The electronic alternative to emergency Engine

North Baltic sea · Jan 5, 2017

if this is known here, Ocena volt electric motor and a desire to recharge your batteries?

some single engine is a small emergency diese home to help if someone fails in the engine. Ocean volt is developed sailboats electric motor propulsion that could be used as a motorboat. needs a generator, batteries or solar panel system. thought the might be good, do not need annual maintenance, such as diesel, zinc replacement might be.

http://oceanvolt.com/systems/sea-for-monohulls-multihulls

This video 40" sail boats

https://youtu.be/9XTM6PAGi_Q

O C Diver · Jan 5, 2017

Looks like a nice get home drive for a sub 40' boat that could be tied to your generator. Wonder how long a duty cycle it has in that kind of application.

Ted

North Baltic sea · Jan 5, 2017

O C Diver said:
Looks like a nice get home drive for a sub 40' boat that could be tied to your generator. Wonder how long a duty cycle it has in that kind of application.

Ted

I can not say more sustainability, as electric motors and saildrive is both old inventions and proven to be reliable. if these reliable individual components combine to think of this type of propulsion motor + to be good.

Also I think that this could be to involve more quickly than the wing of diesel in case of need and, above all, less technical maintenance (oil, filers, winter protection, etc.

Unfortunately, priced about the same as the diesel + Advanced transmissions wing.

twistedtree · Jan 7, 2017

One challenge running any form of propulsion, whether hydraulic, electric, or other, from a generator is the general discrepancy in power requirements. The power required to generate electricity for a boat is typically much less than the power required for propulsion, even auxiliary propulsion.

For example, my boat has a 20kw generator which is arguably oversized for the boat. The engine that drives the generator is about 35hp, so if it were used as auxiliary propulsion, I would have as most a 35 hp drive engine. In contrast, my wing engine is 80hp, so over 2x the power, and even at that it only drives the boat at about 5 kts.

Now it can certainly be done, and I know a couple of people who have generator-driven get home drives that work acceptably, but you have to pay careful attention to get good results.

ranger58sb · Jan 7, 2017

twistedtree said:
For example, my boat has a 20kw generator which is arguably oversized for the boat. The engine that drives the generator is about 35hp, so if it were used as auxiliary propulsion, I would have as most a 35 hp drive engine. In contrast, my wing engine is 80hp, so over 2x the power, and even at that it only drives the boat at about 5 kts.

Now it can certainly be done, and I know a couple of people who have generator-driven get home drives that work acceptably, but you have to pay careful attention to get good results.

Given a large enough boat to take advantage of it...

I've often wondered if it'd be feasible to have two gensets on board, alternated (daily?) for normal house loads... and combined for get-home, or at least steerage way, loads.

-Chris

sunchaser · Jan 7, 2017

If one desires, twin engines. Or the get home JD 4045 on the FPB 64 will drive the vessel at 8 knots. Ranger Tug's have a neat swim platform designed outboard arrangement.

As Baltic points out the sail drive arrangement is practical, as also exemplified by Z drives on ocean going tugs.

twistedtree · Jan 7, 2017

ranger42c said:
Given a large enough boat to take advantage of it...

I've often wondered if it'd be feasible to have two gensets on board, alternated (daily?) for normal house loads... and combined for get-home, or at least steerage way, loads.

-Chris

That's exactly what one of the boat's I mentioned does. But it's 75' or so with two 20 or 25kw gensets.

North Baltic sea · Jan 8, 2017

Hi,

I found secod mark electric inboard engine 40 or 80 hp made torpedo. Trondheim electric (i think hybrid) trawler have 2 pices torpedo engines.

These take up less space than a diesel engine wing, could not be easier to install the old boats.

Electric outboards by Torqeedo

twistedtree · Jan 8, 2017

Every time I look at our Deere 4045 wing engine, sitting idle, with a whopping 20hrs on it, I think there must be a better way. It seems like such a waste of a great engine, and is what brings many people to hydraulic drives powered from generators as their get-home propulsion.

But the down side of a hydraulic drive is that it uses the main engine running gear, so if your running gear has become fouled, it's of no help. That's one of the arguments for a wing engine with it's own running gear.

An alternative that has caught my attention is to keep the wing engine shaft and folding prop so you preserver redundant running gear, but replace the gear and engine with an electric or hydraulic drive motor. Then power it off dual generators. On larger boats, lots of people have dual generators, both for redundancy, and often with different power ratings for high-peak and low-peak operation.

A second generator strikes me as much more useful than the wing engine/gear, provided I have some alternate way to drive the wing prop. It does still bring up the issue of total power requirements. Two 20kw generators is about 70hp replacing an 80hp wing engine. And you need to hold back some of that power for electric generation to run the boat. I don't know how much efficiency loss there is with hydraulics, but I doubt it's better than 20%, so it's probably closer to 50hp actually available to drive the boat when all is done.

cafesport · Jan 8, 2017

Peter our boat needs about 80 hp to run at the sq root of our waterline. So taking a 40 hp saildrive unit I look at it like this.

40hp is the energy required to run 20 of my wife's hairdryers. We're a 24 volt boat so that's 1250 amps/hour. After a half hour run we'd only be a mile and a half 2 tops, from where we turned the bloody thing on. Then it would take the rest of the day to recharge our fully depleted battery bank. No thanks, I can get to the same place in half the time using 80 percent less fuel just running on one of our diesel engines. There still will be enough battery power for my wife to use her hair dryer at night and more importantly start the engine again in the morning.

D.C. motors for marine propulsion are great, but you really need lots of stored available energy and that means battery power as opposed to diesel fuel. Think nuclear power like the Russians do on the Arktika class ice breakers and you can have it all. Well not quite, keeping the reactors cool kinda limits your cruising areas.

sunchaser · Jan 8, 2017

twistedtree said:
Every time I look at our Deere 4045 wing engine, sitting idle, with a whopping 20hrs on it, I think there must be a better way.

Peter, I went through the same questions and analysis a few years ago when looking at new builds. Assuming one wants get home power sufficient to move the vessel in a strong seaway, electric or hydraulic driven props came out to be a higher cost, more complicated and greater space arrangement than a small diesel wing engine.

While looking at new builds, I also looked at a 52 FD vessel that was lightly used but had no get home setup. I queried the well known builder as to the cost for an approximate 60 HP get home. The all in cost to factory install including hull penetrations and drive line was about $35K.

Another data point for your hull is the cost differential between single/get home vs twins with dual keels. On the 55s Nordhavn said about the same cost but with a fuel penalty of ??. I believe about a half a dozen were built.

So IMHO , you have the most cost effective setup for your vessel smart minds could devise. BTW, what hydraulic drive setup did Star finally end up with, if any. That is another data point.

ranger58sb · Jan 8, 2017

twistedtree said:
That's exactly what one of the boat's I mentioned does. But it's 75' or so with two 20 or 25kw gensets.

Useful to know.

twistedtree said:
Every time I look at our Deere 4045 wing engine, sitting idle, with a whopping 20hrs on it, I think there must be a better way. It seems like such a waste of a great engine, and is what brings many people to hydraulic drives powered from generators as their get-home propulsion.

An alternative that has caught my attention is to keep the wing engine shaft and folding prop so you preserver redundant running gear, but replace the gear and engine with an electric or hydraulic drive motor. Then power it off dual generators. On larger boats, lots of people have dual generators, both for redundancy, and often with different power ratings for high-peak and low-peak operation.

A second generator strikes me as much more useful than the wing engine/gear, provided I have some alternate way to drive the wing prop.

sunchaser said:
Peter, I went through the same questions and analysis a few years ago when looking at new builds. Assuming one wants get home power sufficient to move the vessel in a strong seaway, electric or hydraulic driven props came out to be a higher cost, more complicated and greater space arrangement than a small diesel wing engine.

Maybe turn thinking backwards on itself. If two gensets and an electric (pod?) drive isn't cost-effective... (Wouldn't have guessed that more complicated or requiring more space than a dieselwing/gear/shaft, but anyway...)

Instead of letting a perfectly good diesel wing engine sit idle, maybe it'd be a good second generator -- or instead, a higher load generator compared to a smaller one main generator. Run that engine every other day or whatever to power a generator...

??

-Chris

sunchaser · Jan 8, 2017

ranger42c said:
Maybe turn thinking backwards on itself. If two gensets and an electric (pod?) drive isn't cost-effective... (Wouldn't have guessed that more complicated or requiring more space than a dieselwing/gear/shaft, but anyway...)

Instead of letting a perfectly good diesel wing engine sit idle, maybe it'd be a good second generator -- or instead, a higher load generator compared to a smaller one main generator. Run that engine every other day or whatever to power a generator...

??

-Chris

Or, and commonly done - setup the wing engine as an auxiliary primary hydraulic driver. With PTOs attached it can run thrusters, 0 speed stabilizers, lifting devices and anchor thus allowing main engine to idle you into slip or where ever. The vessels I've seen with this setup have many more than a few hours per year on the wing engine.

Or power a hydraulic motor as an auxiliary on the main shaft and skip the spare shaft and transmission. A JD 4045 like 55/60 Nordhavn's have as a wing engine would have about a 50 -60KW genset. That generator is larger than a v drive - maybe.

Lots of alternatives but at what cost and complexity is the question.

twistedtree · Jan 8, 2017

I'm pretty sure Starr ended up with an ABT hydraulic drive.

All these trade-offs are a big part of the fun in boats, and the curse.

Yes, it's quite common to use the wing engine to power aux hydraulics, and most nordhavns are built that way. We included ABTs stabilization at rest in our build, and with that it made more sense to power the aux hydraulics off the generator. The down side of course is less use of the wing engine.

North Baltic sea · Jan 9, 2017

cafesport said:
Peter our boat needs about 80 hp to run at the sq route of our waterline. So taking a 40 hp saildrive unit I look at it like this.

40hp is the energy required to run 20 of my wife's hairdryers. We're a 24 volt boat so that's 1250 amps/hour. After a half hour run we'd only be a mile and a half 2 tops, from where we turned the bloody thing on. Then it would take the rest of the day to recharge our fully depleted battery bank. No thanks, I can get to the same place in half the time using 80 percent less fuel just running on one of our diesel engines. There still will be enough battery power for my wife to use her hair dryer at night and more importantly start the engine again in the morning.

D.C. motors for marine propulsion are great, but you really need lots of stored available energy and that means battery power as opposed to diesel fuel. Think nuclear power like the Russians do on the Arktika class ice breakers and you can have it all. Well not quite, keeping the reactors cool kinda limits your cruising areas.

I do not know what size boat you have, so electric is not necessarily suitable for you and your batteries run does not really make sense. Mine is NT37 and I 4,5kw generator and motor Oceanvolt 40 'footer boat needs up to 4kw achieve 7 knots (start the video chain) I have a generator is quite unnecessary in the boat, so there could be meaningful to use. Buying diesel wing engine should be serviced while one

Ski in NC · Jan 9, 2017

I could see a get-home electric driven pod make sense on some boats. Instead of 12 or 24v, wind it for 120 or 240Vdc, then it can be run through a simple rectifier with relatively light gauge cabling.

With a normal sized gennie, say 8kW on a 42', you have enough power for 10hp of propulsion. That's enough to move the boat at half hull speed. Can you make way against a heavy head wind or head sea? No. But you will be able to make way in some other direction. That should be sufficient to get the boat safely... somewhere.

ranger58sb · Jan 10, 2017

Ski in NC said:
I could see a get-home electric driven pod make sense on some boats. Instead of 12 or 24v, wind it for 120 or 240Vdc, then it can be run through a simple rectifier with relatively light gauge cabling.

Not AC??

Is there such a thing as an AC pod drive? What voltage/current do the big ships' electric pods use?

(I haven't even yet found what voltage that OceanVolt unit, linked above, uses...)

-Chris

Ski in NC · Jan 10, 2017

ranger42c said:
Not AC??

Is there such a thing as an AC pod drive? What voltage/current do the big ships' electric pods use?

(I haven't even yet found what voltage that OceanVolt unit, linked above, uses...)

-Chris

You could go AC, but would either need a controller or it would have massive start amps. DC motor I think is what would be easiest.

I think motor tech now favors AC using a controller to shape waveform, but at 10hp that is a pretty expensive. DC might be easier.

Regarding the volts, most motors are presently lower volts as they are designed to run on batt banks. To run directly off the gen output it probably would be easier to set up motor for higher volts. Thinking less processing would be needed.

Not sure what would be best. That's for motor engineers to figure out.

rochepoint · Jan 10, 2017

ranger42c said:
Not AC??

Is there such a thing as an AC pod drive? What voltage/current do the big ships' electric pods use?

(I haven't even yet found what voltage that OceanVolt unit, linked above, uses...)

-Chris

Specs say they operate on 48 volts......

ranger58sb · Jan 10, 2017

Ah, thanks Mike. I apparently never found that page. Did see lots of refs to battery banks and so forth; 48V, must be DC then...

-Chris

ranger58sb · Jan 10, 2017

Ski in NC said:
You could go AC, but would either need a controller or it would have massive start amps. DC motor I think is what would be easiest.

I think motor tech now favors AC using a controller to shape waveform, but at 10hp that is a pretty expensive. DC might be easier.

Regarding the volts, most motors are presently lower volts as they are designed to run on batt banks. To run directly off the gen output it probably would be easier to set up motor for higher volts. Thinking less processing would be needed.

Not sure what would be best. That's for motor engineers to figure out.

I think I've seen AC thrusters refed in some on-line reading? Said to be a good thing?

Our 8 kW genset can run two chargers (40A and 70A) plus two 1600 BTU ACs, water heater, plus cooktop, microwave, etc. -- start-up loads semi-simultaneously, as far as I know -- all at once. Boatload of amps; maybe if all (or most of) that current was channeled into a pod drive instead, it'd be more better (the scientific term, I bet) than a 48V DC pod drive? At least for get-home or emergency steerageway?

Just speculating, without many actual factoids on hand...

-Chris

twistedtree · Jan 10, 2017

I'm far from an expert, but my understanding is that most large variable speed electric motors are AC, controlled by variable frequency drives. They are essentially inverters where you can control the frequency and voltage to control the speed of an AC motor. Large thrusters, propulsion motors, trains, and electric cars all work this way, as I understand.

Offshore 54 · Jan 20, 2017

Electric seems right?

Hello everyone, first post. I have looked at a few options for a get-home system with limited space. So far, an electric (48/72 VDC) driven saildrive seems the best option (but lots of research to do yet). The Oceanvolt unit seems the best do far - simple and enough to push me along at a knot or two. It is not really designed as a get-home, more as power for a sail boat (large battery bank, etc.) What I need is a drive system that will operate off the genset and provide limited forward progress. If anyone has ever installed an Oceanvolt system (or other) in a displacement boat as an aux drive I would really like to hear about it.

North Baltic sea · Jan 21, 2017

Selene48 said:
Hello everyone, first post. I have looked at a few options for a get-home system with limited space. So far, an electric (48/72 VDC) driven saildrive seems the best option (but lots of research to do yet). The Oceanvolt unit seems the best do far - simple and enough to push me along at a knot or two. It is not really designed as a get-home, more as power for a sail boat (large battery bank, etc.) What I need is a drive system that will operate off the genset and provide limited forward progress. If anyone has ever installed an Oceanvolt system (or other) in a displacement boat as an aux drive I would really like to hear about it.

would certainly be a coincidence that here in the TF would be someone with first-hand experience oceanvolt. You can look at their references 14 pages of their web link below. I believe that you can ask the user experience them. there are charter companies and yksityisijä cause the users to be found in the website, FB, twiter, etc. I think you'll want to be contacted by e-mail oceanvolt and chat about your case, you can also ask for references from whom to ask

Oceanvolt blog - Customer stories & events
top right of the page catecories red text you will find installed on your system

cafesport · Jan 21, 2017

North Baltic, Our boat is one of the afore mentioned twin engined 55's. A sister ship to Peter's with about 6 fewer feet of waterline and 10 less tons of displacement.

I feel the current problem and why an electric drive for our boat's makes no sense is because diesel fuel and even gasoline for that matter are an order of magnitude higher in energy density than the current state of the art lithium battery systems. A single gallon of diesel weighs only 7 pounds but contains over 40kw of energy. Fully fueled, our boat's carry megawatts of energy onboard ready to use. Even considering the efficiency losses in diesel propulsion and adding the efficiency gains from D.C. motors in electric propulsion, we still need more kw of electricity than battery banks can carry. Any efficiency gained via the D.C. motor slowly disappears once you start replenishing it with a diesel generator/shore power.

It's all in the numbers.

1hp is still about 750 watts and yes that means your wife's hair dryer is 2 hp.

Hydraulics, 1 GPM at 1500 psi also equals 1 hp.

1gal of diesel contains about 40,400 watts of energy.

Current state of the art electric propulsion motors might be 3 times more efficient per kw than diesel, but those kw also come out of a battery bank faster than sun wind or even diesel generators can replace them.

For some boat's and owners like Donald Street and Iolaire it might work. Note, Street did take the engine out and sailed her over 200,000 before going back to a diesel electric auxiliary in 2007.

The Russians use nukes and steam turbines powering dynamos outputting 10,000 VDC. to turn the props on their arktika class ice breakers. .2kg of uranium per day when breaking 3 meters of ice gives them 13 years of stored energy to use during their voyages. A kilowatt is still a kilowatt, no matter the source.

Selene48 welcome to the forum, you might try a google search for iolaire or Donald Street for some info. He has had a love hate relationship with auxiliary power his whole life.

Offshore 54 · Jan 21, 2017

twistedtree said:
I'm far from an expert, but my understanding is that most large variable speed electric motors are AC, controlled by variable frequency drives. They are essentially inverters where you can control the frequency and voltage to control the speed of an AC motor. Large thrusters, propulsion motors, trains, and electric cars all work this way, as I understand.

I think you are right, but in all my searching I have not been able to find a variable speed/frequency AC motor in the size I need (say 10 to 15 kW). The only motors I have found are DC driven indirectly by a genset via a battery bank/controller. Some have been adapted to saildrives (Elco) and some are complete units (Oceanvolt). There may be an obvious reason a variable speed drive cannot be connected to the genset (via a controller) but I have not been able to find anyone that can tell me why this wont work. I have also not been able to find anyone that can tell me why a DC saildrive unit could not (or should not) be used as an after-market aux drive system. Guess I'm hoping someone on the forum has already worked through this.

North Baltic sea · Jan 22, 2017

cafesport said:
North Baltic, Our boat is one of the afore mentioned twin engined 55's. A sister ship to Peter's with about 6 fewer feet of waterline and 10 less tons of displacement.

I feel the current problem and why an electric drive for our boat's makes no sense is because diesel fuel and even gasoline for that matter are an order of magnitude higher in energy density than the current state of the art lithium battery systems. A single gallon of diesel weighs only 7 pounds but contains over 40kw of energy. Fully fueled, our boat's carry megawatts of energy onboard ready to use. Even considering the efficiency losses in diesel propulsion and adding the efficiency gains from D.C. motors in electric propulsion, we still need more kw of electricity than battery banks can carry. Any efficiency gained via the D.C. motor slowly disappears once you start replenishing it with a diesel generator/shore power.

It's all in the numbers.

1hp is still about 750 watts and yes that means your wife's hair dryer is 2 hp.

Hydraulics, 1 GPM at 1500 psi also equals 1 hp.

1gal of diesel contains about 40,400 watts of energy.

Current state of the art electric propulsion motors might be 3 times more efficient per kw than diesel, but those kw also come out of a battery bank faster than sun wind or even diesel generators can replace them.

For some boat's and owners like Donald Street and Iolaire it might work. Note, Street did take the engine out and sailed her over 200,000 before going back to a diesel electric auxiliary in 2007.

The Russians use nukes and steam turbines powering dynamos outputting 10,000 VDC. to turn the props on their arktika class ice breakers. .2kg of uranium per day when breaking 3 meters of ice gives them 13 years of stored energy to use during their voyages. A kilowatt is still a kilowatt, no matter the source.

Selene48 welcome to the forum, you might try a google search for iolaire or Donald Street for some info. He has had a love hate relationship with auxiliary power his whole life.

hey, I do not know the issue in depth, and is not intended to Ridella matter that I do not feel better.

I know that the big cruise ships such as the allure of the Seas and Oasis of the Seas, the world's bigest cruisers moving electric motors. 4 big ship Wärtsilä diesel generators rotate only generators. The ship moves three AAB Azipod 20mW electric motor with propellers. fuel savings of 10-15% in a traditional shaft propulsion. If the ships are OK to make electricity from a diesel generator and electric motor to drive, so you would think this concludes the financial smaller scale?

I know these ships quite well because I have been provided by a large Turn Key project for these ships.

http://www.abb.fi/cawp/seitp202/33b33b0b792201d4c12576710035b74f.aspx

Ski in NC · Jan 22, 2017

No doubt that the fundamental engineering for an electric get-home system is well established.

Two issues exist, sort of related: First is whether anything already out there on the market can be readily adapted. Looks like the sailboat pods would be ready to bolt on. It would not be practical to design something from scratch considering the cost of such and the small market.

Second is power. For this to work, batteries will not store enough power without being a huge and expensive bank. It will need to be diesel powered in order get the capability to run days on end. Some batteries may be needed for power conditioning for machine startup, etc, but that can be a small bank.

To size a generator large enough to support the get-home, it may be too large to efficiently power normal ship's load.

If you size the generator for the ship's load, it may only be able to power something like a 5hp thruster. That will certainly move a boat in good conditions, but will not be enough to move it against any decent sea or wind. Is that "good enough"? You might be able to choose a downwind course. Maybe.

ranger58sb · Jan 22, 2017

Ski in NC said:
To size a generator large enough to support the get-home, it may be too large to efficiently power normal ship's load.

Another pointer to considering multiple generators, maybe? Each sized for normal ship's load, normally alternate days on each, bring all on line for emergency get-home? Or at least steerage-way?

Would need a boat large enough to accommodate...

Maybe feathering props on the sailboat pod?

-Chris

Offshore 54 · Jan 24, 2017

Just received a set of photos of a Torquedo electric drive installed in a 52'trawler - in the lazarette. Looks like a nice/simple way to add an aux drive. Very few details yet - but will post when I get them. And if I could just figure out how to paste one of the pictures I would.....

The electronic alternative to emergency Engine

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Guru

Technical Guru

Guru

Technical Guru

Guru

Attachments

Guru

Guru

Guru

Member

Guru

Guru

Member

Guru

Technical Guru

Guru

Member

Similar threads