Electric generator/charger?

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Thanks for all of this information and for such a good discussion!

I wanted to address some of the questions, just for clarification.

FYI, the motor I'm installing is the Elco EP-1200 (12 h.p., up to 7 hours range, 33 nm, 106 amps) - and I already mentioned I'm installing 6 batteries, which Elco and my yard agree will give me ample range and power. (My boat's 27' and this motor has specs to 35'). For more info, check out Elco's website (search "Elco electric motor" and you'll get their site & technical specs).

That said, solar panels are NOT recommended because it won't be able to charge sufficiently if I do get into trouble.

My yard is recommending going with the gas generator, and I think I'll take that advice for now. I like the idea of an electric generator, but I think after reading everyone's comments here, the gas generator would be the most reliable.

Regarding adding more batteries, it's being discussed. My funds are tight with the conversion, so if I go with more batteries, it will have to be done later. My fuel tank would need to be removed to accomodate the extra batteries, and that's a big cost...

A large part of this will be trial and error. I will have a panel that will keep me informed of my range, but I was really just concerned about choppy seas and getting stuck in the middle of the Chesapeake Bay without a marina around. The good news is that I am a small picnic boat and will mostly hug the shoreline, so I don't expect to run into problems -- but we all know that things happen out there, so the gas generator is probably the best back-up.

Next season, I'll be able to test the performance of this motor. That's the real issue -- no one knows, but next summer, I suspect I'll know what there is to know about the conversion and can then adjust my power needs after I've gained the experience.

Meanwhile, thanks for this discussion! I learned a lot and just by reading everyone's comments and concerns, it seems like the gas generator is the best choice. Next season, though, I should be an expert on this... :socool:
 
Thanks for all of this information and for such a good discussion!

I wanted to address some of the questions, just for clarification.

FYI, the motor I'm installing is the Elco EP-1200 (12 h.p., up to 7 hours range, 33 nm, 106 amps) - and I already mentioned I'm installing 6 batteries, which Elco and my yard agree will give me ample range and power. (My boat's 27' and this motor has specs to 35'). For more info, check out Elco's website (search "Elco electric motor" and you'll get their site & technical specs).

That said, solar panels are NOT recommended because it won't be able to charge sufficiently if I do get into trouble.

My yard is recommending going with the gas generator, and I think I'll take that advice for now. I like the idea of an electric generator, but I think after reading everyone's comments here, the gas generator would be the most reliable.

Regarding adding more batteries, it's being discussed. My funds are tight with the conversion, so if I go with more batteries, it will have to be done later. My fuel tank would need to be removed to accomodate the extra batteries, and that's a big cost...

A large part of this will be trial and error. I will have a panel that will keep me informed of my range, but I was really just concerned about choppy seas and getting stuck in the middle of the Chesapeake Bay without a marina around. The good news is that I am a small picnic boat and will mostly hug the shoreline, so I don't expect to run into problems -- but we all know that things happen out there, so the gas generator is probably the best back-up.

Next season, I'll be able to test the performance of this motor. That's the real issue -- no one knows, but next summer, I suspect I'll know what there is to know about the conversion and can then adjust my power needs after I've gained the experience.

Meanwhile, thanks for this discussion! I learned a lot and just by reading everyone's comments and concerns, it seems like the gas generator is the best choice. Next season, though, I should be an expert on this... :socool:
l would also make sure I was a member of Sea Tow or BoatUS......
 
Certainly interested in how you project works out. Given what your intended use is, who knows it may be the perfect fit. I looked very seriously into this when I owned a 40 foot sailboat. It would work for that because under sail you were regenerating to charge the batteries. DC Gen to run the house with a large inverter. The gen would run the engine without pulling from the batteries if you needed to do that. Numerous examples of this working on sailboats. Since you can't use the regeneration in the MY it may be more of a challenge. Please keep us informed on how it goes.
 
Even though it may be ugly, maybe a simple backup outboard? A 10hp is still somewhat managable by yourself. A small above deck fuel tank and a transom mount to drop it in the water when you need it.
 

l would also make sure I was a member of Sea Tow or BoatUS......

Yes, so they can bring you a couple jugs of electricity when you run out. :rolleyes:

Seriously, I would recommend a towing membership for anyone boating on anything bigger than a farm pond. Regardless of the means of propulsion.
 
Starside:

Your latest post has me really confused. In my earlier post I deduced from your first post that you have a 4,500 watt motor (375 amps at 12V) which is about 6 theoretical horsepower which seems about right to push a small boat around the harbor.

Your latest post says that you have a 12 hp motor that pulls 106 amps.

May I make a suggestion. Before you finish your design, beg or borrow a similar size boat with a small outboard on it, about 3 hp. See how fast the outboard pushes your boat at wide open throttle. If that works then use 3 hp for your design or more or less depending how the boat drives.

You can still use your 12 hp motor if that is what you have, but you need a control system to limit it to 3 or whatever hp works. Then figure that the motor is about 75% efficient and figure the amperage draw and therefore the battery capacity you need to cruise for 4 hours. You may be surprised.

BTW this is a straightforward electrical engineering exercise. If the boatyard guys advising you do not have that kind of knowledge, find someone who does.

David

David
 
Hi DJ, the Elco EP-1200 is what was recommended for my boat by Elco & my yard, so I have to assume it's the right engine. They assure me I'll have ample range at 6-7 knots for 4 hours.

I'm not an electrician so I don't know the tech stuff, but this project has a lot of yard crew on hand, including electricians, engineers, carpenters etc.

As the owner & a lay person, it could be Im not relaying the info correctly but Elco has a good website if you want to review the specs. I personally am trusting the experts. Elco has done these conversions before, so I'm following their lead. My yard is also a fine crew & I trust their advice.
 
Skinny, an outboard is a good idea but it may not work cosmetically. One reason I got an antique is for her beauty but they do make small electric engines that are sleek - just not sure re powerful enough but it gives me more options.
 
I don't think there is anything wrong with your setup...

You just either need more batteries for farther range or a way of producing electricity at a fairly high rate which in today's world would mean a fossil fueled or propane or alcohol or some other combustible fuel generator.

Some electric guys switched to lithium ion batteries for more power for the size/weight carried. I think a poster named DeckOfficer has toyed with a lot of these and there's an all electric Cat power cruiser that has posted a lot on electric power...they would be some good resources if you are willing to go a bit exotic. A search of electric propulsion and some near decriptors may give you a thread to unravel.

There may be something else but I have seen a few electric launches underway and talked to their owners and read a few articles describing your dilemma. They all basically added batteries or a little genset.

Many boats at some point wish they had more range...there are just limitations that are often difficult to work around though.

Good luck!
 
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I have contacted an owner of a 1909 woodie called Vagabond that he converted using an Elco motor. I have asked him how the conversion went & for his advice. There was a big article on his conversion in the WB Magazine about 2 years ago. He may be a good contact since he's been living with the conversion for a long time now. His boat is 40' I think, so I hope he responds to my reaching out. It would be interesting to see what he says about all this...
 
My yard is also a fine crew & I trust their advice.

Yep, agree. Good place, well-regarded, decades of experience, etc.



I don't think there is anything wrong with your setup...

You just either need more batteries for farther range or a way of producing electricity at a fairly high rate which in today's world would mean a fossil fueled or propane or alcohol or some other combustible fuel generator.

Some electric guys switched to lithium ion batteries for more power for the size/weight carried. I think a poster named DeckOfficer has toyed with a lot of these and there's an all electric Cat power cruiser that has posted a lot on electric power...they would be some good resources if you are willing to go a bit exotic. A search of electric propulsion and some near decriptors may give you a thread to unravel.

There may be something else but I have seen a few electric launches underway and talked to their owners and read a few articles describing your dilemma. They all basically added batteries or a little genset.

Many boats at some point wish they had more range...there are just limitations that are often difficult to work around though.

Good luck!


I tend to agree, and agree, and agree. The set-up is sound, and if it doesn't have all the range in the free world... well, it is what it is (or at least it can be as extensible as it can be made).

An off-the-wall idea about extending range here in the upper Chesapeake... might be a trailer.

Maybe not so elegant as a pleasant boat ride from the West River to the Miles River and then exploring from there... but OTOH, it'd be reasonably quick to just drive the boat over to the general vicinity, launch somewhere useful, and explore the Miles, Wye, and Chester river systems that way.

That approach is also not without it's own issues, though...

-Chris
 
Skinny, an outboard is a good idea but it may not work cosmetically. One reason I got an antique is for her beauty but they do make small electric engines that are sleek - just not sure re powerful enough but it gives me more options.

I know, that is why I hated to suggest it. You could always just spray paint it red and put a big flag on it that says "backup power, do not judge vessel in current condition".

Would a small sailboat inboard engine do the trick? It may take a little engineering to integrate both propulsion systems into one prop shaft. I'm just trying to think inexpensive out of the box here.
 
I'm not an electrician so I don't know the tech stuff, but this project has a lot of yard crew on hand, including electricians, engineers, carpenters etc.

My yard is also a fine crew & I trust their advice.

So why are you asking for advice on this forum? You are a lay person, I understand that. But I promise you that there are very, very few boat yards that know anything about electric boat propulsion much less having the technical skills to design such a system.

I looked at the ELCO site. Here are some problems with your design, none that are insurmountable but indicative of poor advice from your yard or lack of understanding yourself"

The ELCO motor that you have chosen uses 48 V at 106 amps DC maximum. But the motor itself is alternating current, not DC. You will need some kind of inverter/controller to make AC from the DC battery supply. The ELCO site says that you use four 12V batteries to power the motor. That means that you cannot use 6, 12V batteries which gives you 72 volts. You have to use them in groups of 4 for 48 volts.

I presume that ELCO makes an inverter/controller but I can't find anything about it on their site. Maybe that is part of their motor offering, but it is well disguised on their site.

The motor draws 106*48 = 5,088 watts DC at maximum output. That is roughly 5 hp at 85% efficiency (high but that is what ELCO claims). That is roughly what it will take to push a 24', 3,000 lb boat to its hull speed of about 6.5 kts.

But you don't need to go that fast. The electric boats I have been on- Duffys, cruised nicely at 4-5 kts. That will take about half of the wattage and your batteries will last twice as long .

I don't think that you can design this system on this forum. Ask some questions, get some ideas and then go back to your experts.

David
 
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In a recent PassageMaker magazine there was an article where Nigel Calder and Steve D'Antonio argued the merits of electric or diesel electric propulsion on boats. I didn't read it seriously because I don't really care but the whole think was inconclusive at best.

Now these are a couple of the best minds in the marine industry. If they can't come up with a practical electric powered boat or find someone who has, I can't imagine an inexperienced boat owner doing it.

I'm still looking for what was meant by the term "electric generator" but it looks like I'm not going to get my answer.
 
Thoughts on "electric generator". A battery powered DC motor driven A.C. generator maybe ? We used a similar device on service trucks in the late 80s. It was a dc motor driving a small gen. This was befor inverters became popular. Good for running power tools.
 
C'mon guys. The OP obviously misspoke or was misinformed when he asked about an "electric generator/charger". The only usable device for his purpose is more battery capacity or a separate generator.

Has anyone on this thread ever used an electric boat? I have and they are delightful for a short, 1-2 hour harbor cruise. We lived in Newport Beach a few years ago and it seemed like every third waterfront home (not ours I can assure you!!!) had a 21' Duffy at their dock. They would use them for an early evening cocktail cruise around Newport Harbor or to get to one of the waterfront restaurants there.

I rented one once for a cocktail cruise for a couple of hours. There was a rental fleet of a half dozen or so off of the PCH. Very quiet and very nice. You wouldn't think about taking one anywhere beyond the harbor. But for that mission, it was perfect.

David
 
The elco motor appears to be a ac induction motor, inverter and vfd all in one enclosure. Not the hefty gauge black and red wires going into the finned aluminum housing assembly.

Bet it gets warm...
 
Well, if it has an alternating current motor and a battery bank to run it there has to be something in between. A DC driven AC generator would do it. I am not familiar enough with electric propulsion to even guess how the variable speed controll would operate.
 
Please - What do you mean when you speak of an "electric generator"?

X2. I think this is where the confusion lies. Can you post a link to what you think you want or something similar?
 
Perhaps but why won't he answer our questions or explain?

Not avoiding you...just at work...

Re the portable "electric generator," I was asking if there was such a thing. I know there are portable gas and diesel generators, but I was just curious - and if you look through the beginning of the thread, you'll see that that was already discussed and that an "electric generator" was dismissed as something that doesn't exist or just wouldn't work...

The goal was to charge the batteries in case of an emergency - Example: you are 30 minutes away from your destination and you notice you are running out of juice. What do you do? Well, here were the fine suggestions from this thread: you either need a portable generator to charge your batteries so you can get back to dock, OR perhaps back-up batteries, OR an outboard could also get you home... Someone also suggested a towing membership. :D

Anyway, someone mentioned above that I should not ask for advice here, and sorry about that. I was honestly just curious and contemplating my options. Still, you are right -- I have a boat yard who is doing the work and they recommend a portable gas generator. So, problem solved.

I was just curious if other options were out there, and more so, if others had experience with their electric boats and increasing their range...didn't mean to cause any trouble... :facepalm:
 
If I were undertaking your project, I probably would have considered a Steyr Hybrid engine but I suspect the price tag is a budget breaker compared to the Elco. Here is a link to a 40' Island Pilot powered by twin Steyr 75HP hybrids with lots of solar panels and a 50Kw/hour lithium battery. This boat is about as green as it gets and claims a 25NM range on a charge.

2009 Island Pilot DSe12m Hybrid Power Boat For Sale - www.yachtworld.com

Steyr has smaller engines but the smallest is 26HP which is probably aimed at the sailboat market but they are also used for generators.

A portable Honda gas generator is probably your best approach now to get you going and it is a fairly cheap solution. Once you gain more experience with your boat and its limitations, you will probably want solar panels or a wind generator to provide a charge while underway or while on the hook if you ever decide to anchor.

Good luck with your project.
 
Not avoiding you...just at work...

Re the portable "electric generator," I was asking if there was such a thing. I know there are portable gas and diesel generators, but I was just curious - and if you look through the beginning of the thread, you'll see that that was already discussed and that an "electric generator" was dismissed as something that doesn't exist or just wouldn't work...

A generator powered by an electric motor receiving power from the same source that it's trying to recharge would be a "perpetual motion machine" if it worked. The reality is that the power it put out would be considerably more than the power it consumed. I gave an example of an "electric generator" from many yr=ears ago and another member provided another example. Both of these were for special purposes where the loss of efficiency was secondary to the need for the generator.

I think the comment about not asking for advice here was based on the fact that you stated that you had experts doing your project already. These folks will not take kindly to you suggesting that they do something differently based on something you read on a web forum. In other words, trust them to do the work or find someone else you trust more.

Now as far as a Honda generator, unless it's a very large one, you will be using power from your batteries faster than the generator can provide it so you'll have to start it up well before the batteries get low. How about a diesel genset?
 
I'm sorry but I have to chime in here...how much power are you getting from a portable genset? Most that can be carried on a dinghy or down a pier is going to be 2000 watts. Maybe a 2500-3000 watt if you are feeling strong. No one is carrying a fully framed 5000 watt genset by themselves off the back of a truck, down a dock, then into the back of a vessel. Maybe with two guys but that defeats the portability. Not to mention something that size takes up considerable space in the boat.

For conversation sake, we will call it 2000 watts max portable gas power. So you dump $1000 for a nice EU2000i genset. You still have to get it running on the boat, wire to a charger, burn fuel, hear it run, etc.

Why not just buy using that same amount of money solar panels. They will charge continuously while motoring for free, nice and quiet, and worse case you have to stop motoring to charge up. No transporting gensets, fuel, etc.

No portable genset is going to give you enough power to cruise home with dead batteries, period. So why not just eliminate it all together?

Just my two cents...don't give up though, cool stuff is built by people that step outside the box.
 
.......... a wind generator to provide a charge while underway ............

Now there's an idea. A wind generator on a boat to charge a battery to keep an electric boat going. Anybody see anything wrong with that idea?
 
Now there's an idea. A wind generator on a boat to charge a battery to keep an electric boat going. Anybody see anything wrong with that idea?

Pray, tell us more about your thinking. I do suspect wind power would be better at anchor and really meant to pitch solar panels but wind should make good augmentation. One of posters, I believe Mule, has both solar and wind.
 
Not avoiding you...just at work...

Re the portable "electric generator," I was asking if there was such a thing. I know there are portable gas and diesel generators, but I was just curious - and if you look through the beginning of the thread, you'll see that that was already discussed and that an "electric generator" was dismissed as something that doesn't exist or just wouldn't work...

The goal was to charge the batteries in case of an emergency - Example: you are 30 minutes away from your destination and you notice you are running out of juice. What do you do? Well, here were the fine suggestions from this thread: you either need a portable generator to charge your batteries so you can get back to dock, OR perhaps back-up batteries, OR an outboard could also get you home... Someone also suggested a towing membership. :D

Anyway, someone mentioned above that I should not ask for advice here, and sorry about that. I was honestly just curious and contemplating my options. Still, you are right -- I have a boat yard who is doing the work and they recommend a portable gas generator. So, problem solved.

I was just curious if other options were out there, and more so, if others had experience with their electric boats and increasing their range...didn't mean to cause any trouble... :facepalm:

Starside- There are engineers and other technical folks on this site, and when you enquired about the "electric generator", it rather stunned us. As you described it, it would be a "perpetual motion machine" that violates the laws of physics. Or it would be the equivalent of a "jump pack" used to start a car, and that does not contain enough energy to matter in your case. Stuff most learned in 8th grade science class.

You are undertaking a project where many decisions need to be made in the realm of both electrical, mechanical and naval engineeering. Experts in these fields have built similar boats with less than desired results. Designing adequate energy storage, charging systems, range extension and propulsive power must all be integrated, and there will be tradeoffs. You simply cannot do with current batt technology what a simple diesel can do.

While you have delegated the system design to a yard you trust, as the owner you need to get up to speed on some basic electrical engineering in order to avoid design mistakes. Or get the help of engineers or other highly experienced techies to guide you.

That's a classic boat, just don't want to see it screwed up.

Once you get all the propulsion system bits selected, post them here and we'll give it a review.
 

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