decide if it's limitations and benefits are good enough. There will always be people who will trash any new idea (and even old ones they just don't understand). I have burned out on arguing with the idealists on the electric side, and the idiots who say it can't be done.

Best advice is to talk with those who have done it. I think most of them went into the decision with eyes wide open as to the tradeoffs, and their experiences are really what you should be interested in, not some armchair engineer (though we are all a bit of that).

Also I say this without directing any negativity at any of the prior posters. It just seems that people get waaaaay to emotional about this subject for some odd reason.


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## mitiempo

Electric works well for someone who day sails primarily and can plug in at night to charge. Works less well for someone who likes to anchor out for their 2 or 3 week holiday. And in some areas like the Pacific Northwest you end up motoring a lot of the time in the summer due to light or non existent winds and narrow passes.


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## P35juniper

As I was quoted above, I was looking at the power curve info from Yanmar, at 2000 engine rpm my 3gm30f can make up to about 11 HP and with the 2.63:1 gear the prop should be using 4 HP, so if I'm running along at 2000 for a few hours I could pull more power then I'm using to push the boat, then the next morning at 5AM when I leave the anchor I don't fire up the diesel, and make lots of noise, for 10 to 15 minutes to leave the harbor, I can just ghost out, if I need to run 10 hours into 40K headwinds I'll trust Yanmar.

I'm not looking to be able to go electric all the time, just be able to move for a bit without starting the diesel, I thought those big flappy things were for that, and I would also be able to use the drive batteries as more house bank.

I do know abit about electric drive on land, electric cars are not the way to go for everyone, but they are good for some, electric/fuel hybrid is better for most, fuel/electric not as much benefit, and just fuel is the way to go for some, if all you do is go back and forth a set short distance - all electric is great, if you mostly go that same short distance but go on longer trips you need an another system - electric with fuel back-up, if you mostly use gentle/slow but need power/speed - fuel with electric, if you want full power all the time - fuel only.

Batteries are the big problem. if you had a battery with the same power density as diesel, was inexpensive, and has a long life/high cycle life, then things change.


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## Mark F

Hi P35juniper,

You might want to check out Electric Yacht's Weekender; Electric Yacht - Our Weekender Hybrid Systems


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## P35juniper

Mark F 
Thanks I like that, just what I was looking for, not too bad of a price.


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## Classic30

engele said:


> There are, and unfortunately always have been some pretty intense feelings against electric power here on sailnet (despite people who have done it posting pics and first hand experience). It seems to me that everyone always argues that electric doesn't have the range. Inevitably there is a disagreement about how much range is needed, and a bunch of numbers thrown out by people without first hand experience. Rather than argue on a forum about it, I would recommend getting in touch with a manufacturer/dealer and see if they can set you up with a ride on one of their customers boats. That way you see it first hand and can decide if it's limitations and benefits are good enough. There will always be people who will trash any new idea (and even old ones they just don't understand). I have burned out on arguing with the idealists on the electric side, and the idiots who say it can't be done.


To be quite honest, the biggest problem with electric motors on sailing yachts outside enclosed water has nothing to do with batteries or charging systems which are all well developed. It is simply that high-voltage high-current electrical systems and salt water don't mix, and, AFAIK, there isn't any guaranteed way of keeping salt air (corrosion) out of the inside of a drive motor without it being both unnecessarily heavy and maintenance-intensive.

What this means in practise is that they're fine for bow thrusters and winch motors, and even for river cruising or day racing, but for something that is needed to 'get you out of trouble when caught off a lee shore in a gale', high-power electric drives require more skilled maintenance (due to the high voltages involved) than your typical Joe-Yachtie can handle.. compared to the will-pretty-much-run-under-water Diesel alternative.

It's not a case of it can't be done - it's a case of buyer beware.


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## engele

Hartley18 said:


> To be quite honest, the biggest problem with electric motors on sailing yachts outside enclosed water has nothing to do with batteries or charging systems which are all well developed. It is simply that high-voltage high-current electrical systems and salt water don't mix, and, AFAIK, there isn't any guaranteed way of keeping salt air (corrosion) out of the inside of a drive motor without it being both unnecessarily heavy and maintenance-intensive.
> 
> What this means in practise is that they're fine for bow thrusters and winch motors, and even for river cruising or day racing, but for something that is needed to 'get you out of trouble when caught off a lee shore in a gale', high-power electric drives require more skilled maintenance (due to the high voltages involved) than your typical Joe-Yachtie can handle.. compared to the will-pretty-much-run-under-water Diesel alternative.
> 
> It's not a case of it can't be done - it's a case of buyer beware.


I would love to read some reports of bad experiences with electric. So far I have not found them. If you have, please share. Like I said, most of the naysayers seem to be people who have not seen it first hand. I am about as expert as you are on this (meaning I am happy with my current diesel), but so far all of the people I have talked with who have either done it, or seen it first hand were pretty pleased. You can talk theory all day, but if you get from point A to point B, are happy with your speed and range, then who cares? It could be the perfect setup for some people.


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## engele

In any case, like I mentioned in an earlier post, it makes sense to just go check out a boat that has this type of setup if you are considering it. In this thread, the guys that did it were happy. We had an electric trolling motor on our dingy for years and loved it. They way I see it, electric drives on sailboats are just scaled up. Bigger motor. Bigger batteries. It isn't a new idea.


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## P35juniper

there isn't any guaranteed way of keeping salt air (corrosion) out of the inside of a drive motor without it being both unnecessarily heavy and maintenance-intensive.


As opposed to the 2 horse power electric motor that is bolted to the side of my 3GM30F, I don't hear too much about starter motors having problems, and if bolt a big electric motor under a car, road salt, road spray, your average drivers neglect?, then as to having the motor in the water outside the boat, my 240 volt well pump motor has been underwater for the last 20 years and still works fine. There is no real inharent engineering that at a problem,


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## Mark F

"I would love to read some reports of bad experiences with electric."

The other day I hauled my boat to do a bottom job and install a new cutlass bearing. To remove the prop shaft on my Ericson 27 you need to drop the rudder. I realized I could loosen the mounting bolts on my electric drive (SolidNav) and lift it enough to pull the shaft forward and under the motor. 

Oh wait, that was a good thing


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## engele

Mark F said:


> "I would love to read some reports of bad experiences with electric."
> 
> The other day I hauled my boat to do a bottom job and install a new cutlass bearing. To remove the prop shaft on my Ericson 27 you need to drop the rudder. I realized I could loosen the mounting bolts on my electric drive (SolidNav) and lift it enough to pull the shaft forward and under the motor.
> 
> Oh wait, that was a good thing


This is exactly my point. Mark, guys like you seem to be pretty happy, and that is even after acknowledging that you gave up some range. In your case it sounds like you are getting pretty good results anyhow though. Range, power, everything. I would also like to second the starter motor argument. My starter is a brushed motor that sits just inches from my bilge, and is very very old.


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## engele

Obviously, this isn't a solution for everyone, but I get frustrated when people ask questions and just get shot down out of hand. From what I can tell, it's a good option for some folks.


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## P35juniper

engele said:


> Obviously, this isn't a solution for everyone, but I get frustrated when people ask questions and just get shot down out of hand. From what I can tell, it's a good option for some folks.


Now thats the best way I've heard it put, there is no one size fits all.


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## COOL

engele said:


> You can talk theory all day, but if you get from point A to point B, are happy with your speed and range, then who cares? It could be the perfect setup for some people.


Your posts in this thread have all been far too reasonable.

I have our electric propulsion system up and running,
and thus far it is meeting my expectations exactly.
For slow speed maneuvering in and out of the slip,
no fossil fuel motor can match our electric.
We do not have to start the motor and warm
it up, I put it in gear it goes, take it out and the 
motor is off. We can spin the prop as slow as we want
since we dont need to rev the motor to any particular
RPM. It is not silent when running, but it is quiet,
there is no clanging and banging to rattle 
your nerves when docking and no exhaust plume
wafting into the cockpit.
The 500lb Volvo diesel gave us a higher top end speed,
and greater range certainly. But for us the trade offs
are acceptable as we have a sailboat that performs
well in a wide range of conditions and we only need the
auxiliary occasionally for docking.
An electric motor is a perfect auxiliary for the
way a large percentage of owners use their boats,
and it is a good alternative for repowering the many
boats out there that have Atomic 4s which
are approaching the end of their lifespan.


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## Mark F

Hi Cool,

It's good to hear you are up and running. You repowered a saildrive, right?

What size prop are you running?

Any photos?


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## COOL

Mark F said:


> Hi Cool,
> 
> It's good to hear you are up and running. You repowered a saildrive, right?
> 
> What size prop are you running?
> 
> Any photos?


Yes, it is a 48V set up I assembled with off the shelf 
golf cart gear coupled directly to the Saildrive leg. 
The prop is a stock Volvo aluminum 2 blade fixed, it may be
16x11 according to my Volvo literature. I intend to
change it out with a Martec folder, unless I determine
that the regen from the prop is too good to give up.
Sailing performance is much more important to me than
powering ability. With just one bank of batteries 
I really only expect to get in and out of the slip,
for that it is working really well.
I do have a good photo of my set up,
but my computer is out of brain cells and freezes up
when I try to upload a pic.


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## steel

davidpm said:


> [*]Long term costs will be higher than diesel as the batteries, a large part of the system cost, will have to be replaced every few years.


If properly maintained, lead-acid energy storage costs about 15 - 20 cents / KW*Hr. Electricity is 10 - 15 so that's * 25 - 35 cents / KW*Hr total.*

Diesel is something like 1/12 a gallon per KW*hr. At $3 a gallon that ends up at about 25 cents / KW*hr. But with electric you have no oil changes or engine ware outs. Both have their problems I guess

*But I want a coal powered boat. That way it'll cost 5 cents per KW*Hr.*


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## mgunning

Been reading this blog and am puzzled. As a owner of several boats including an Ericson with a 23hp diesel, I have not been impressed by the ICE being the answer to get me where I want to go and back home. The systems are complex (starting, cooling, gear, fuel, and electrical) and need constant attention and that is with a newer motor.
I have just purchased a Newport 30 and will be repowering it with electric. I would like to check out Cool's Islander 30 as it would be a comparable boat. I am going with the Electric Yacht 180i, 48v, 8 Trojan 125s and a backup generator with solar and wind generators later. We have scoped the system for a 30 mile range at 4.5k. It is primarily a sailboat so I am not too concerned about the range. The issue I am trying become clear on is the best prop as the electric is so much more effecient at driving the prop, especially at low rpms, and its ability to regenerate.
I am in Dana Point. If you would like to show me your Islander, you can email me at [email protected].


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## Mark F

Hi Mike,

Sounds like a good setup. It's interesting watching the industry become standardized. Electric Yacht is a good company with very good customer service. I bought a competitors product but have communicated with Scott and Bill at EY over the years and they have always been knowledgeable and helpful.


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## engele

COOL said:


> Your posts in this thread have all been far too reasonable.


Thank you Cool. Sometimes I think my opinions are unwanted on this forum. People get way too worked up about this stuff when really it doesn't matter that much.


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## Jimske

Interesting thread. Lots of good ideas. The installation must accomplish the need and if it does that then it is a success. I am thinking of putting a spin bicycle in the cockpit and using that to turn the prop. My wife spins so . . . Problem is I don't have a prop so I am going to start there.

What I want is to keep my 9.9 outboard which generates 12v for my single battery. My problem is the outboard, which is situated on a "sled" between the port ama and main hull on my SR 31 A Frame. Works fine much of the time but when I need a little more power for problem currents or headwinds when I don't feel like tacking all day to get home. It would be real nice to have 3 or 4 hours worth of "boost." And I guess that a prop deeper then my outboard prop would be better. Motor sail? Why not? Even though the SR31 will do half the wind even 8-10kn wind. 

One of the many great things about this boat is storage and access to it.

What I want is to be able to use the outboard in conjunction for the most part and use a 12v electric motor attached to a shaft and prop which I need to figure the angle and size and placement. I might use the electric motor for a few hours on it's own.

I got a funny feeling from reading all these posts that 12volts ain't gonna make it! Too bad because I thought the outboard and a 12v wind generator could help charge the batteries.

Green? It'd be nice but I don't care! My truck gets 15 mpg, my house uses oil and is not that energy efficient. I would even consider running a small electric motor off of an easily removable gas generator push comes to shove.

Money? I don't have any but my wife says that doesn't matter and I should be able to get anything I want because I want it. ;-)

Any positive comments (read no bad vibes please) will be VERY welcome.

Thanks in advance.

Jim in CT now.


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## mgunning

Well, I just installed my new electric system in my 79 Newport 30. It took towoof us to do it and it went quickly. Today, after our first test runs, we are now forecasting a bit better distance on a full charge. We went with a bit bigger battery package, 8 6v 300AH AGM's from lifeline, not cheap. Since I have two new 12v batteries for the house system, I am planning on getting two additional inexpensive 12v to produce a second 48v system with a stepdown to drive the 12v house systems (lots of blender power).
I am also looking at solar and a wind generator. Finally there will likely be a 2000w generator that will share the propane system that I will use of the BBQ and galley cooking.
I will let you know how it goes.
Mike


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## centaursailor

Read some of this thread and reckon its about were electric cars were 10 years ago.
The technology is there already but the cost/benifit is still prohibitive. 
The traditional ICE supporters tend to be reluctant to come on board but nothing new there.
A few articles have appeared on electric sail boat motors and the results are positive, most of them have either a gen set or a fuel cell as back up. The fuel cell is more efficient but currently very expensive. Some fuel cells have been developed to use propane/butane, tho not ideal the fuel, is readily available.
In a sail boat with the ability to charge from wind, drag and solar and with the reliability of the electric motor its only a matter of time before the iron main will be purring like a ***** cat.
Opps,seems I have offended big brother with that annology


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## P35juniper

Mgunning, Be carefull keeping those Lifeline AMGs happy, What do you have for a dockside charger? any thoughts on a 48vdc genny? I take it you are planning to have the house bank as a back-up. Keep us updated on good, bad, and different, mustly the different.


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## europaflyer

Sorry for bumping this old thread, but it seemed a shame to start a new one on the same topic!

I'm looking at installing an electric motor on a 32ft 9,500lb yacht which currently has a (horrible) 18hp diesel. I've read through all the pages on this thread, and there are clearly lots of electric powered yacht owners for whom it works really well. It's also been said several times that 'the maths might not add up, but electric motors work in the real world'. I'm currently in that situation. Let me explain!! (and sorry in advance for a big lump of numbers).

Most of my sailing is coastal cruising. This would involve perhaps 1/2 hour of motoring per day (15min in/out of harbour) at 3-4ish knots. Sails up ASAP, I hate motoring! I reckon the boat would need a 10kW motor, and it would probably use 5kW to reach these speeds. Electric Yacht produce a motor which would do the job. Clearly, there is no problem at all in getting this range (and a lot more) from a sensibly sized battery bank. The problem comes in recharging the batteries. I don't really like being a sardine in a marina (who would choose one over a secluded anchorage or a quaint harbour?), I'm on a swinging mooring, and enjoy being self sufficient. Shore power every night is therefore just not a guarantee when out cruising. Using the motor at 5kW for 1/2 hour every day means, then, that I will need to generate, on average, around 100 watts to recharge the batteries (5000 watts divided by 48 half hours in a day = 104). I prefer not to work in amps, it gets confusing! At 15kt, the average wind generator produces 50 watts. The problem is... most harbours or anchorages don't have 15kt of wind, or even close. The wind generator will only really work out on the water, 8 hours per day... in other words average 17 watts. 6 wind generators is clearly not an option! Solar panels... at best, 8 hours of sun per day, and from memory solar panels normally put out about half their rated capacity. To average 100 watts, then, I would need 600 watts worth of solar panels. Not an option either! The same goes for towed generators, 100 watts output but only for eight hours per day. 

If I have a realistic 1 wind generator (50w for 8hr), 1 towed generator (100w for 8hr) and 200 watts of solar panels (100w for 8hr), I would average 83 watts output in a normal day. This doesn't even make up for the power use by the motor, let alone normal domestic consumption (and no, I don't have a TV or anything silly!). Basically, with a fairly impressive array of generating stuff, the battery charge would have dropped to risky levels after a few days, especially when relying on it for propulsion - and I would have to find shore power.

Will any electric yacht owners either back up or dispute my maths? It would be great if it could work, but suspect that electric motors are best either for marina-hopping, or for people that spend days at sea and therefore have plenty of time to recharge batteries - not the average sailor who goes coastal cruising and often finds themselves without shore power. But I would love to be proved wrong! Maybe regeneration with the motor when sailing fills the gap? Maybe I underestimate wind/solar? Overestimate the power needed to push the yacht? Look forward to your replies!!


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## timtim

Cool, I know this is from a older post, but I'm looking to pull the old OMC Saildrive from my S2 8.0B and want to go with electric power. What in your opinion is the best option and company to go with.


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## mgunning

At this time I am not aware of a vendor with a off the shelf saildrive system. We have done several saildrive systems as custom installations. Contact me through my website and I will share information with you and give you some leads where you may follow up.
Regards, Mike
Electric Yachts of Southern California


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