# Electric Propulsion - solidnav.com



## engele

I have a friend who is involved in a company called Solidnav. They are selling electric sailboat re-power gear. I thought that it would be neat to hear from anyone who had actually done an electric conversion and see how their conversion went? Who did you go with, and how did it work out?

I've looked a bit and I see a lot of DIY type stuff and then the really expensive saildrives, but little in-between. Would any of you who have done an electric conversion try a product like the Solidnav Explorer in a re-power? 

The first one off engine that they made worked well, and it seams that they have solved a lot of issues in the first run that remain on other systems production units. The motors are not brushed motors, the controller is sealed, it is belt driven with a reduction gear, etc.

I guess I am sold on the product, but then I am close to it as well. The Engineers seem to have done a lot right. What do you think?

solidnav.com


----------



## Rockter

Not for me. 

Not enough sun here boys, and none at night.

"Remove your portion from our oil burden while silently cruising into distant harbors".... what????

Beware you don't get swept along with the great global warming cabal.

In blazing heat, through the doldrums, with solar cells everywhere, an 8 kW electric motor will move your ship ok, but from where would you get the energy needed... 8 kW+ ? 

And how fast would solar cells really move a 10 ton ship? It's not the power of the motor that bothers me. they could list 100 hP in there. The vital questions is the energy source, not the power of the motor.

Be sceptical.


----------



## artbyjody

That is a very NEW company. For the last three years I have pretty much been to every "e-power" website - this was not one of them. Re-e-power has been in the business the longest and even they have problems with keeping up, and the changes they have to make. 

The one crucial thing to consider in any endeavor of this type is that they require huge battery capacity. No way any amount of solar unless your hull and deck is made of solar panels - do you get "free energy". The regen capabilities are only a small fraction of the total battery capacity to begin with.

Hence why Soloman, Volvo, and other hybrid sail drive manufactures bundle in generators otherwise you would be limited to 4-6 hours of engine time before needing to spend 12 or more hours recharging. Lets face it - rarely if you are cruising is it always under sail. Here in the PNW I spend more time motoring to get somewhere - unless its a daysail and I don't mind drifting around a bit. 

If all you do is casual day sailing - maybe its all worth it as you are not doing anything extended in lines of point to point traveling. Otherwise - you have to look at the actual nature of what you can accomplish with one of these units. But I would say beware - there are no reviews and the company in question maybe just a fledgling company trying to make a start - but in the end you might want to know that for warranty issues etc they will be around awhile...


----------



## TSOJOURNER

I think that the electric motor will become popular once the price of fuel cells becomes bit more reasonable. The solar option is not really viable in much of the world.

FWIW I intend to install an ASMO set up when my diesel dies (if that is not after I have died  )


----------



## Architeuthis

It looks like they have a good product, nothing new, which is good. 
They are using 48volts which is also good. Almost every boat has room for 4- 12volt batteries. 

I will consider this system closely as I would like an elect drive for various reasons. 

As already mentioned to get any range at all you will need a generator. There are applications where you wouldn't need a diesel gen. These include: Day sailing where motoring out of the harbour only takes a few minutes, offshore sailing where harbours are days away, and for sailors who can adapt to not always having an engine or having to conserve the use of motoring. 

The reason electric drives have not taken off is not technical. They always have been a very viable alternative, even superior in many cases but they have a major problem. 

All the patents needed for electric propulsion have run out. Electric drive systems are so much cheaper that no major company is going to make billions. Even if they "caught on" and started to sell some company in India or China could undercut the market, heck people can just build them in their garage. 

And many do. thousands of people have used electric drive systems. General Motors says they cannot make an electric drive car for less than hundreds of thousands of dollars each but thousands of people have converted cars for less than $20G. 

Most of the negative views and opinions about electric drives are a result of the established industries advertising against a competitor. Objectively electric drive systems are better in most applications and this is true for sailboats which already have a need for large battery installations. 

It is even better for motorsailors because the generator, battery, motor system gives much better fuel economy and the ability to use power other than that derived from diesel. 

The only down side is the high up front cost. People wont insulate their homes to save money later so it is with removing a perfectly good diesel engine and replacing it with a more expensive motor-gen-battery system. 

EDIT: They do have these systems available on about 3 weeks notice, which isn't long to wait considering it is a complete engineered package (sans batteries of course).


----------



## Rockter

There is no way on this earth, with earthly laws of physics, that a fuel-driven electric generator, feeding mechanical energy to a generator, then electrical energy to a motor, and from there mechanical energy to a prop will EVER out-perform the direct drive-to-prop diesel in the first place. There is just no way that can happen.

What am I missing here?

If you want something quiet to get you in and out of harbour, then perhaps, but this stuff must not be advertised as being capable of prolonged motoring into a tide, or headwind, or chop, or all three.

It won't cut it, unless you have a very big battery bank indeed, and a lot of time to charge it.

For example, 25 hp (shaft power at the prop shaft) for 6 hours is about 112 kWh delivered, and probably about 1/4 more than that is needing storing to deliver on it. They will not try to deliver that at 12V, but, if they did I calculate the energy storage to be (corect me if I am wrong)...

112 kWh * 1.25 = 140 kWh = 140,000 Wh = 140,000*3600 = 504 MJ 

.... call it E.

If you are to find E from your battery bank, then...

E = current*voltage*time

E = I*V*t 

Make the product of I*t the subject...

I*t = E/V

Say, for argument, your power is delivered at 12 volt...

I*t = 504,000,000/12 = 42,000,000 amp.second

= 11,666 Ah

My current house battery is 275 Ah.... that is about 1/42 of what would be needed for 6 hours motoring.

That was 6 hours motoring, and I'd need 11,666 Ah to do it, discharging the batteries to nil to do it.

My current tank capacity will keep the motor running for about 30 hour.

Pls correct me on this one there guys. Did I get it wrong?


----------



## artbyjody

Nope Rocket -you summed it up well


----------



## Architeuthis

Rockter said:


> What am I missing here??


A: The efficiency increase in the diesel engine being used to drive the generator.

Many drive systems do not have the diesel engine directly connected to the drive wheels or propeller and most do not use the battery bank. A sailboat would because it has many other uses for a battery bank, including silent drive mode.

And your are missing the fact that it is not a straight conversion of HP to KW when looking at replacing a diesel with an electric drive. The drive in question is using a 4KW system (7.2KW peak, [email protected]) to replace a 24HP system. Again efficiencies of the electric system and the inefficiencies of the diesel system are not being taking into account.


----------



## MedSailor

Rockter said:


> There is no way on this earth, with earthly laws of physics, that a fuel-driven electric generator, feeding mechanical energy to a generator, then electrical energy to a motor, and from there mechanical energy to a prop will EVER out-perform the direct drive-to-prop diesel in the first place. There is just no way that can happen.
> 
> What am I missing here?
> 
> If you want something quiet to get you in and out of harbour, then perhaps, but this stuff must not be advertised as being capable of prolonged motoring into a tide, or headwind, or chop, or all three.
> 
> It won't cut it, unless you have a very big battery bank indeed, and a lot of time to charge it.
> 
> For example, 25 hp (shaft power at the prop shaft) for 6 hours is about 112 kWh delivered, and probably about 1/4 more than that is needing storing to deliver on it. They will not try to deliver that at 12V, but, if they did I calculate the energy storage to be (corect me if I am wrong)...
> 
> 112 kWh * 1.25 = 140 kWh = 140,000 Wh = 140,000*3600 = 504 MJ
> 
> .... call it E.
> 
> If you are to find E from your battery bank, then...
> 
> E = current*voltage*time
> 
> E = I*V*t
> 
> Make the product of I*t the subject...
> 
> I*t = E/V
> 
> Say, for argument, your power is delivered at 12 volt...
> 
> I*t = 504,000,000/12 = 42,000,000 amp.second
> 
> = 11,666 Ah
> 
> My current house battery is 275 Ah.... that is about 1/42 of what would be needed for 6 hours motoring.
> 
> That was 6 hours motoring, and I'd need 11,666 Ah to do it, discharging the batteries to nil to do it.
> 
> My current tank capacity will keep the motor running for about 30 hour.
> 
> Pls correct me on this one there guys. Did I get it wrong?


If this is true than why are almost all cargo ships and ALL locomotives diesel/electric and have been for 50 years?

MedSailor


----------



## Wolfsong

*trolling motors*

Another short term option for using electric propulsion is a removable trolling motor. It will not push your boat very fast, but is possible to dock, anchor, tour close to shore and motor sail effectively with no noise and not having to warm up the diesel. It is not possible as the only propulsion source, but can be a great add-on. The new Torqeedo 2.0 looks sufficient for our 33' boats for that purpose.

We used a pair of EM54 Minn Kota trolling motors one season on our Pearson 33 day sail charter boat. These trolling motors on brackets wore out because they are not meant to be towed or left in the water. We did use it for 1-4 hours per day for about 70 days. With both of them on, we could go about 2.5-3 kts. It was a 24v system and would run at about 30 amps, if I remember right. On two 3 hours sails with almost no wind, we used about 200 amp hours on the heaviest days. There were weeks doing twice-per day trips that the diesel was not used at all. Our docking situation is simple, so that helped. The best part was that you can just flip a switch for instant power. We were able to sail into situations that most people would use the motor and have the instant boost of power if the wind failed us. A little boost on light wind days to get to another puff of wind, or just to get some air moving over the sails really cut down on diesel motoring.

Experimenting with electric drives is fun and will drive technology. What we need is an electric motor that works on the current drivetrain when needed. Briggs & Stratton made a brushless motor (Etec?) that was about 8 hp, worked in both directions, charging and driving, and was for golf carts.


----------



## Wolfsong

*trolling motors*

Another short term option for using electric propulsion is a removable trolling motor. It will not push your boat very fast, but is possible to dock, anchor, tour close to shore and motor sail effectively with no noise and not having to warm up the diesel. It is not possible as the only propulsion source, but can be a great add-on. The new Torqeedo 2.0 looks sufficient for our 33' boats for that purpose.

We used a pair of EM54 Minn Kota trolling motors one season on our Pearson 33 day sail charter boat. These trolling motors on brackets wore out because they are not meant to be towed or left in the water. We did use it for 1-4 hours per day for about 70 days. With both of them on, we could go about 2.5-3 kts. It was a 24v system and would run at about 30 amps, if I remember right. On two 3 hours sails with almost no wind, we used about 200 amp hours on the heaviest days. There were weeks doing twice-per day trips that the diesel was not used at all. Our docking situation is simple, so that helped. The best part was that you can just flip a switch for instant power. We were able to sail into situations that most people would use the motor and have the instant boost of power if the wind failed us. A little boost on light wind days to get to another puff of wind, or just to get some air moving over the sails really cut down on diesel motoring.

Experimenting with electric drives is fun and will drive technology. What we need is an electric motor that works on the current drivetrain when needed. Briggs & Stratton made a brushless motor (Etec?) that was about 8 hp, worked in both directions, charging and driving, and was for golf carts.


----------



## Rockter

Medsailor...

You have got this wrong. 

By "diesel electric" you are referring to a power system that has a generator, an electrical power line, and a remote motor. The reason why they do this is to avoid the mechanical engineering involved in coupling a big motor to a big prop. Also, the generator serves a power for the ship also, BUT IT IS RUNNING ALL THE TIME!!!! Diesel electric trains do it too, and for reasons of coupling also, particularly with multiple drive wheels on the loco.

What they are referring to is... and I quote...

"Picture yourself in pristine lagoons and allow the power of the sun, tides and wind to replenish your cruising. Motor away from distant fuel docks of unknown diesel quality without bating an eye. Remove your portion from our oil burden while silently cruising into distant harbors. Live the Solidnav shift, change your world. "

This is charging a battery, then running constant loss on the battery, and no-doubt having to compete with the sort of energy delivery I calculated. 
Is that what you mean by "diesel electric"? ...because that is not what ships have and not what trains have.

Where does the energy I describe come from?... does anyone plan to store even a fraction of that in a battery bank???. How far would you get before you have to start the diesel to drive the prop. When you do, you would be much better to save energy a-plenty by joining the prop to the motor by a shaft and dump the generator, cabling, and motor.

There is just not enough energy stored in the battery bank, this side of sanity.

For a submarine submerged it can work for a while... another type of "diesel-electric"... but have you ever seen the battery bank on one of those beasts?


----------



## Architeuthis

Rockter said:


> What they are referring to is... and I quote...
> 
> "Picture yourself in pristine lagoons and allow the power of the sun, tides and wind to replenish your cruising. Motor away from distant fuel docks of unknown diesel quality without bating an eye. Remove your portion from our oil burden while silently cruising into distant harbors. Live the Solidnav shift, change your world. "
> 
> This is charging a battery, then running constant loss on the battery, and no-doubt having to compete with the sort of energy delivery I calculated.
> 
> Where does the energy I describe come from?...
> 
> There is just not enough energy stored in the battery bank, this side of sanity.


You do not yet understand how these systems work. They do not need the batteries to see the reduced fuel costs and the use of batteries can remove the need for diesel.

The Solidnav system recommends using windmill generator, solar, tow drogue generator, and regenerative power under sail, to achieve the "Solidnav Shift" with no diesel. If you are sailing away from the diesel pumps you can be charging the batteries. That would be the same battery bank you could use to run other, or all, electrical items on the boat.

This "Regenerative power" is produced whenever the system is on, and the boat is under sail, moving fast enough to cause the propeller to rotate. This rotation causes the electric motor to act as a generator. You can adjust how much charging occurs once you are above the minimum speed required to generate.

This means that if winds are light you might discharge the bank to add to the sailboats speed and then recharge later when the wind picks up. It would be a different way of sailing which I expect would take some getting used to.

And the assumptions you used for your calculations are incorrect which is why your calculations and understanding appear insane. A little more research should have you seeing why these drive systems are so much more efficient. Maybe start here: solidnav.com/faqs.htm


----------



## camaraderie

I'm with Rock on this one BUT...things are getting interesting with the new battery technology and I can imagine a day in the not too distant filter where a diesel gen and electric motor, with an advanced battery bank may be the preferred way to build a boat and go to sea.


----------



## Giulietta

I think you "Einsteins" need to read more...

READ HERE to start...


----------



## Architeuthis

Giulietta said:


> I think you "Einsteins" need to read more...


Good link but we don't all figure things out the first time. I seem to recall it took Einstein a while to get his head around the need for ether.


----------



## Giulietta

Look...this is what I do for a living...so in reality...writting in this thread would be working for me...and I only work if I get paid....sorry

So that was my contribution here...signing off.

In the mean time...I find some posts really amuzing.


----------



## camaraderie

Arch... what you are saying is TOTALLY impractical on a cruising sailboat. This is so ridiculous I can't even begin to refute it. Tell ya what...as soon as someone crosses the Atlantic or Pacific with their cruising electric motor sailboat and NO diesel...let me know. The FAQ's you reference are a complete joke and lack any substantive information. This is presently smoke and mirrors.


----------



## brak

power density of combustible fuels is orders of magnitude higher than that of electric batteries we have today. until fuel cells arrive - all this electric stuff is a total bs. look, on one hand everyone runs around wondering how to reduce electric use so that running a tiny pathetic refrigerator for a day does not kill batteries. and yet someone can seriously propose pushing the entire boat with this? This is just ridiculous, no other words for it.


----------



## Architeuthis

camaraderie said:


> Arch... what you are saying is TOTALLY impractical on a cruising sailboat. This is so ridiculous I can't even begin to refute it. Tell ya what...as soon as someone crosses the Atlantic or Pacific with their cruising electric motor sailboat and NO diesel...let me know. The FAQ's you reference are a complete joke and lack any substantive information. This is presently smoke and mirrors.


This is really very old news, there isn't anything new being posted or suggested.

Electric motor sailboats have been around since, well, since before diesel engine sailboats. This technology using Pulse Width Modulation is more efficient but has still been around a long time.

And yes people have crossed oceans with this type of drive system. Solomon technologies has been around for years: _The longest-distance STI customer we know of - a retired Los Angeles physician - has been at sea for years with a battery-bank-only system and no backup generator. He has successfully sailed the Pacific to Tahiti._

This technology has been used in electric cars for years. They do not get the same regen effect because they cannot get motive power from the wind. If they were to only drive down hill I guess it would be similar.

As for the idea that it is better to have a diesel motor run a generator which then runs an electric motor for power, that is well over 50yrs old and is in common use every day.

I'm not sure why people are not aware of this. It hasn't been a secret. The only problem has been the extra cost of the installation. Like insulating your house it can be hard for some people to understand why it is a good idea but once you look you will notice that lots of people insulate and lots of people (not as many) use electric drives.


----------



## Architeuthis

Giulietta said:


> Look...this is what I do for a living...so in reality...writting in this thread would be working for me...and I only work if I get paid....sorry
> 
> So that was my contribution here...signing off.
> 
> In the mean time...I find some posts really amuzing.


I think your link to the benefit of Diesel/Electric drives has been a major contribution to anyone wanting to learn more. Thank you.

I just find some posts confusing.


----------



## Rockter

Arch...

You have got your head stuck up the wrong end of your digestive tract.

I will quote you here...

"As for the idea that it is better to have a diesel motor run a generator which then runs an electric motor for power, that is well over 50yrs old and is in common use every day".

Are you seriously pedalling the idea on this website that it is better to run a diesel engine, couple it to a generator (take the losses in generating power there), then cable the power aft (taking losses again), then covert the electrical power to shaft power via an electrical motor (taking losses again)... than to couple the diesel directly to the prop via a shaft? All those losses compound. 

Is that what you believe?

Are you serious?

You don't need to be Einstein to kick that idea up the sexual organ.

No-one is denying the existence of diesel-electric systems, but they exist primarily because of the ease of transmitting power along a tortuous (or mis-aligned) paths, or to multiple motors (on mulit-wheel power vehicles, for example). They are NOT used for their efficiency, just like hydraulic systems are not either.

On a sailboat, and it's practical, it is far better to couple the motor directly to the prop via a shaft. I promise you that a diesel electric system will NOT be as efficient, because the combination of generator, cabling, and electric motor will not be as efficient as the shaft. The generator, and the motor will heat up and throw the energy into the engine room. 

I have not seen a prop shaft heat yet, in 20 years.

This diesel electric idea, running off a big battery bank, simply cannot store enough energy. Certainly, the batteries can turn the prop for a while, but not for long. 

If my calculations are correct above.... pls correct them if not so... then just one hour 25 hp net, will need a battery bank of close to 2000 Ahr (12V base line calculation), and run to exhaustion. What will that weigh? Where would I store it? What will it cost?

I'd sooner have my diesel, and its 30 gal tank. I reckon that's worth about 58,000 Ah, and about another 8,000 Ah in each of the ship's two Jerry cans. My ship simply cannot carry a battery that big to compete.

In the dead of night, into a headwind, and chop, with the wind rising, and a young crew looking at me for what to do next, I'll settle for that, and it's just a key fob away, it charges my ship's batteries when I start it, AND IT'S MORE EFFICIENT AT TURNING THE PROP THAN A DIESEL ELECTRIC WITH THE SAME PRIME MOVER BECAUSE I DON'T NEED A GENERATOR, CABLING, AND AN ELECTRIC MOTOR.


----------



## Architeuthis

Rockter said:


> Arch...
> 
> You have got your head stuck up the wrong end of your digestive tract.
> 
> I will quote you here...
> 
> "As for the idea that it is better to have a diesel motor run a generator which then runs an electric motor for power, that is well over 50yrs old and is in common use every day".
> 
> Are you seriously pedalling the idea on this website that it is better to run a diesel engine, couple it to a generator (take the losses in generating power there), then cable the power aft (taking losses again), then covert the electrical power to shaft power via an electrical motor (taking losses again)... than to couple the diesel directly to the prop via a shaft? All those losses compound.


You Einsteins seriously need to read more.

I'll just respond to that quoted part because like smarter people before me in this thread I've had enough.

Of course there are losses in such systems but it is when they add up to less that makes the diesel/Gens more fuel efficient.

A quote from the already supplied link: _
To get started it should be acknowledged that placing a motor and generator between the propeller and diesel engine does indeed introduce new losses into the drive train. These losses can range from relatively minor to very significant and are directly proportionate to the efficiency of the motor, motor controller and generator. Different motor technologies and construction methods result in products of widely varying performance. Using a greater number of thin laminations will result in a more efficient, though more expensive, motor or generator than if they are built using fewer and thicker laminations. Similarly, saving energy in the controller means spending more on the electronic chips that control the flow of power.

It's not only a matter of spending money, but also one of developing and applying the most appropriate technologies. Some motor designs are quite efficient at one speed/load condition but drop off quickly as soon as the speed or load changes. Others have a much flatter efficiency curve. The collective impact of these differences can be huge with real operational efficiencies varying from better than 98% to as low as 72% for motors and typically between 97% and 84% for generators. This means that for every 100 HP out of the engine you could obtain as much as 95 hp at the propeller shaft or as little as 61 HP. At the high end this compares favorably with the 3% to 5% loss typical of a mechanical transmission (although not all electric motors can be directly connected to the propeller shaft).

Considering these electrical losses, is it really possible to improve energy efficiency? The answer is clearly yes, so long as the basic efficiency of your motor, generator and controller is high. What you are relying on is that you can improve the efficiency of other parts of the system by more than the new losses you have introduced. Fortunately, if the electrical system losses are relatively low, this isn't too hard to do. It turns out that there are many limitations inherent in conventional direct diesel drive that waste fuel. By making more efficient use of the engine and propeller it is possible to more than offset the electrical conversion losses.

The foundation for this saving comes from the fact that, in a well-designed diesel-electric drive system, the power required by the propeller is "decoupled" from the diesel engine speed. In other words, in a diesel-electric system, the engine/generator could theoretically be running at full speed (100% output) while the propeller is only tuning at 50% of peak speed so long as the motor is sized to handle the power. Similarly, if the propeller were lightly loaded, the engine/generator might only need to turn at low speed to provide enough energy to drive the propeller at full speed. This means that diesel-electric systems can be much better at "self-optimizing" to accommodate varying loads than are conventional systems. At sea, load conditions change by the trip (number of passengers), by the hour (wind and tide) and by the minute (going up a wave or surfing down it). These variations provide a significant opportunity for fuel savings. _

As for batteries being used, there has already been one post saying it can be done. Since many sailboats have no engine (gee I guess that too is impossible) it would seem that a trolling motor would be an an obvious improvement, but I guess not to some.

My professional associations would also suggest I charge for this.

Or are you guys just kidding? You must be joking, people cannot be that opinionated and ignorant at the same time.

HaHa you got me but thats the last time in this thread, try another.


----------



## CalebD

What about that Swiss (non-sailing) catamaran that crossed the Atlantic using (I believe) only solar power to drive electric engines? I believe that they covered the whole boat with solar panels and are now touring the states. The trans Atlantic trip was done to prove the concept although I know none of the technical details.
Are there commercial ships using the diesel-electric marine power set up that Giu/Alexa mentioned? If the big boys are using it already then it can't be too long before it comes into wider use.


----------



## brak

There is a difference in terminology here that probably creates some miscommunication.

When diesel generator drives electric propulsion, what we have is in essence another type of transmission - mechanical, hydraulic and sometimes electric. It has its advantages and disadvantages, I am sure. 

This is not the same as true electric propulsion - which really isn't so much about the motor but about the fact that energy is stored not in a form of liquid combustible fuel, but in a form of electricity stored in a battery. 

The former is a viable transmission option. The latter is not viable at the current level of battery technology.


----------



## artbyjody

There are only two kinds of electric propulsion.

1. Totally powered by renewable resources using the batteries as the storage.

2. Hybrid where mechanical means are used to generate electricity and charge the batteries - sometime in combination with solar, wind, turbine power.

There are no others.

The company in question - has very much the same mantra as Re-E-Power. And for further clarification - electric propulsion is usually defined as that powered by the batteries where a sail drive propulsion is categorized as being that which has mechanical assist from aux gen sets.


----------



## brak

Let's look at this from another direction - weight vs range. 
So, my boat currently has an approx. 50hp (50kW) engine and a 50-60 gallon fuel tank (it's inside the keel, and I don't know for sure as I try not to go on empty, the fuel on the bottom is pretty nasty). 50-60 gallons of diesel (at 7 lbs a gallon) weight something like 350-420 pounds. 

Now, the engine from E-POD system (they had a spec) provides an equivalent of 7-9 hp outboard (yikes) and has a max. continuous amperage of 170 amp (and recommended cruise amperage of 50 amp, which clearly would provde about 30% of max power, or 2-3 hp). It is also 24-48v, which of course makes a lot of difference, but let's assume 24v somehow (24v * 50amp = 1200 watt, or 1.2 kw or about 1hp, at 48v it's 2 hp - but hey, 1 hp is aplenty for a boat, right?). 

Ok, so 50 gallons of fuel last me from 50 to 75 hours. Let's go with 50, just to give electric a headstart. We'll need 50*50 = 2500 watt-hours of 24v electricity to run this thing. Now, modern battery amp hour ratings are given at 20 amp draw (and go down with higher draw) but we'll assume the best. So, our favorite 6v golfcart dekas are 215 amp hours each. We would need 4 times each for 24v and then 12 times groups of 4 for 2500 watt hours. Total of 48 batteries. At 65lbs each, thats about 3000 lbs. I suppose if you replace the ballast with batteries that might just work  3000lbs may be a bit difficult to stow though, what with carrying each of the 48 batteries. Of course since you can't discharge the batteries all the way (unlike the fuel tank), you need twice as much - 100 batteries, 6000 lbs  

Of course that just gave us a system that is 50 times less powerful (1hp vs 50). For more power, don't forget to multiply the battery count and weight times 50   

With current lead-acid battery technology, electric propulsion is just not there. Anyone trying to sell it is either a crook or a nutcase.


----------



## capttb

I used to have an electric Ford Ranger available for my use (because everyone else hated it) that I drove whenever possible. Only had three drawbacks, the batteries, the batteries and the batteries. They were really heavy, discharged too fast even with regenerative set at max, and took 10 times as long to charge as they would run. Only repair for any breakdown (there were several) was a tow to Ford Motor Co., you'd get in and it was just dead. No way to troubleshoot or duct-tape a repair. Until we get giant Li-Ion laptop type batteries or dependable fuel cell I'll stick to diesel. If worse comes to worst you can always homebrew a little something that'll make it run long enough to get to sea.


----------



## Rockter

I will stick to my Volvo, shaft drive, alternator, and 30 gal diesel tank.

You are welcome to your revolution.


----------



## Architeuthis

This was actually a very informative thread. Not so much about technology but how it is perceived. Thanks.


----------



## brak

I find it interesting that a pro-electric-propulsion side prefers to talk about perception, rather than provide any numbers. I am sure that means something, but I can't quite put my finger on it


----------



## Architeuthis

brak said:


> I find it interesting that a pro-electric-propulsion side prefers to talk about perception, rather than provide any numbers. I am sure that means something, but I can't quite put my finger on it


We never got there. People haven't got past the point of understanding that these systems are already proven, used for over 100yrs, used in most of industry (including the shipping industry) and used every single day in everything from trains to the car down their street.

It is a very long way from that to talking about the numbers. Those numbers are not can it be done but is it cost effective to use on such a small scale as a 5 ton sailboat. It seems so given the success of the 420 Cat but is it for a conversion? Maybe.

Still talking about how impossible such systems are preclude any discussions about numbers. At least numbers of value. Look at the numbers used so far, they mean nothing. When people refuse to even read the link explaining the reality of such systems it is safe to say that posting numbers is best saved for another thread.

Maybe start another thread? It is going to be hard to get this one to be taken serious.


----------



## GreenEgg

Architeuthis said:


> This was actually a very informative thread. Not so much about technology but how it is perceived. Thanks.


Interesting comment.

I agree.

Intelligent people can see a sales pitch of an, shall I say, 'undeveloped product', when it hits them in the face. 
If it doesn't actually work more efficiently than current technology, it doesn't have a hope.

Keep working on it, and get back to me in a few years.
Good luck.


----------



## brak

Ok, more wishy-washy stuff, no numbers still. I am not aware of any significant number of large ships that use battery-stored electricity as their source of energy, but perhaps you can point me in the right direction.

I would also be interested to see a simple and specific example or proposal on powering a small craft (such as an average sailboat) using electric propulsion with battery stored energy, for a realistic use profile.


----------



## brak

BTW, it looks like lithium-ion batteries may not be much better in terms of energy density. A search on the web revealed a company that makes large capacity li-ion batteries.
A 15v 160 amp-hour battery weights about 38 lbs. Thats not too different from similar lead-acid battery (perhaps a little more, actually).


----------



## TSOJOURNER

Hybrid power is a solution looking for a problem. The technology as applied to sailboats, needs time to mature at the very least. Yes, diesel subs and EMD offshore supply boats have been around for ages but the technology as applied to sailboats is very new. Diesel subs could only stay under water for so long, and then they had to return to the surface so their batteries could be recharged by a diesel engine. Ice breakers, locomotives and offshore supply vessels that use EMD systems have very large diesel engines attached to a very large generator whichis then attached to a very large propulsion motor...which amounts to a large percentage of a vessels displacement and a subsequent loss energy as heat energy. The application for sailing yachts is very different from the previous applications and this is the critical difference.

Converting mechanical energy to electrical energy, to then be used or stored and then converted back to mechanical energy is inherently very inefficient. Each time energy is converted, part of that energy is lost as heat energy. Even if a boat could be run purely off solar and wind energy, one must consider the increased number of batteries in terms of additional weight added to the boat and pollution to the environment in the process of making those batteries.

Another factor is sustained cruising, where within a 24 hour period, with a hybrid boat you are limited to the generators output minus your shipboard loads, minus the inefficiencies. Hey, stuff happens and the iron jenny becomes necessary for hours and sometimes days. An eight kW generator is the equivalent of 10.8 horsepower minus any inefficiencies in converting watts to mechanical energy and minus the shipboard load. With a 20 kW generator, the equivalent horsepower is 27.2 horsepower. Is it feasible to place a 20 kW generator aboard a sail boat that only needs less than a 27 horsepower engine for its propulsion?


----------



## Rockter

Arch...

Start another thread. 

Start it with the battery calculations.


----------



## hertfordnc

Forgive me for not wanting to see this thread die....

I can't help thinking the discussion missed certain marks.

1. A boat does not have to cross the Atlantic to be good for it's intended purpose. 

2. Some people just sail for fun. It's not always a fight to the death with the elements to test ones manhood. 

3. Typical sailboat usage is a truly IDEAL application for electric propulsion. We fire up the motor, leave the dock, raise the sails, turn off the motor- repeat in reverse. Leave boat at pier for several days to recharge. For a lot of people a golf cart motor would be great. 

4. The advantages to a successful electric propulsion system are so incredible it is certainly worth a considerable effort to make it work- 
a. instant start 
b. almost no winterization
c. QUIET - (sneaking out of the marina a 0500 without annoying the livaboards)

5. Many of the above argument was based on a comparison to large diesel/electric systems but that's not what we are talking about. This would be a primarily electric system with a small motor to recharge the battery bank for extended motoring. Many people would not need the motor. 

6. For all the pro and con arguments presented- where is the guy who bought the system and can now say if it does or does not work? I'm thinking maybe this exchange was so hostile that guy chose not to participate.

Perhaps my perspective comes from the advantage of being unencumbered by knowledge or experience.


----------



## camaraderie

hertford...right...in and out of the harbor on the weekends is an ideal application though not without its problems as well. We were arguing about cruising applications and regenerative power of passive sources...not whether short term "18 holes and recharge at the dock" uses are practical.


----------



## Rockter

But you will not get extended motoring without a huge battery bank.
What is meant by "extended motoring"? 
Just one hour motoring on my ship would, I reckon, ask me for about 1900 Ahr.
From where will I get that?
My engine uses one gallon of diesel by comparison.
One hour is not very long in this game.
The idea that a reversible reaction in a battery can compete with the violence of diesel combustion is dream land. It cannot. There is simply so much more energy in the diesel combustion. A gallon of it weighs about 7 lb. What does 1900 Ah of battery weigh?, and that's for one hour only.


----------



## SolidNav

*Smoke and Mirrors?*



camaraderie said:


> Arch... what you are saying is TOTALLY impractical on a cruising sailboat. This is so ridiculous I can't even begin to refute it. Tell ya what...as soon as someone crosses the Atlantic or Pacific with their cruising electric motor sailboat and NO diesel...let me know. The FAQ's you reference are a complete joke and lack any substantive information. This is presently smoke and mirrors.


One, I am the President of SolidNav.com
Two, Sailnet has been, and will again, go out of business.
Three, I will not be advertising with them(abusive and ridiculous moderator on this forum proved that point well).

You are right in one aspect, we are not the alternative for you. As a matter of fact, we are not really an alternative for anyone with new 52' Tayana stinkpots that happen to have a sail.

If you are that dependent on an engine, quit lying and buy a trawler. Rename the site as "trawlernet" and we can move on honestly.

Your comment about traveling oceans with electric is ludicrous. My largest sales objective in the Uk is to convince them that they even require an engine (there are some true sailors there). Ask guys like Hal Roth and other actual sailors about motors and your answers will be very, very non-nondescript.

The truth is for you and your boy Barak, is that the knowledge base on electric boats is very vast. Your arm chair naval architecture runs into a common fallacy, it doesn't work. Every single mathematical equation and formula, for every boat and every owner cannot accurately describe the behavior of a boat moving through the water. I avoid using anything but actual test data that I have been involved with myself.

Before you amble off into illogical power boater rants. Please feel free to contact one of the hundreds of boat owners worldwide comfortably sailing in their electric yachts.

Under a different name and in a different circumstances, I have quietly seen the bullying attitude by those that think they own the ocean and the seas on sailnet's forums, this is my retort. We are not the first alternative just for guys that can afford new Beneteaus (or Tayana's), we are here to help everyone enjoy _sailing._

Enjoy your fuel burning and wrench turning! The tide is changing with or without you. Look for us on store shelves around the nation.

Any sailor that would like to ask me any questions, about my product or any other electrical install that they are working on with any product, feel free to shoot me an email. I love to help.

Jason L. Russell


----------



## Giulietta

Ahhh I just got me some pop-corn and now I wait the show to begin...



SolidNav said:


> One, I am the President of SolidNav.com
> Two, Sailnet has been, and will again, go out of business.
> Three, I will not be advertising with them(abusive and ridiculous moderator on this forum proved that point well).
> 
> *I agree they are ridiculous, specially the red neck from texas....the other one not so much....he's just ugly*
> 
> You are right in one aspect, we are not the alternative for you. As a matter of fact, we are not really an alternative for anyone with new 52' Tayana stinkpots that happen to have a sail.
> 
> *AHAHAHAHA that was funny...C'mon Cam he was funny...*
> 
> If you are that dependent on an engine, quit lying and buy a trawler. Rename the site as "trawlernet" and we can move on honestly.
> 
> *Ahahahahaha that was funny too....*
> 
> Your comment about traveling oceans with electric is ludicrous. My largest sales objective in the Uk is to convince them that they even require an engine (there are some true sailors there). Ask guys like Hal Roth and other actual sailors about motors and your answers will be very, very non-nondescript.
> 
> *I am from Europe...and so far only saw a Cat with the hybrid motor...we had to tow him back to port...but you are feisty*
> 
> The truth is for you and your boy Barak, is that the knowledge base on electric boats is very vast. Your arm chair naval architecture runs into a common fallacy, it doesn't work. Every single mathematical equation and formula, for every boat and every owner cannot accurately describe the behavior of a boat moving through the water. I avoid using anything but actual test data that I have been involved with myself.
> 
> *Who is the boy Barak??? Now I am confused...*
> 
> Before you amble off into illogical power boater rants. Please feel free to contact one of the hundreds of boat owners worldwide comfortably sailing in their electric yachts.
> 
> *OK...phone and email of each one of them...*
> 
> Under a different name and in a different circumstances, I have quietly seen the bullying attitude by those that think they own the ocean and the seas on sailnet's forums, this is my retort. We are not the first alternative just for guys that can afford new Beneteaus (or Tayana's), we are here to help everyone enjoy _sailing._
> 
> *I have an aquarium...does that count???*
> 
> Enjoy your fuel burning and wrench turning! The tide is changing with or without you. Look for us on store shelves around the nation.
> 
> I *also like the Scorpions..the winds of change....the tides of change..never heard...but you're funny...*
> Any sailor that would like to ask me any questions, about my product or any other electrical install that they are working on with any product, feel free to shoot me an email. I love to help.
> 
> Jason L. Russell


Alex Da Gama de Cabral Magalhaes Colombo

.


----------



## artbyjody

SolidNav said:


> Any sailor that would like to ask me any questions, about my product or any other electrical install that they are working on with any product, feel free to shoot me an email. I love to help.


With that tirade, being CEO, President or whatever, and all - do you really think many of us would want to do business with someone that so belittles everyone with such a condescending tirade, especially after being here on another screen name. Obviously, you didn't read the rules here about joining. Secondly - a good business person as soon as this question from the OP would of come up, would have in due diligence, posted actual answers to questions posed. Instead, you opt to still not do it period and relent upon a discourse that frankly represents some of the worse behavior a customer would never hope to intertwine with.

You insult any-one on here - odds are that many more of us - such as myself, will easily skip by any product you may have much less now any actual valuable input that you could of presented.


----------



## Giulietta

artbyjody said:


> With that tirade, being CEO, President or whatever, and all - do you really think many of us would want to do business with someone that so belittles everyone with such a condescending tirade, especially after being here on another screen name. Obviously, you didn't read the rules here about joining. Secondly - a good business person as soon as this question from the OP would of come up, would have in due diligence, posted actual answers to questions posed. Instead, you opt to still not do it period and relent upon a discourse that frankly represents some of the worse behavior a customer would never hope to intertwine with.
> 
> You insult any-one on here - odds are that many more of us - such as myself, will easily skip by any product you may have much less now any actual valuable input that you could of presented.


Leave him alone...he's funny and he is protecting his product....


----------



## artbyjody

Giulietta said:


> Leave him alone...he's funny and he is protecting his product....


What product? Bite Me Gui, and stop letting that ******* stuff get to you


----------



## Giulietta

artbyjody said:


> What product? Bite Me Gui,


*IT'S GIU DAMN IT........................*


----------



## engele

Wow, I never really meant to start such a stupid flame war over this. For me the Technology already has been proven (as many have stated on this thread). I was hoping for more of an intelligent discussion, and really hoping for comments from those who had installed Asmo, Soloman, Solidnav, or other systems.

Solomon Technologies has been around for years, and their systems are factory installed in several boats (Lagoon catamarans for example). I have also previously heard good things about the Asmo systems.

More in line with my intentions would have been a discussion on things like:

What batteries are electric sailors using? Lithium Ion, Nimh, sodium, etc.

What is there "measured range" with the batteries they have and the system and boat they have?

What about the home built guys? which motor did you use, controller, etc. What problems did you have?

The fact that many systems are already (and have been for quite some time), being used and sold, lays to rest the argument that it cannot be done. On top of that, these motors are installed in a wide variety of boats, and that does include ocean capable cruisers.

This discussion is awfully reminiscent of discussions I have heard on catamarans and their cruise potential. For many years people said that catamarans were not safe for offshore sailing. 

That is still often debated, but cats have done the loop. For me, the question isn't a question of fanaticism or blind idealism, but one of practicality.

I grew up with a small fishing boat that was powered by a trolling motor. it worked great. There is no reason the concept can't scale. On top of that, what is the longest amount of time that anyone on here has run their engine?

For me it is about seven hours, and only then it was because I needed to get across the bay and back to work the next day.

I can't see motoring for days on end. Maybe that is Naive, but I don't think so. I also have known sailors who had Atomic Four engines that only worked about a third of the time they went sailing.

Also whenever a sailor would be tying up at a dock, they would normally have shore power available (even outside the USA) and can use that to quickly charge batteries.

For those who say you can't cruise with an electric engine, I guess I disagree. On a passage where you stay on one tack for days on end, why can't you be taking on a trickle charge from solar, wind and regen?

A combination of power sources isn't a bad option. Also the weight of many gas engines offsets the weight of an electric.

Yes, you need a lot of batteries for a lot of range. So what? In any case the dialog here has gotten wayyyy too opinionated. 

I should have known better than to post on something that I know is controversial. Sailing traditionalists are not early adopters of technology (not that that is always a bad idea).

I like the concept of electric drives, and judging from my own use, I would never have a problem with the technology as is. Also battery technology keeps getting better. Those factors combined mean that I will likely install one of the Solidnav systems.

These discussions are popping up everywhere on the web lately. I expected a more technical discourse on sailnet.

Oh well,

Cheers, and may you all calm down and not die of high blood pressure,

-EE


----------



## Giulietta

So..I have a question for Solidnav, not joking this time.

How much would the weight be, including batteries, motor etc, for a 12.500lb total weight 42 footer, so that the power output be equal to 40HP and installed with a saildrive?

Thanks


----------



## chucklesR

SolidNav, 
let me introduce you to a concept called 'customer service'.
If you sold a product that converted air to gold I would not do business with you or yours.
That is not in defence of 'my' moderators, that's because rather than state facts you choose personal attack making it obvious to me you have no facts.

How does someone become president of a company without first growing up and learning a little business acumen?


----------



## brak

If I were to venture a guess, I'd say that Jason is a President as well as the sole employee of this company. Sounds like his education is limited to high school (and he did not take physics). Also, while I am no visionary, I bet $100 this company will be out of business within a year. 

And I certainly take offense to being called a "boy Barak".


----------



## Giulietta




----------



## SolidNav

brak said:


> If I were to venture a guess, I'd say that Jason is a President as well as the sole employee of this company. Sounds like his education is limited to high school (and he did not take physics). Also, while I am no visionary, I bet $100 this company will be out of business within a year.
> 
> And I certainly take offense to being called a "boy Barak".


I will certainly take that bet....and I will raise.

I take offense to you laying into everyone that posts here. I have been watching for years and wondering when you guys have time to go sailing. Everything you said above is false and really not worth discussing. Your moderator attacked someone who was looking for information, you have as well. You are not my customer and never will be. My customer service, to people other than those who spew information without looking at any for any sources, is very hands on and in depth. GIU made an excellent point with his diesel electric link, you should read it before insulting people who were very polite to you.

Here is a fair challenge:

I will give Sailnet an engine at cost, fly to the boat of their choosing, install the system for free and let them report as they see fit.

Now I am off to answer Giu's fair question.


----------



## buckeyesailor

sounds fair..........

note to sailnet:......Choose me!


----------



## SolidNav

Giulietta said:


> So..I have a question for Solidnav, not joking this time.
> 
> How much would the weight be, including batteries, motor etc, for a 12.500lb total weight 42 footer, so that the power output be equal to 40HP and installed with a saildrive?
> 
> Thanks


Well, I haven't pushed one through a saildrive. Interesting. Do you know the gear ratio and how the input shaft would connect? We are designed to couple to an existing propeller shaft. Is it a sled? 12,500 lbs is certainly light. Our voyager system is design to replace diesels in that range and would perform nicely. Your battery weight and size is dependent upon your desired range and speed at which you wish to travel.

The engine itself will weigh in about 140 pounds (the larger engine is still under development, so final weight is an estimate) and your batteries around 1,000. That is for 16 lifeline AGM's. If your range is shorter, you can run 8 batteries and your weight drops to around 650lbs total.

Now, here is the stickler, a boat that light may not require the Voyager model, it may be a much better fit to use the Explorer.

Lets talk little about the boat, what kind of wake is it pushing? If it is a narrow sled, we may be in excellent shape to reduce the batteries required. Some customers with race boats install 4 12 volt batteries to push them off the dock and around the marina, saving a great deal of weight overall.

You can do that job for a couple of hundred pounds.

Tell me a bit more about the boat and its intended uses and I can get more specific.


----------



## SolidNav

buckeyesailor said:


> sounds fair..........
> 
> note to sailnet:......Choose me!


What kind of boat? If it works, why not? Its up to you sailnet.


----------



## Giulietta

SolidNAv, the boat is this: It's a planing hull.









































































The engine I have now is a Yanmar 3JH 4E with a racing SD50 light Saildrive.
I chose this engine because it weighs complete 460lbs, including the saildrive.
The ratio is 2.32/2.32, mechanical cone clutch...Its a superb engine. let me tell you. Its quiet, fast and economical. Pushes the boat to 9.5 knots at full speed.

You can read about the boat

HERE

HERE

HERE

There is no way I will ever go for a heavier arrangment. Sometimes the boat needs to sail to ports that are 80 miles away and uses the engine (ferry)..so there is no way I will rely my boat on a system that may not work if needed, so the batteries need to be calculated to provide a minimum of 6 hours drive.

I am only interested if you can save me weight...no need to worry with comsumption or anything else...all I need is weight reduction and at least 6/8 hours drive on one charge..

Get 10 posts so you can use the PM feature here and I will send you the engine tech data pdf file.


----------



## Rockter

You can talk power and weight until your ears pop, but how FAR... you know... DISTANCE.... like VELOCITY multiplied by TIME... does it move the ship?

The video talks of about 8 by 6V by 280 Ahr and that will be 13440 Ahr at 6V, ...allow me to halve it to 6720 Ah at 12V equivalent ???

I work that out to be about 3.75 hr from the diesel, assuming full discharge of the battery bank.

If I heard you right, the battery bank might weigh about 1000 lbf.

That would take my ship about 22 miles, in settled conditions.... 3.75*6.

The ship is 11 tonf.

Now how does that compete with a range on the tank of about 250 miles?

Does it attempt to compete?

Your problem is energy storage... the age-old problem of batteries... they struggle to store enough energy. There is no problem with the electric motor, it will be more efficient than a diesel. The problem in competing is that the diesel draws from a very much larger energy storage.

When that energy comparison problem is narrowed, or your potential users do not need much range, then you are in a strong position. Be up-front with the range limitations though, because for many owners, such limited range would be crippling. My ship simply could not get by on that. It is not far enough. If I dropped speed and that range doubled to (say) 44 miles, it still would not be far enough.

A potential user really must know how far it is going to move his ship is reasonable motoring conditions. They will be less interested in how quiet or how clean it is.

And when energy storage calculations are offered (and offered as open to edit), counter with your own.


----------



## chucklesR

I'm getting tired of this outright advertising, especially via obvious ho undeclared proxies - especially with the tones.

Facts, SolidNav, post the* facts*. Giu's given you a good start on a racer cruiser.I'm sure someone can give you spec's on a monohull cruiser (obviously you have no experience with long range cruisers).
I have a pure cruiser, albeit a weight sensitive catamaran.
I sail a 2007 Gemini 105Mc, Performance Cruising Inc. - The Official Gemini 105MC and Telstar 28 Web for specifications. My immersion is 900 pounds per inch. I can not accept more weight than my current system unless I sail naked with no food or water. My current batteries are 3 Optima's at 70 pound each on the house, and one 70 pound starting battery. 280 pounds total, all on the port side. Weight balance is important because the 900 pounds per inch of immersion is actually 450 per hull.

Tell me you have a system that moves my boat for the same range at the same speed . I've got 36 gallons, 7.2 knots, estimate at 1.12 gallons per hour on my Westerbeke 30b, I can carry an additional 20 gal easily on deck and I can refill in less than a hour. 
Call it 60 hours at 7.2 knots or 430 miles of range with a 1 hour (refill) recharge time. I'll spot you the 240 bucks it takes to refill at 4.00 a gallon. I'm not talking 1/2 hour of motor to get to the dock, I'm talking motoring along for 3 weeks to get down the ICW to cruise.

Your system seems to be fine for the day sailor that runs the motor for a hour or two a day, and has a week at the dock to recharge - it's not ready for prime time on a real boat. Your comment above about the people on sailnet not being real sailors lends me to ask what your qualifications are? Certainly not customer relations or salesmanship; doubtfully anything with sailing attached.

If you coat my available deck space in solar I can maybe get 4 more 130w panels without having to walk on them, adding in a wind gen doesn't even power your motor for day; run a water maker, nav lights, interior lights and other necessary items on a cruiser and I have to ask -

what size nuclear power plant are you installing on these systems?


----------



## brak

SolidNav said:


> My customer service, to people other than those who *spew information* without looking at any for any sources, is very hands on and in depth.


 I am sure anyone that has any information is not a suitable customer for you  Information is something you avoid at all costs.

I will take you bet as well. See you in a year


----------



## camaraderie

Rock...picture a Catalina 27 with a 10HP outboard or similar sized inboard. 
Engine use is 20 minutes in and out of the harbor on the weekend. 
Rest of the week...plugged into a dock. 
A big battery bank and an electric engine may be a very good idea for this crowd as opposed to the cruising crowd....especially as quick charge, deep cycle, long life batteries begin to hit the market. 
Not saying I'd ever buy one...but that is the only application i can think of for electric in the sailboat market that makes any sense with current technology.


----------



## camaraderie

SolidNav said:


> One, I am the President of SolidNav.com
> Two, Sailnet has been, and will again, go out of business.
> Three, I will not be advertising with them(abusive and ridiculous moderator on this forum proved that point well).
> 
> You are right in one aspect, we are not the alternative for you. As a matter of fact, we are not really an alternative for anyone with new 52' Tayana stinkpots that happen to have a sail.
> 
> If you are that dependent on an engine, quit lying and buy a trawler. Rename the site as "trawlernet" and we can move on honestly.
> 
> Your comment about traveling oceans with electric is ludicrous. My largest sales objective in the Uk is to convince them that they even require an engine (there are some true sailors there). Ask guys like Hal Roth and other actual sailors about motors and your answers will be very, very non-nondescript.
> 
> The truth is for you and your boy Barak, is that the knowledge base on electric boats is very vast. Your arm chair naval architecture runs into a common fallacy, it doesn't work. Every single mathematical equation and formula, for every boat and every owner cannot accurately describe the behavior of a boat moving through the water. I avoid using anything but actual test data that I have been involved with myself.
> 
> Before you amble off into illogical power boater rants. Please feel free to contact one of the hundreds of boat owners worldwide comfortably sailing in their electric yachts.
> 
> Under a different name and in a different circumstances, I have quietly seen the bullying attitude by those that think they own the ocean and the seas on sailnet's forums, this is my retort. We are not the first alternative just for guys that can afford new Beneteaus (or Tayana's), we are here to help everyone enjoy _sailing._
> 
> Enjoy your fuel burning and wrench turning! The tide is changing with or without you. Look for us on store shelves around the nation.
> 
> Any sailor that would like to ask me any questions, about my product or any other electrical install that they are working on with any product, feel free to shoot me an email. I love to help.
> 
> Jason L. Russell


Mr. Russel...you have attacked me personally and my boat which is a violation of sailnet rules and I could delete you and your post. 
Instead I choose to memorialize it here within a post of my own so that you can never go back and delete your own words and so that the 100,000+ members of sailnet will ALWAYS think twice about doing business with your company. Should electric become a viable option someday...those sailnetters will be able to see exactly what kind of person YOU are and make the choice of another electric vendor. 
I choose NO ONE to receive your product...if you want to give one away...some one here can e-mail you and you can pick them. I will have no part of it. 
I also choose not to let you further use this forum to advertise your wares. 
You...as all vendors...may respond to direct questions from members about your product. You may NOT initiate conversations about it or in any other way promote it. These are the rules for ALL vendors here and you will be held to them. 
Further personal attacks on me or other members will result in your being banned. Stick to the facts in your posts or stay out of this forum.


----------



## SolidNav

Giulietta said:


> SolidNAv, the boat is this: It's a planing hull.
> The engine I have now is a Yanmar 3JH 4E with a racing SD50 light Saildrive.
> I chose this engine because it weighs complete 460lbs, including the saildrive.
> The ratio is 2.32/2.32, mechanical cone clutch...Its a superb engine. let me tell you. Its quiet, fast and economical. Pushes the boat to 9.5 knots at full speed.
> 
> You can read about the boat
> 
> There is no way I will ever go for a heavier arrangment. Sometimes the boat needs to sail to ports that are 80 miles away and uses the engine (ferry)..so there is no way I will rely my boat on a system that may not work if needed, so the batteries need to be calculated to provide a minimum of 6 hours drive.
> 
> I am only interested if you can save me weight...no need to worry with comsumption or anything else...all I need is weight reduction and at least 6/8 hours drive on one charge..


Firstly, give me a minute to put my tongue back into my mouth and wipe the drool from my chin. That boat is gorgeous beyond rational comprehension.

Now for the bad news, the Explorer is probably not a good fit for your boat. Your weight and range might be met by pulling off the leg but you would need to install a propeller shaft to use the Explorer. It is geared to a good speed now and the leg would gear it down to far.

Honestly, the best electric choice for your application is the Re-e-power system. I do believe that electric installs are good for the industry in general, so I do not mind sending people to competitors if it is a better fit.

You need to calculate your weight including engine, leg, fuel tank, full wet exhaust, spares, full fluid engine weight, extra tools required for maintenance, full intake lines, sea strainer and of course the stiff drink to combat the shock of fuel dock prices. You may be able to slim a pound or off of it but you would loose the top end performance that you are used to.

That being said, you have a nice little engine there, I wouldn't change it without a really good reason.

Now, I am going to go back and stare at your pics for awhile.


----------



## TSOJOURNER

Well gee Mr. Russel, I need to tell you that you have not left me with a very good impression of your firm, nascent though it may be. It has been my experience that the attitudes and practices of the owner/operator tend to become entrenched as company policy.

This Sailnet Forum is only one of hundreds of thousand of situations you are going to encounter where you will need to create interest in your product and then educate your audience.

The skepticism you encountered here was not especially abrasive or ignorant. As irritating as you may find the tone of some folks, they have as much right to speak and be heard as any of the rest of us. Learn to deal with those people gracefully, or your business does not have much hope of succeeding. If you plan to accomplish anything in this world, you need to cooperate with others. If you plan to accomplish a lot in this world, you need to be able to inspire people and lead them. The foundation of that is a respect for your fellows.

Anyway...

I mention this because I am exactly the type of boater that you are hoping to sell your product to - vaguely tree-hugging, not too conventional and willing to invest in new things. I use the engine on my boat solely to get in and out of the slip, and even then, only if I have to.

About three years ago I researched this topic fairly thoroughly. I came to the conclusion that until fuel cells became practical, electric propulsion was not for me. There are lots of boats out there that rely on electricity quite successfully, but the one thing that I want from the engine is the ability to get out of a tight situation if I should find myself somewhere that the sails won't work. In order to pack that kind of power, I would need to carry heavy duty batteries. Or a fuel cell, which is possible right now, but they generate a lot of heat and it's a royal PITA to get the fuel for them.

During the research, I contacted a lot of companies. When I do install an electric system (notice I said when not if) I will install ASMO because the gentleman took the time to respond to my email, was totally honest about what he did and didn't know, made no outlandish claims and just seemed like an all-around easy guy to deal with. In contrast, the people at Solomon wouldn't give me the time of day.

I believe that I printed off the ASMO emails and filed them away somewhere for future reference.

I don't think that your product is a pie-in-the-sky pipe dream.

I didn't look at your site because I had decided to buy ASMO and now I am even more determined to buy ASMO. 

I would suggest that if you are going to post on various sailing forums in order to generate some awareness of and interest in your product, a more successful approach might be to ask people for their opinions, or better yet (especially here on Sailnet) ask for help solving problems you are encountering.

I would imagine that a post something along the lines of "I have this great propulsion system and am wondering if anyone can suggest a great electrical power storage solution" might get considerably more positive responses than you have so far received.

Have you contacted Max-Power to see what is happening with their portable fuel cells ??? To me - it is a no brainer that you would be bundling and selling with them.

In closing, don't insult or otherwise abuse the moderators. They are very popular folk here, as are the moderators on other forums. Really - you shouldn't abuse or snarl at anyone. It's very, very bad business practise.

Good luck ! 

(_You're welcome_)


----------



## brak

Wow, those max power fuel cells are certainly pretty close to being a product I'd buy. The temperature limits and cooling requirements are the only real issue. Thanks for the pointer


----------



## sailaway21

MedSailor said:


> If this is true than why are almost all cargo ships and ALL locomotives diesel/electric and have been for 50 years?
> 
> MedSailor


Actually I'm unaware of *any* cargo ship being built as diesel-electric ever. The T-2 tanker of WWII vintage was turbo electric wherein the steam turbine powered an electric motor. The only benefit was that it made the engine direct reversing. Virtually all modern cargo ships are direct drive, slow speed diesels.

The only advantage to using a diesel to then run an electric motor is to optimize the speed of the diesel for efficiency. Since most vessels at sea rarely change the speed of their motor, including ships and boats here, a properly designed diesel is designed for maximum efficiency at the vessel's sea speed.

I fail to see the advantage of any type of electric drive given current technology and the diesel-electric idea is so popular that no one is doing it on ships. In boats, less advantageous even yet.

Another not so minor detail is that these motors need to be DC and to be efficient they need as large a DC voltage as possible. DC voltage at high levels is nothing to trifle with, particularly at sea.


----------



## sailaway21

Mr. Russel,
I was casually reading this thread when I came across your first post to it. Had it been a post by some otherwise new member I might have taken a moment or two to slap him around a bit verbally for his tone and presumption. But since you seem to take yourself seriously, as well as your product, I'll just mention that I couldn't imagine doing business with you based upon your first post.

In my business I work with strangers every day and I get paid quite well working for them. And they really need my services, since they have no water to their domiciles. And I also like to think that I'm pretty damn good at what I do. Yet, if I addressed one single customer in the manner you have addressed the entirety of sailnet my owner would drive out to whatever job I was on just to fire me-and I've been with him for six years.

If you're smart you're in business to make money, irrespective of the product. If you're willing to get smarter, you'll soon realize that tolerating fools and never losing your cool with customers and potential customers is a requirement for running a successful business. I don't care if you invented air; with the attitude you've displayed you won't be able to give it away.

Now you wouldn't be the first, or the last, person to get off on the wrong foot here. But given the fact that you're trying to sell a product here, or at least a concept, I feel owed an apology and one for my friends as well. Perhaps, with that in hand, we can then move forward on discussing your ideas. Absent that, I will say good day to you, sir.


----------



## engele

*Honest dialog*

Well I have to say. Whatever people think of the concept, or the reactions of others here on sailnet, I am glad that at least people are saying what they think. Irrespective of Jason's views (which are often different than my own), I think that this is a concept who's time has come.

It is sad to see such a negative slant to the dialog. I feel that there is little I can do to steer this discussion back to where I wanted it because I know Jason at Solidnav. That is unfortunate, because a discussion on the benefits of electric propulsion, vs. the pitfalls would have been great to see (and that was my intention, using Solidnav as a base).

Jason just was fed up with the snarky comments I guess. It doesn't help you make friends with those who disagree with you, but then maybe that was a hopeless cause anyhow.

I think that many people (like one of the posters above), have already decided to go electric, and were just waiting on the price point to lower to an acceptable level on a product with enough fit and finish to get the job done reliably.

There are a lot of boats that have done this. Yahoo has an electric boat group, and there are articles from DIYers all over the net.

The fact is that many people want to buy a product with the engineering. welding, cutting, bolting etc. all done. I happen to be one of those people, though I have considered building my own system several times over the years.

The technology isn't new, but things like adjustable motor mounts, safety covers, sealed potometers and the like are all things that are nice to see in a package. When compared with the homebuilt systems these features make all the difference, not in overall function maybe, but in the simplicity of the install.

Generally, I like all of the electric options. I am not a fan of some of the more abstract designs just because I think that complexity leads to broken components, but all of the ones that use a few basic points look good to me.

My criteria are:

a reduction gear
sealed components
brushless motors
adjustable motor mounts
use of existing controls

There are several companies that offer all of those features. I tend to think that Jason has put together a good package. The components are solid and the overall price is fair.

Anyhow, enough with opinions (there are enough of those). I suppose there is little chance of reviving this discussion with people who have gone through with the upgrade, or have looked into doing it and decided not to for whatever reason.

oh well,

best regards,

-EE


----------



## Rockter

The system in the top video is not a diesel-electric.

It is an electric motor running off batteries.

How far will it take my ship?... 11 tonf, double ender, long keel with cutaway forefoot, say running at 3.5 kt to save some energy.


----------



## xort

Hey! Conky Joe Returns!!!
Can this thread be attached to the solar/wind thread?


----------



## chucklesR

I can't wait until this system gets installed on a few boats here on the Chesapeke. The endless entertainment value of listening to panic calls to Towboat U.S. for tows because the batteries are dead and a 50kt squall is coming will be priceless.

Regenerative sailing techniques won't help a bit in the light air of August on the bay around here, I forsee a lot of 'it's nine pm, no wind, no batteries and I have to get towed in' radio calls - oh no wait the batteries are drained so the VHF is useless and they have low power to the nav lights too...

Maybe Solidnav.com kicks in a BoatUS membership and Towboat U.S. unlimited towing membership as part of the 4k (plus batteries, plus solar, plus windgen, plus charging system ) cost of his system.

Solidnav, I recommend you put a outboard bracket on the back of your 27 foot Catalina test boat and hang a simple 5hp outboard with 5 gallons of that nasty oil based stuff; total weight 120 pounds, total motor time, 9 hours, total range about 40 miles, total cost about 2k. Bump that up to a 9.9 Yamaha and it'll actually charge the batteries at 8amp for you.

Buck up dude, it's only ridicule because real life gets in the way of perceptions. It's just not ready for prime time yet. And yes, I know of the cruising catamarans using hybrid and pure electric drives. Consensus is they are overpriced, underpowered, and break down too often.


----------



## camaraderie

Rockter said:


> The system in the top video is not a diesel-electric.
> 
> It is an electric motor running off batteries.
> 
> How far will it take my ship?... 11 tonf, double ender, long keel with cutaway forefoot, say running at 3.5 kt to save some energy.


Rock...obviously you are not a real sailor or you would not ask such a question. If you actually NEED an engine, you are not a good candidate for an electric/battery/passive system. Buy a trawler and admit you are not a sailor. Those real sailors who do not actually need an engine are the target market for electric engines.


----------



## engele

chucklesR said:


> Consensus is they are overpriced, underpowered, and break down too often.


Where are you getting your consensus? I haven't found any consensus on this topic at all (this thread is a good example).


----------



## Giulietta

camaraderie said:


> Those real sailors who do not actually need an engine are the target market for electric engines.


But it can't be done on my boat...unfortunately...I would love the weight reduction


----------



## engele

*Nice Boat*

Giu,

Your boat is breathtaking. There is another thread on Sailing Anarchy that discusses electric propulsion, and the possibility for _retractable_ electric propulsion. You might find it interesting. All just talk at this point. But I like intelligent dialog. There is potential there that the thread will get better too.

Retractable would be very cool on a boat like yours. Very low drag, light weight, etc.

For longer trips/races you could add battery capacity, but for around the bay type sailing leave her light. Anyhow, I can't wait to see where this technology goes. For the right applications there are a lot of options right now.

Take a look at the "echo drive II" post on SA,

-EE


----------



## engele

*Custom Saildrive Power*

Giu,

You might also consider using your saildrive as your reduction gear, and mounting an electric motor up to it directly. You still do not lose your saildrive totally, but it would allow you to try some new things. I don't know if anyone has ever done that, or if the saildrives are efficient enough to really work that way, but as a concept it is sort of neat.

You wouldn't need to buy much of anything other than a motor and controller to try it out. Your boat is definitely the type of lightweight fast boat that would benefit from electric.

I do see a benefit to cruisers as well though, despite the fact that many ridicule the idea on this forum. If your goal is in and out of port, and you're cruising for days on end without running your engine, that means you have time to recover power in between trips in and out of the harbor.

Your charge capacity does not have to be as good or as fast as your use, if you use your engine significantly less than you sail. In theory that means that a cruiser could avoid issues like polished fuel abroad entirely.

Also for those in the more remote places in latin america africa and asia, you wouldn't need to hike to a fuel station to get fuel.

There are downsides, but I think that there are a lot of upsides that are not being addressed here.

I guess to each his own, but I see this as an inevitable next step in sail propulsion. it may not be perfect now, but very soon these issues will work themselves out.

In the meantime most of the technology works well enough for my use and the upsides outweigh the downsides.

Personally I have sailed on a lot of older boats with old diesels and Atomic Four gas engines, and am no longer enamored with the mechanics.

I have also been on boats that had the diesels flooded with salt water from the exhaust causing massive damage (that happened to my Perkins with the previous owner of my boat).

So it isn't as though mechanical-oil-burning engines do not have thier own downsides as well.

Anyhow, my thoughts got waaaaay off track here, but maybe they are shared by someone out there,

-EE


----------



## engele

*Electric saildrive*

Giu,

Check out the Krautler saildrive. Maybe it would bolt up easily? There is one supposedly that uses the volvo leg.

-EE


----------



## NavySailor

*battery tech*

Different scale makes the point nearly moot, but my old hobby was Remote Control helicopters. Very near this exact "conversation" took place, the gas burners vs the electric hopefuls. The gas burners were right then, but 2 years later a battery fully functional heli was mass marketed. Then the argument was "you'll never get acrobatic with a heavy under powered electric"... Search "Mikado Logo 10 3D Electric Helicopter" on google video (no post count to post links)... The same manuevers that win acrobatic heli meets, only a little less crisp due to power to weight ratio, but he is still being quite acrobatic with that bird. Most times with technology its less a matter of if, and more a matter of when.

On a nautical note, my 'favorite' 104,000 ton vessel uses electric power... wait, does nuclear reactors tied steam turbine count as electric?

Guess naut.


----------



## engele

NavySailor said:


> Different scale makes the point nearly moot, but my old hobby was Remote Control helicopters. Very near this exact "conversation" took place, the gas burners vs the electric hopefuls. The gas burners were right then, but 2 years later a battery fully functional heli was mass marketed. Then the argument was "you'll never get acrobatic with a heavy under powered electric"... Search "Mikado Logo 10 3D Electric Helicopter" on google video (no post count to post links)... The same manuevers that win acrobatic heli meets, only a little less crisp due to power to weight ratio, but he is still being quite acrobatic with that bird. Most times with technology its less a matter of if, and more a matter of when.
> 
> On a nautical note, my 'favorite' 104,000 ton vessel uses electric power... wait, does nuclear reactors tied steam turbine count as electric?
> 
> Guess naut.


Nice point. I think that this is something that has been on the minds of pretty much every electric-interested sailor. I see it the same way. Motor technology also isn't the problem, so installing electric and modifying your storage as necessary is a real option.


----------



## Giulietta

NavySailor said:


> Different scale makes the point nearly moot, but my old hobby was Remote Control helicopters. Very near this exact "conversation" took place, the gas burners vs the electric hopefuls. The gas burners were right then, but 2 years later a battery fully functional heli was mass marketed. Then the argument was "you'll never get acrobatic with a heavy under powered electric"... Search "Mikado Logo 10 3D Electric Helicopter" on google video (no post count to post links)... The same manuevers that win acrobatic heli meets, only a little less crisp due to power to weight ratio, but he is still being quite acrobatic with that bird. Most times with technology its less a matter of if, and more a matter of when.


I see your point...but I allways get pissed off because all I get is 10 to 15 minutes flights, using 3 or 4 just to trim as you know....

my Eco8


----------



## Giulietta

Engele, thanks for the tips and time..

I had seen the one on SA before. But thanks..for me it's still a no go, yet....maybe as it gets better...where I sail, the engine needs to be a high reliabilty thing, we get hit hard sometimes...


----------



## NavySailor

Giulietta said:


> I see your point...but I allways get pissed off because all I get is 10 to 15 minutes flights, using 3 or 4 just to trim as you know....
> 
> my Eco8
> -
> 
> Nice bird! I flew Axe CP a while back. Entery level but I did upgrades to it and it ended up being a decent bird.
> 
> Yar battery life could be better, but on the other hand, have a couple of packs, swap them out... and you don't have to worry about spilling fuel on your muffler and setting your bird on fire, seen that happen a few times.


----------



## Giulietta

I do have several packs..but gets old after a while...

I do like the sound of electrical on spooling though....vft vft vft vft vft


----------



## NavySailor

Electrics do sound much more like a jet ranger than a weed-eater.


----------



## Giulietta

Man...I had so many videos of my Eco in my old laptop, you'd go crazy..all lost...oh well


----------



## engele

Giu

Yes indeed, I can understand that. I have a much slower boat than you and different needs. At 16500 lbs I have a 40 horse diesel, which is a bit much, for the weight I can pack in a LOT of batteries, all below the waterline, and be about on par (weight wise). Unfortunately my boat isn't going to win any races (as is or otherwise), but for a young guy with a first boat, I am quite happy with it. Doing something like an electric conversion would give me something fun to do. I think I would enjoy having something new.

I also am competent when it comes to working on the diesel (I've torn down the one I have), but I just don't enjoy that as much. Not to mention electric conversions are becoming more popular out here in the Western United States and the knowledge base is growing as far as what is available.

Anyhow, it was pleasant talking with you on this, and good luck with your boat into the future. I hope something falls your way that catches your attention. She is a good showcase for any technology,

-EE


----------



## engele

*Saildrive option*

Here is a PDF for electric saildrives:

Board Message


----------



## chucklesR

engele,
Consensus is the world at large.
You are aware that Sailnet has a requirement that you disclose your involvement in the marine industry? Why have you not done so?
Be advised that we can trace you  
I advise you to disclose your connections immediately, or we (the members of sailnet who can spell internet connection) will.
24 hours, just because I'm lazy.


----------



## sailaway21

Jody,
I told ya somebody was on the case. Rust never sleeps and all that.

While we await the revelation of who is actually behind door number three; has it struck anyone else here that the proponents of this nascent technology have been rather thinly spread when it come to revealing of the details on the efficacy of their contraptions? There seems to be a preponderance of posts attempting to refute the nay-sayers by means of yelling, yes it can, and little else. Where's the beef?


----------



## artbyjody

Actually Sway - I hate waiting 24 hours:

Engineered Electric Controls Ltd. - Teco-Westinghouse Motors

This may explain the rather robust attempt at bringing in his partner into this. Coincidence or not? I really hate it when a user name that has no particular nautical, or common connotation - is used that actually makes sleuthing easy. Company name is Engele...And therefore it is my consensus that he represents that one and the same. But could be wrong there was an Art Engele that puts out the racing newsletters in Monetery, CA...


----------



## ChicagoNewport27

Reading his blog on the Nada project, Nigel Calder seems to be really interested in new electric propulsion technologies.

Blog - Background


----------



## sailaway21

ChicagoNewport27 said:


> Reading his blog on the Nada project, Nigel Calder seems to be really interested in new electric propulsion technologies.
> 
> Blog - Background


HeeHee,
If you read my blog you'll find out I'm real interested in Raquel Welch. All in all, I'll leave the engine room fantasy to Nigel while I pursue other impossibilities.


----------



## denby

Anyone attacking our moderators and Sailnet members, especially well established members is out in my book. We have a very good group of members hear with a vast knowledge base and when they state facts I for one tend to listen to them. When Cam, Chuck, Sway and the likes question some one like 
SolidNav and engele and get the answers we got, then I smell something fishy.


When I say something fishy I don't mean my Portuguese buddy.


----------



## TSOJOURNER

> has it struck anyone else here that the proponents of this nascent technology have been rather thinly spread when it come to revealing of the details on the efficacy of their contraptions?


The systems do work. They are quiet, don't vibrate like a diesel and are much less harsh on the environment. If you do a bit of digging, you'll find quite a few craft that rely on electric engines as their sole means of propulsion. I think that if we took all of the home-built, the experimental and the commercially-built units together, we'd find there are a couple of thousand electric boats out there.

The problem is the energy storage system. I think that the interest in the field is growing quickly, and with the price of oil being what it is, a lot of very good research is going to be done in this are over the next decade.

I'm thinking we'll all be using electric in fifteen years.


----------



## camaraderie

First let me say that I have absolutely nothing against electric engines. I believe we are on the brink of really advanced battery and charging technology that may make a DIESEL/Electric hybrid quite practical and MORE EFFICIENT than a conventional diesel alone...especially where one can charge dockside all week long. Right now...a lot of this stuff is in the experimental stage as with Calders new boat...and quite expensive, but it should get reasonable over time.

What this "argument" has been about is the practicality of a battery only electric boat with all ENGINE power needs coming from passive sources like solar, wind vanes and regenerative prop power when under sail. 
This is what I have called "smoke and mirrors" since we all know the amp hours required to drive a the equivalent of a typical cruising boat engine HP at near hull speed even for an hour or two in flat water, far exceed the capacity of any regenerative system to replace it. Indeed, most of us spend thousands of $$'s on our cruising boats on passive systems that take up every square inch of available space just to generate a couple of hundred amp hours a day for our house bank needs.

Despite the lack of ANY real facts by our recent commercial guest...we do have a wonderful resource on this subject in Nigel Calder who has written a series of three long articles in Boat Builder magazine starting in June of 2007 which goes into far more detail and presents many more facts bout electric options, costs, efficiency etc.. These articles are quite technical in nature so if you're not up for the detail...skip to the third article and take his conclusions on faith!  If I may summarize...there is great hope for diesel electric systems but lots more work needs to be done and his new boat is being outfitted to REALLY test the various concepts out.

Couple these articles with his more recent one cited elsewhere on battery technology (that he will also install in his boat) and we will certainly have some good data to discuss in the next year or two. Here's the link to the first Boatbuilder article "hybrid marine power", the others are in subsequent months which can be accessed through the archive tabs.
Professional BoatBuilder - June/July 2007

A happy byproduct of this reading will be the discovery that one has several choices of solid, reliable and established companies with a demonstrated concern for their customers to choose from as this field develops !


----------



## camaraderie

Just came up with some data from the BENETEAU Lagoon 42 hybrid electric catamaran's user manual that makes it really clear about the power required and cruising distance achievable under battery ONLY power:
(highlighting is mine!)

* 5) BATTERY AUTONOMY*
• Battery autonomy when operating under battery power alone is based on an
average motoring speed of *4.5 knots with less than 5 knots of wind* (after all, it is a
sailing catamaran&#8230;.)
• Battery bank discharge from *100% to 80% will occur in approximately 2 hours.*
• If the generator is intentionally prevented (manual cut-off) during its attempt to
automatically start and charge at the 80% level :
• *Discharge from 80% to 60% will occur in approximately 1 hour.*
• *This means a total of 3 hours of range on the battery banks at 4.5 knots, knowing
that battery damage may begin to occur after the first 2 hours.*
• At 60% charge level, the generator will again automatically start to protect the
batteries. If one tries to turn it off, it will remain running until the batteries are
charged. The only way to stop it is to manually cut the genset battery switch in the aft
starboard cabin to force it to stop.
THEREFORE
•*To maintain optimal battery capacity, it is advised not to navigate under
battery power alone for a distance of more than 9 miles*, which is considered
enough of a margin to get to a harbor and perform docking manoeuvers.
• *Above the 13,5 mile range : risk of irreversible battery damage.
*****************

*There we have it. Now you may ask...how many batteries does it take to go this 9 miles (in flat seas and if the wind isn't blowing and the waves aren't waving)...and you may ask how big they are and what they weigh:

The answer is *TWELVE 8D's*...a mere *2500 amp hours*...a mere *2000 lbs* of batteries which you can't drain to the usual 50% capacity due to the heavy current draw. 
I am NOT disparaging these boats since they come with a generator (11kw) that kicks in and powers you as long as the DIESEL holds out...It does go to show the folly of the proponents of "passive" recharge systems without a diesel. This boat in 2 hours at 1/2 hull speed in flat water uses 500 amp hours...1000 if you push it to 3 hours!! Your gonna need a fleet of CD's Catalinas just to keep the mother ship juiced up!! 

Oh yeah...BTW...top speed with these electric engines running full out is 5.9 knots which is one of the ways they keep the POWER use down compared to the standard diesels which will drive the boat at 8 knots for several hundred miles compared to the electric model.


----------



## chucklesR

Thanks Cam,
I alluded to the hybrid catamaran's not being ready for prime time, but could not find the posted data to prove it.

Diesel electric as hybrid's are also, IMHO pointless.
Here we have all the weight and expense of 12 8D batteries, cables, a couple tons of acid and lead - and still have a diesel genset (at 11KW that's bigger than some folks diesel) with it's fuel, tankage, hoses etc.

Make sense to anyone? 

Nice research and experimentation boat, I'm not paying for that, or maintaining all that.


----------



## camaraderie

Chuck..I agree on being not ready for prime time...yet. 
But think about the new battery technology that is coming. In the example above, we need 2500 amp hours of capacity to be able to withdraw 500 amp hours safely. 
Now suppose there was a a battery that you could drain to ZERO safely and charge back to full 100 capacity in less than an hour and got 1000's of cycles instead of hundreds. You could reduce the size of the battery bank to 500 amp hours...2 8D's...to get the same performance. That is what is on the horizon. The key issue once this type of battery comes to market will be how to charge it efficiently with sufficient DC current to take advantage of its' properties. Calders boat will at least give us some data on this issue as he is planning to go with Odysseys which can be charged at 5-6x their rated capacity but do not have the exceptionally low discharge properties of the next generation battery.


----------



## engele

*Why the personal attack?*



denby said:


> When Cam, Chuck, Sway and the likes question some one like SolidNav and engele and get the answers we got, then I smell something fishy.
> 
> When I say something fishy I don't mean my Portuguese buddy.


I take that personally. I have not attacked anyone. On top of that, I have attempted to give a perspective that I found lacking.

Sailnet doesn't seam to be a good forum for design discussion. Especially when it falls to this. Be civil. Don't attack me because I disagree with the moderator on whether something is useful.

Groupthink sucks.


----------



## engele

*This was useful*



camaraderie said:


> Just came up with some data from the BENETEAU Lagoon 42 hybrid electric catamaran's user manual that makes it really clear about the power required and cruising distance achievable under battery ONLY power:
> (highlighting is mine!)
> 
> * 5) BATTERY AUTONOMY*
> • Battery autonomy when operating under battery power alone is based on an
> average motoring speed of *4.5 knots with less than 5 knots of wind* (after all, it is a
> sailing catamaran&#8230;.)
> • Battery bank discharge from *100% to 80% will occur in approximately 2 hours.*
> • If the generator is intentionally prevented (manual cut-off) during its attempt to
> automatically start and charge at the 80% level :
> • *Discharge from 80% to 60% will occur in approximately 1 hour.*
> • *This means a total of 3 hours of range on the battery banks at 4.5 knots, knowing
> that battery damage may begin to occur after the first 2 hours.*
> • At 60% charge level, the generator will again automatically start to protect the
> batteries. If one tries to turn it off, it will remain running until the batteries are
> charged. The only way to stop it is to manually cut the genset battery switch in the aft
> starboard cabin to force it to stop.
> THEREFORE
> •*To maintain optimal battery capacity, it is advised not to navigate under
> battery power alone for a distance of more than 9 miles*, which is considered
> enough of a margin to get to a harbor and perform docking manoeuvers.
> • *Above the 13,5 mile range : risk of irreversible battery damage.
> *****************
> 
> *There we have it. Now you may ask...how many batteries does it take to go this 9 miles (in flat seas and if the wind isn't blowing and the waves aren't waving)...and you may ask how big they are and what they weigh:
> 
> The answer is *TWELVE 8D's*...a mere *2500 amp hours*...a mere *2000 lbs* of batteries which you can't drain to the usual 50% capacity due to the heavy current draw.
> I am NOT disparaging these boats since they come with a generator (11kw) that kicks in and powers you as long as the DIESEL holds out...It does go to show the folly of the proponents of "passive" recharge systems without a diesel. This boat in 2 hours at 1/2 hull speed in flat water uses 500 amp hours...1000 if you push it to 3 hours!! Your gonna need a fleet of CD's Catalinas just to keep the mother ship juiced up!!
> 
> Oh yeah...BTW...top speed with these electric engines running full out is 5.9 knots which is one of the ways they keep the POWER use down compared to the standard diesels which will drive the boat at 8 knots for several hundred miles compared to the electric model.


That was actually worth reading, not definitive, but at least not out of tin air.


----------



## chucklesR

Engele, 
You haven't attacked anyone. Solidnav's President has. 

It seems to us (me for sure) you are related to solidnav - your only posts here have been to hype it's product. It gets heated because in response to questions regarding technical and practical feasibility you have responded with perception rather than fact.

One quick question, think hard on the answer - are you in any way working for or invovled with the marine industry, and in specific the company or products being sold by solidnav.com.?


----------



## engele

*yep*



Sailormann said:


> The systems do work. They are quiet, don't vibrate like a diesel and are much less harsh on the environment. If you do a bit of digging, you'll find quite a few craft that rely on electric engines as their sole means of propulsion. I think that if we took all of the home-built, the experimental and the commercially-built units together, we'd find there are a couple of thousand electric boats out there.
> 
> The problem is the energy storage system. I think that the interest in the field is growing quickly, and with the price of oil being what it is, a lot of very good research is going to be done in this are over the next decade.
> 
> I'm thinking we'll all be using electric in fifteen years.


Yes. I agree. Thank you, no one seams to pay attention to anyone else. They may not be perfect, but storage tech is changing daily.


----------



## camaraderie

I agree Engele...you have not attacked me (unlike your buddy) and vigorous debate is healthy. But I don't see any attack on YOU either...What I see are members questioning your relationship with solidnav and if you have any PERSONAL financial interest in seeing electric boats become widespread. They are suspicious because you show up talking about electric and your friends company and despite being a member since 2006, you have ONLY posted on this single subject and only within the last few days. There is NO problem if you have commercial interest...but the rules here require you to disclose. So...what's the story?


----------



## chucklesR

engele said:


> That was actually worth reading, not definitive, but at least not out of tin air.


It was and is definitive. I alluded to it my previous posts in this thread. You say you have done research on this but failed to find any of it? Your research must have began and ended at Solidnav.com

Bendytoy's literature on the Lagoon 42 has this info publically available.

As to definitiveness:

3 hours of motor at half hull speed is a fact, and as a fact that is not enough to provide a normal and necessary safety factor for any but the most short sighted fair weather sailor.

Battery driven, regenerative charged, solar charged and wind charged pure electric systems are not technically feasible or economically prudent for long range cruising as done by the majority of real people out there. Sure it's been done, by daredevil technology demostrators off on their newest publicity seeking adventures, not by your average Joe and Jane.

Sailnet is a great place to talk sailing and facts, perceptions and such are probably better at SA or latts and atts.


----------



## engele

*It interests me*

It's a subject that interests me. I have no financial interest in any sailing product of any kind, as much as I like sailing and wish I could be paid for it, I work in finance.

I joined sailnet to use the lists feature, and have browsed the forums for years. I think I'll stick to the lists.

I also have _not_ claimed to be an authority on this subject at all. I have talked to people who have done it, including an all electric Catamaran and a few monohulls, but never to anyone who used a commercial off the shelf system.

I never advocated any particular product either by the way. My posts don't advertise for anyone. Electric has worked for the people I have talked to.

One of the reasons you might find people post for the first time is when they don't find information existing in the forums. I am considering the pitfalls and whether they are worth it. I think they are.

Aside from all of that, this whole thing seams a bit childish. It isn't what I was looking for, and I wasn't looking for an all pro-electric discussion either.

Anyhow there is no point in arguing over this anymore.


----------



## engele

camaraderie said:


> I agree Engele...you have not attacked me (unlike your buddy) and vigorous debate is healthy. But I don't see any attack on YOU either...What I see are members questioning your relationship with solidnav and if you have any PERSONAL financial interest in seeing electric boats become widespread. They are suspicious because you show up talking about electric and your friends company and despite being a member since 2006, you have ONLY posted on this single subject and only within the last few days. There is NO problem if you have commercial interest...but the rules here require you to disclose. So...what's the story?


I don't have a commercial interest. I've met the owner of Solidnav, talked over beer about sailing, and like the idea of electric boats. By the way I did disclose that. I actually would like to see more of them out there, not for commercial reasons, but because I want to technology to move along more quickly and the best way for that to happen is to create demand.

I will probably go this route with a really nice diesel genset onboard. That aside, I am not sure I get the antagonism on the site.

It doesn't encourage people to post for the first time.


----------



## knothead

camaraderie said:


> There is NO problem if you have commercial interest...but the rules here require you to disclose.


Uh Oh. I think I'm in trouble. Where does one disclose their commercial interests? 
If I repent and and subject myself to self flagellation can I be forgiven?


----------



## camaraderie

Knot...we know you're a rigger...the problem comes when someone tries to hide what they are and then make comments to enhance their personal business. Not that you have ever done so...but if for any reason you decide to take that stance...then simply post your affiliation in your signature.

Thank for the response Engele...I accept your explanation. You might wanna read and understand those Nigel Calder articles I cited above before you make any re-powering decisions. Check out the coming battery technology as well before you lay in a lead mine. 
Firefly Technology - fireflyenergy.com


----------



## jgaddis

Nordhavn did a nice project with the diesel-electric propulsion. For the owner of the boat, he like the security knowing that he could lose one, or both of his main engines, and still run off his generator, 3 prime movers to keep the electric motors turning (system would also run off the battery bank for about 4 hours, the owner said it was his favorite trick to pull up to the docks silent)

On larger sail boat, running both a main engine and a genarator, couldnt this type system be used, to give you a fail safe if one engine fails?


----------



## engele

jgaddis said:


> Nordhavn did a nice project with the diesel-electric propulsion. For the owner of the boat, he like the security knowing that he could lose one, or both of his main engines, and still run off his generator, 3 prime movers to keep the electric motors turning (system would also run off the battery bank for about 4 hours, the owner said it was his favorite trick to pull up to the docks silent)
> 
> On larger sail boat, running both a main engine and a genarator, couldnt this type system be used, to give you a fail safe if one engine fails?


Yes, it could. The Nordhavn of course has room for a larger capacity of batteries though. That is a good example.

This type of configuration allows for the best of both worlds, though I've never actually been on a sailboat that was a hybrid like that.


----------



## engele

camaraderie said:


> Knot...we know you're a rigger...the problem comes when someone tries to hide what they are and then make comments to enhance their personal business. Not that you have ever done so...but if for any reason you decide to take that stance...then simply post your affiliation in your signature.
> 
> Thank for the response Engele...I accept your explanation. You might wanna read and understand those Nigel Calder articles I cited above before you make any re-powering decisions. Check out the coming battery technology as well before you lay in a lead mine.
> Firefly Technology - fireflyenergy.com


Yes battery technology is changing very quickly. Also on the horizon (supposedly) is capacitor based storage, though that may just be vaporware.

F1 racing is moving to a hybrid setup that is totally different from what we are used to as well, storing mechanical energy instead of electricity. Not helpful for sailing, but it does show that bright minds are working on the problem.

I expect both battery and fuel cell technology to get a lot cheaper in the next few years. The cost of producing solar energy has gone down significantly in the past few years as companies have moved towards using different materials to produce the cells. Hopefully we as consumers will get the benefit in a price break soon.

Storage is changing daily, but the motor technology is the same as it was fifty years ago, which is exactly why I am not afraid of a project like this.

My storage would be the last thing I would buy, and I would buy it as I experimented rather than trying to calculate my max use.

It's tough to say what a boat will use as far as fuel consumption on a regular boat with different props etc available, much less an exotic system like we are talking about here.

That isn't to say those concerns don't need to be addressed, but I don't really see a standard metric that will work across boat types to calculate what you would need to push it.

My guess is that a light Cat makes a lot of sense for these systems, but that isn't what I own.

I am still leaning in this direction.


----------



## knothead

camaraderie said:


> Knot...we know you're a rigger...the problem comes when someone tries to hide what they are and then make comments to enhance their personal business. Not that you have ever done so...but if for any reason you decide to take that stance...then simply post your affiliation in your signature.


Thanks Cam. I probably won't take that stance but with the economy the way it is I may resort to anything to drum up business. I'm not proud.


----------



## engele

chucklesR said:


> It was and is definitive. I alluded to it my previous posts in this thread. You say you have done research on this but failed to find any of it? Your research must have began and ended at Solidnav.com
> 
> Bendytoy's literature on the Lagoon 42 has this info publically available.
> 
> As to definitiveness:
> 
> 3 hours of motor at half hull speed is a fact, and as a fact that is not enough to provide a normal and necessary safety factor for any but the most short sighted fair weather sailor.
> 
> Battery driven, regenerative charged, solar charged and wind charged pure electric systems are not technically feasible or economically prudent for long range cruising as done by the majority of real people out there. Sure it's been done, by daredevil technology demostrators off on their newest publicity seeking adventures, not by your average Joe and Jane.
> 
> Sailnet is a great place to talk sailing and facts, perceptions and such are probably better at SA or latts and atts.


Not to prolong something that should have died posts ago, but a system that includes a genset makes much better range than 3 hours.

As others have pointed out, there are reputable yacht manufacturers who are using electric diesel systems. The Nordhavns (though not a sailboat) and Lagoons are just a few examples.

I read an article about the Nordhavn, but I can't recall if they are actually selling a system like that or not. I pay more attention to sailboats.


----------



## artbyjody

Engele - Do you actually own a sailboat? 


I notice every chance you get you get post on something electric motor related. Personally, while CAM here accepted your explanation - I have not. You can call it childish as you did in the neg rep you gave me - but the fact is, some of us are quite attuned to blatant methods of drumming up business etc. Your initial posts, and honestly - all of you posts have been devoid of any real substantial info - yet you criticize every one blanketed as stating we have short narrow minded views.

If I was you and this Solidnav gent is more than your "had a beer friend" - it would be more worthwhile that maybe he GIVE YOU that freebie he so boldly stated he would give to someone on Sailnet (looking out for you) - but then again you probably need a sailboat to take advantage of that if you do not have one already. But at least then you could speak from experience either way. Or maybe you know better...

However, spoiled fish smells like spoiled fish and since post #1 - this whole thread reaks of "Any press is good press" promotion.


----------



## brak

I bet that solidnav and engele are the same person. He did play a good cop bad cop thing there. However writing style, as well as simultaneous and almost word-for-word admiration of Giu's boat (not that there is anything wrong with that), as well as simply many many years of experience with various web communication mediums, among other things make me believe they are the same person. 

Not that it matters, really - just my personal opinion.


----------



## Giulietta

brak said:


> simultaneous and almost word-for-word admiration of Giu's boat


The man/men have good taste..what can you do....   

I don't blame them for liking "that" boat so much...heck...even I like it so much....


----------



## camaraderie

Jody...Brak...Pls. cut it out. Engele and solidnav are not the same person. I know exactly who they are and I accept the "good friends" explanation. They both have boats. Solid attacked me and I have handled that and he has not been back. In any event, he will pay a long term price for his temper as the internet does not "expire". Engele has attacked no one and is entitled to his opinion as is anyone here. (However wrong it may be!)
Kindly respond to the information in his posts or ignore him...but let's stop the challenges and suspicion OK?


----------



## artbyjody

camaraderie said:


> Jody...Brak...Pls. cut it out. Engele and solidnav are not the same person. I know exactly who they are and I accept the "good friends" explanation. They both have boats. Solid attacked me and I have handled that and he has not been back. In any event, he will pay a long term price for his temper as the internet does not "expire". Engele has attacked no one and is entitled to his opinion as is anyone here. (However wrong it may be!)
> Kindly respond to the information in his posts or ignore him...but let's stop the challenges and suspicion OK?


I will stop posting them - but frankly he attacked me with his neg rep to me, and upon further introspection the obvious "any way to drum up press" routine - which frankly I , less the fact for reasons you stated - normally you or others would of ended this thread three posts before January.

But I'll just put the individual on ignore - I think I know how to do that...


----------



## denby

Anyone attacking our moderators and Sailnet members, especially well established members is out in my book. We have a very good group of members hear with a vast knowledge base and when they state facts I for one tend to listen to them. *When Cam, Chuck, Sway and the likes question some one like
SolidNav and engele and get the answers we got, then I smell something fishy.*



engele said:


> I take that personally. I have not attacked anyone. On top of that, I have attempted to give a perspective that I found lacking.
> 
> Sailnet doesn't seam to be a good forum for design discussion. Especially when it falls to this. Be civil. Don't attack me because I disagree with the moderator on whether something is useful.
> 
> Groupthink sucks.


I'm sorry but I fail to see where I said you attacked any one. When I said anyone in my first line I did not signal you out, it was used in general. And where I did use your name it was referring to the answers we where getting.

But if you did take it personally please accept my apology.


----------



## brak

No problem  I also know who they are now, and I take back my statement about them being the same person.

After a bit of research I finally found what this system is made of (and a bit more information about it). This was a useful exercise for me and I will keep the motor manufacturer in mind. 

That said, I agree that this discussion had turned non-productive, my apologies for contributing to that. I'll go discuss marina blues now


----------



## camaraderie

Thanks guys...Jody...I gave you some Luvvvvv...to make up for the pain!!  Couldn't give Brak any...he's already my luhv bunny!


----------



## artbyjody

camaraderie said:


> Thanks guys...Jody...I gave you some Luvvvvv...to make up for the pain!!  Couldn't give Brak any...he's already my luhv bunny!


Stop it CAM you are embarrassing me ! Thanx


----------



## denby

camaraderie said:


> Thanks guys...Jody...I gave you some Luvvvvv...to make up for the pain!!  Couldn't give Brak any...he's already my luhv bunny!


Cam,

Have you been hanging out with Hawg again?


----------



## brak

Uh-oh. Even my wife won't call me a bunny


----------



## camaraderie

Den...Is he talking out of school again??!!


----------



## denby

camaraderie said:


> Den...Is he talking out of school again??!!


Yes he has.


----------



## chucklesR

Engele,
My apologies - we've been burned before by vendors touting numbers (see the solar stick thread) that do not up to reality who essentially pulled a 'solidnav' on us (got down right abusive when questioned).

You mentioned using this system on a light Cat. I happen to have one, a 2007 Gemini 105Mc, with 1000 on the water a good representative. They are built specifically for cruising couples and are CE open ocean category A rated.

I think it still comes down to the numbers. 
On my weight sensitive Gemini it just doesn't work; on a full keel mono where sailing performance and safety would not as deeply be affected it might.

I have a 27hp Westerbeke 30B, delivers at worst 20hp to the prop, a 15x12. Note the prop is exactly the type of high pitch prop touted as best for the system, and on my boat I have a Stillete drive leg that allows me to lift it out of the water for sailing speed; doing so adds 1 knt to my speed. 
At 2800 rpm (it maxes at 3600) I get 7.2 knts in flat water, no wind using 1.12 gals per hour. I know this because I keep logs.

Completely ignoring the battery storage issues because batteries available today are simply not comparable (nor close to being) to diesel - let's just say batteries don't matter and go on with the discussion.

20hp = 14.9kw - plain and simple (nice conversion web site so I won't bore you with the math); Unit Converter
For the purist: Horse power (hp) ---> Kilowatts (kW): hp x 0.7457 = kW
Kilowatts (kW) ---> Horse power (hp): kW x 1.341 = hp

Reverse engineering the 8 kw system that is under development indicates it delivers 10.8 hp, at 100% efficiency. I'll bet solidnav claims it's equivelant to 50hp engines simply because the target boats for that system (34-44 ft boats) have diesels n that range.

For the math challenged, that's half my current hp, and at 9600 pounds of weight (light ship, dead empty of all tools, clothes, food, water, fuel etc, not half load) provides at best 1 hp per 1000 pounds - again, half what any modern NA recommends. 
We can talk getting off the grid and being oil independent all we want, but I'm not giving up safety so I can feel good about my carbon footprint.

If I take off the 300 pounds of my engine I rounded way up) - remove the empty tanks, hoses, filters etc - I can save 350 pounds (again, light ship, so I'm not adding in fuel weight), then add back the 90 pound 8kw engine, I still - not counting batteries - need some heavy assed copper wires to handle the amp's the motor needs. I'll be nice and say 150 pound of weight total, saving me 200 pounds of weight.

To walk away dead even in weight I have a budget of 200 pounds for batteries, solar, wind and towed generator.

As I've said before, 900 pounds sinks my boat 1 inch. My full up cruising weight (due to design characteristics i.e., shortfalls) limits me to 1800 pounds of food, clothes, diesel, water and people. That's a arbitrary limit because if I say 1800 pounds I can hope for 2200 pounds in real life.

I have two 80w kyocera solar panels that deliver about 40ah a day at 12v, or 10ah at the 48v to drive the motor. If I bumped that up to 10 panels (totally ridiculous, no where to put them) they would weigh in at 500 pounds and give me only 50ah at 48v. I could motor about 1/2 hour on that; so that's no good. I could make bare steerage (1 knt) for longer, but so what?

Hmmm, wind gen - Practical sailor did a nice review on the systems out there today. I'll use their numbers - I can expect 100ah a day at 12v in most areas. going back to ridiculous installations add one on each corner of the boat (4) and I get 100ah at 48v and again get about 1 hour of motor time.
I'm completely ignoring the batteries because I said I would just so I could point on the one glaring deficiency that still remains in this system and it's marketing:

It's still not living up to the marketing claim of powering along through the doldrums now is it?

Solidnav marketing quote:
While diesel sailors are loading their decks with jerry cans and scraping through long doldrum days, you can motor through in silent bliss. As others are limited by range, you are limited only by desire. 
end quote.

The desire to have a back up motor powered by diesel?

Sure 4 windgen's dumping directly to the motor could turn the prop and with about 2ah (at 48v) - about 1/50 of it's normal - about the same as a guy with a kayak paddle. Not silent bliss in any reasonable stretch of the imagination.

We are talking doldrums so that wind gen isn't working so well now is it? We know solar, with the boat covered in panels provides half the power, during daylight - and nothing left over to store in batteries. Does it look to be feasible yet?

Kick in the aforementioned 16 lifeline AGM's, being able to use only 1/3 of ah so I don't damage the batteries doesn't really help - I still can't make the power it takes as fast as the motor consumes it. I would in fact need the batteries to store up the power so I could run the motor at all.

Serious guys with calculators take your hands off your keyboards, I know that solar panels wired in series can dump at higher voltages and make my numbers on the low side etc. I chose to keep it simple and not break out my table of formula's and calculators.

wow, I really went on for a bit didn't I ? I hate false marketing of false hopes.

Someone please prove me wrong !


----------



## jgaddis

chucklesR said:


> Engele,
> My apologies - we've been burned before by vendors touting numbers (see the solar stick thread) that do not up to reality who essentially pulled a 'solidnav' on us (got down right abusive when questioned).
> 
> You mentioned using this system on a light Cat. I happen to have one, a 2007 Gemini 105Mc, with 1000 on the water a good representative. They are built specifically for cruising couples and are CE open ocean category A rated.
> 
> I think it still comes down to the numbers.
> On my weight sensitive Gemini it just doesn't work; on a full keel mono where sailing performance and safety would not as deeply be affected it might.
> 
> I have a 27hp Westerbeke 30B, delivers at worst 20hp to the prop, a 15x12. Note the prop is exactly the type of high pitch prop touted as best for the system, and on my boat I have a Stillete drive leg that allows me to lift it out of the water for sailing speed; doing so adds 1 knt to my speed.
> At 2800 rpm (it maxes at 3600) I get 7.2 knts in flat water, no wind using 1.12 gals per hour. I know this because I keep logs.
> 
> Completely ignoring the battery storage issues because batteries available today are simply not comparable (nor close to being) to diesel - let's just say batteries don't matter and go on with the discussion.
> 
> 20hp = 14.9kw - plain and simple (nice conversion web site so I won't bore you with the math); Unit Converter
> For the purist: Horse power (hp) ---> Kilowatts (kW): hp x 0.7457 = kW
> Kilowatts (kW) ---> Horse power (hp): kW x 1.341 = hp
> 
> Reverse engineering the 8 kw system that is under development indicates it delivers 10.8 hp, at 100% efficiency. I'll bet solidnav claims it's equivelant to 50hp engines simply because the target boats for that system (34-44 ft boats) have diesels n that range.
> 
> For the math challenged, that's half my current hp, and at 9600 pounds of weight (light ship, dead empty of all tools, clothes, food, water, fuel etc, not half load) provides at best 1 hp per 1000 pounds - again, half what any modern NA recommends.
> We can talk getting off the grid and being oil independent all we want, but I'm not giving up safety so I can feel good about my carbon footprint.
> 
> If I take off the 300 pounds of my engine I rounded way up) - remove the empty tanks, hoses, filters etc - I can save 350 pounds (again, light ship, so I'm not adding in fuel weight), then add back the 90 pound 8kw engine, I still - not counting batteries - need some heavy assed copper wires to handle the amp's the motor needs. I'll be nice and say 150 pound of weight total, saving me 200 pounds of weight.
> 
> To walk away dead even in weight I have a budget of 200 pounds for batteries, solar, wind and towed generator.
> 
> As I've said before, 900 pounds sinks my boat 1 inch. My full up cruising weight (due to design characteristics i.e., shortfalls) limits me to 1800 pounds of food, clothes, diesel, water and people. That's a arbitrary limit because if I say 1800 pounds I can hope for 2200 pounds in real life.
> 
> I have two 80w kyocera solar panels that deliver about 40ah a day at 12v, or 10ah at the 48v to drive the motor. If I bumped that up to 10 panels (totally ridiculous, no where to put them) they would weigh in at 500 pounds and give me only 50ah at 48v. I could motor about 1/2 hour on that; so that's no good. I could make bare steerage (1 knt) for longer, but so what?
> 
> Hmmm, wind gen - Practical sailor did a nice review on the systems out there today. I'll use their numbers - I can expect 100ah a day at 12v in most areas. going back to ridiculous installations add one on each corner of the boat (4) and I get 100ah at 48v and again get about 1 hour of motor time.
> I'm completely ignoring the batteries because I said I would just so I could point on the one glaring deficiency that still remains in this system and it's marketing:
> 
> It's still not living up to the marketing claim of powering along through the doldrums now is it?
> 
> Solidnav marketing quote:
> While diesel sailors are loading their decks with jerry cans and scraping through long doldrum days, you can motor through in silent bliss. As others are limited by range, you are limited only by desire.
> end quote.
> 
> The desire to have a back up motor powered by diesel?
> 
> Sure 4 windgen's dumping directly to the motor could turn the prop and with about 2ah (at 48v) - about 1/50 of it's normal - about the same as a guy with a kayak paddle. Not silent bliss in any reasonable stretch of the imagination.
> 
> We are talking doldrums so that wind gen isn't working so well now is it? We know solar, with the boat covered in panels provides half the power, during daylight - and nothing left over to store in batteries. Does it look to be feasible yet?
> 
> Kick in the aforementioned 16 lifeline AGM's, being able to use only 1/3 of ah so I don't damage the batteries doesn't really help - I still can't make the power it takes as fast as the motor consumes it. I would in fact need the batteries to store up the power so I could run the motor at all.
> 
> Serious guys with calculators take your hands off your keyboards, I know that solar panels wired in series can dump at higher voltages and make my numbers on the low side etc. I chose to keep it simple and not break out my table of formula's and calculators.
> 
> wow, I really went on for a bit didn't I ? I hate false marketing of false hopes.
> 
> Someone please prove me wrong !


That would make for one awesome gemini!!!! Do you take amex?


----------



## Lbjordal

regarding the weight issue you should have a look at some more untraditional consepts. If you have a look at the folowing sites you will see that a 7kW motor dont need to be more than 1500 grams. costing 150 dollars. Add speedcontroller and all you need is batteries.

regarding the speedcontroller you may use this one from castleCreations. It is rated at 240 amps 50 Volts. I belive you can get it for less than 400 dollars. 

This might be a nice option for those of us using the boat for daysailing, not needing anything but harbour navigation.

Sorry, couldnt post links, look up "hxt outrunner", and "castle creations hydra 240"

Lars


----------



## artbyjody

HTX 

and

CastleCreations

Neither of which I could see meeting the requirements of powering the likes of 18-25 HP - even for Daysailing.

One thing to note when thinking of these issues is the max RPMs, you can generate to move the prop. When cruising the RPMs are fairly a constant but in docking maneuvers - the amount of thrust needed - and thus electric required - are substantially variant. It goes without saying that for a fossil fuel or hybrid - that there is a constant that you can draw from. As batteries deplete so does the actual amount of energy draw one can obtain from using such. So, in matters of docking - a hard blow, swift currents, etc... One really takes the risk s of a decremental power source to provide that umpff when you need it....


----------



## Lbjordal

I am not saying that electric is superior in any way, just pointing out that what most "marine dealers" are supplying is not quite up to todays standards. 

btw, I belive that 7kw, will be sufficient for my 20 feet keelboat, wich at the time is powerd by an outboard. moving to electric power will allow me to move more weight to the centre of the boat giving it better balance and keeping the prop in the water even in rougf weather

Lars


----------



## camaraderie

Lars..Well 7kw should power even a heavy 20 footer just fine. As long as you can charge at the dock and have enough battery power to get you in and out of the harbor...electric will probably work for you. The problem comes when you want more than that. You might consider carrying something like a portable Honda generator on board for emergency charging.Welcome aboard!!


----------



## engele

artbyjody said:


> HTX
> 
> and
> 
> CastleCreations
> 
> Neither of which I could see meeting the requirements of powering the likes of 18-25 HP - even for Daysailing.
> 
> One thing to note when thinking of these issues is the max RPMs, you can generate to move the prop. When cruising the RPMs are fairly a constant but in docking maneuvers - the amount of thrust needed - and thus electric required - are substantially variant. It goes without saying that for a fossil fuel or hybrid - that there is a constant that you can draw from. As batteries deplete so does the actual amount of energy draw one can obtain from using such. So, in matters of docking - a hard blow, swift currents, etc... One really takes the risk s of a decremental power source to provide that umpff when you need it....


Docking is very different from the guys I have talked to. But it isn't worse. Your max RPMs are not the issue you are thinking of though because you have all of your torque instantly in an electric. In a diesel you need to get your rpms up to get the torque, but in an electric, as long as you have a moderate amount of power, you will have enough for short peaks.

Think of a cordless drill as the battery dies. If you wait a moment, you can get the last screw, because the drill can power up for that one last peak. It's the same concept here.

The main thing that I have heard that changes docking, is that there is no transmission and no slop between forward and reverse, if you come in and then throw it into reverse, on an electric your power is at full instantly... and in reverse. You still have boat speed, but you don't have engine bogging.


----------



## engele

chucklesR said:


> Engele,
> My apologies - we've been burned before by vendors touting numbers (see the solar stick thread) that do not up to reality who essentially pulled a 'solidnav' on us (got down right abusive when questioned).
> 
> You mentioned using this system on a light Cat. I happen to have one, a 2007 Gemini 105Mc, with 1000 on the water a good representative. They are built specifically for cruising couples and are CE open ocean category A rated.
> 
> I think it still comes down to the numbers.
> On my weight sensitive Gemini it just doesn't work; on a full keel mono where sailing performance and safety would not as deeply be affected it might.
> 
> I have a 27hp Westerbeke 30B, delivers at worst 20hp to the prop, a 15x12. Note the prop is exactly the type of high pitch prop touted as best for the system, and on my boat I have a Stillete drive leg that allows me to lift it out of the water for sailing speed; doing so adds 1 knt to my speed.
> At 2800 rpm (it maxes at 3600) I get 7.2 knts in flat water, no wind using 1.12 gals per hour. I know this because I keep logs.
> 
> Completely ignoring the battery storage issues because batteries available today are simply not comparable (nor close to being) to diesel - let's just say batteries don't matter and go on with the discussion.
> 
> 20hp = 14.9kw - plain and simple (nice conversion web site so I won't bore you with the math); Unit Converter
> For the purist: Horse power (hp) ---> Kilowatts (kW): hp x 0.7457 = kW
> Kilowatts (kW) ---> Horse power (hp): kW x 1.341 = hp
> 
> Reverse engineering the 8 kw system that is under development indicates it delivers 10.8 hp, at 100% efficiency. I'll bet solidnav claims it's equivelant to 50hp engines simply because the target boats for that system (34-44 ft boats) have diesels n that range.
> 
> For the math challenged, that's half my current hp, and at 9600 pounds of weight (light ship, dead empty of all tools, clothes, food, water, fuel etc, not half load) provides at best 1 hp per 1000 pounds - again, half what any modern NA recommends.
> We can talk getting off the grid and being oil independent all we want, but I'm not giving up safety so I can feel good about my carbon footprint.
> 
> If I take off the 300 pounds of my engine I rounded way up) - remove the empty tanks, hoses, filters etc - I can save 350 pounds (again, light ship, so I'm not adding in fuel weight), then add back the 90 pound 8kw engine, I still - not counting batteries - need some heavy assed copper wires to handle the amp's the motor needs. I'll be nice and say 150 pound of weight total, saving me 200 pounds of weight.
> 
> To walk away dead even in weight I have a budget of 200 pounds for batteries, solar, wind and towed generator.
> 
> As I've said before, 900 pounds sinks my boat 1 inch. My full up cruising weight (due to design characteristics i.e., shortfalls) limits me to 1800 pounds of food, clothes, diesel, water and people. That's a arbitrary limit because if I say 1800 pounds I can hope for 2200 pounds in real life.
> 
> I have two 80w kyocera solar panels that deliver about 40ah a day at 12v, or 10ah at the 48v to drive the motor. If I bumped that up to 10 panels (totally ridiculous, no where to put them) they would weigh in at 500 pounds and give me only 50ah at 48v. I could motor about 1/2 hour on that; so that's no good. I could make bare steerage (1 knt) for longer, but so what?
> 
> Hmmm, wind gen - Practical sailor did a nice review on the systems out there today. I'll use their numbers - I can expect 100ah a day at 12v in most areas. going back to ridiculous installations add one on each corner of the boat (4) and I get 100ah at 48v and again get about 1 hour of motor time.
> I'm completely ignoring the batteries because I said I would just so I could point on the one glaring deficiency that still remains in this system and it's marketing:
> 
> It's still not living up to the marketing claim of powering along through the doldrums now is it?
> 
> Solidnav marketing quote:
> While diesel sailors are loading their decks with jerry cans and scraping through long doldrum days, you can motor through in silent bliss. As others are limited by range, you are limited only by desire.
> end quote.
> 
> The desire to have a back up motor powered by diesel?
> 
> Sure 4 windgen's dumping directly to the motor could turn the prop and with about 2ah (at 48v) - about 1/50 of it's normal - about the same as a guy with a kayak paddle. Not silent bliss in any reasonable stretch of the imagination.
> 
> We are talking doldrums so that wind gen isn't working so well now is it? We know solar, with the boat covered in panels provides half the power, during daylight - and nothing left over to store in batteries. Does it look to be feasible yet?
> 
> Kick in the aforementioned 16 lifeline AGM's, being able to use only 1/3 of ah so I don't damage the batteries doesn't really help - I still can't make the power it takes as fast as the motor consumes it. I would in fact need the batteries to store up the power so I could run the motor at all.
> 
> Serious guys with calculators take your hands off your keyboards, I know that solar panels wired in series can dump at higher voltages and make my numbers on the low side etc. I chose to keep it simple and not break out my table of formula's and calculators.
> 
> wow, I really went on for a bit didn't I ? I hate false marketing of false hopes.
> 
> Someone please prove me wrong !


Apology accepted. And nice post.

You have a point as far as a weight sensitive boat, that needs long range motoring capability. Here is where I get my inclination to think that this can be made to work (aside from seeing some examples).

There is an electric Cat here in the marina that I've looked at often (http://www.gatoverde.com/PageID/143/default.aspx).. anyhow:

My initial thoughts on this stemmed from the range estimate on electric cars. The estimate 80-100 mile range in electric porches and such (not a lot of room for batteries). The cars also have a transmission to knock efficiency, limited carrying capacity for batteries etc. That is at least an hour of runtime at freeway speeds in a car (i.e. the motors is running at low efficiency, without all that many batteries)

Gas HP and Diesel HP are different from Diesel and Electric HP as well. Diesel has a better torque curve (the reason you see 20HP gas lawn tractors and 12 HP Diesel front end loaders).

On a lot of boats we have big diesels because we need the torque delivery, and that means that if you hit the throttle, you can cavitate the prop (if you want). Now a bit of that power is nice to have. it means that your delivery of power is quick if you need it. On the other hand, if you have a flat torque curve do you need that much power?

Back to the lawn tractor versus the loader analogy.

Using this logic (that the torque curve is so nice for this application that less power is needed) I have heard people claim that you only really need a third or less of the comparable diesel HP. It _seems_ logical.

Then you consider that it gets harder and harder to push the boat as you approach hull speed, and your efficiency drops off (in fuel or battery powered craft), you start to wonder what pushing a 7kt hull speed boat through the water at 5kts would be like (of course with the ability to peak it out at 7 if you needed).

Now consider that you can occasionally need to buck a tide or something like that. What is the longest period of time that you would ever be bucking a tide? If a car as small as a Porsche can get 100 mile range, what do you need to add to your boat to get four hours of high speed motoring? Lets say for the sake of argument that you need four times the battery capacity. My boat would have that.

If you also have a genset, to supplement your use (possibly already installed depending on the boat), you can offset your battery storage by quite a bit. Let's still say you need four times the capacity of the Porsche though.

Regen, solar, and to a lesser extent wind power just supplement your shore power, or genset (wind and the genset being the most helpful).

Now if we were on a long tack in the trades for several days with two or three wind generators, solar and regen, you could possibly bring your batteries back up to charge. Not motoring every day. Good wind, regen, solar, and not running your genset. If you ran the genset for one day out of five, and didn't motor, you could recharge your banks and have full motoring capacity.

Also most of the time we won't need to be motoring for more than a few hours, so when we do, we can get where we need to go and either run the genset, or plug into shore power to top of the banks.

Also while it might not be as comfortable as 50 gallons of diesel, solar and electric would be a lot more comfortable than an empty fuel tank in the doldrums (say your fuel gets polished).

I have paddled a big boat around in the marina when we had engine problems, so even a kayak paddle is better than nothing.

Solidnav claims they can replace up to a 24 HP diesel per their site. So far it sounds as though their market is smaller boats, and not the 34-40 footers.

The product they currently offer is not large enough to power my 38 footer.

They also use a 4kw motor, which is similar to other systems I've seen around, but less than the 8kw that your conversion site talked about for a similar sized power plant.

I am going to come back to this when I have some time to poke around and gather some more data, but this is much more in line with the discussion I was looking for. I'll see if I can find some more hard numbers,

-EE


----------



## engele

artbyjody said:


> HTX
> 
> and
> 
> CastleCreations
> 
> Neither of which I could see meeting the requirements of powering the likes of 18-25 HP - even for Daysailing.
> 
> One thing to note when thinking of these issues is the max RPMs, you can generate to move the prop. When cruising the RPMs are fairly a constant but in docking maneuvers - the amount of thrust needed - and thus electric required - are substantially variant. It goes without saying that for a fossil fuel or hybrid - that there is a constant that you can draw from. As batteries deplete so does the actual amount of energy draw one can obtain from using such. So, in matters of docking - a hard blow, swift currents, etc... One really takes the risk s of a decremental power source to provide that umpff when you need it....


I am not sure I saw what he intended on those links, but I have to agree with Jody on this, at least temporarily, not about the docking part, but I didn't see a diesel replacement on there. Were there larger than RC motors on there?


----------



## Lbjordal

No diesel replacement Engele. Just playing with the idea of putting one of the larger rc motors in my boat and wanted to know if you guys tought it possible. 

I guess we might see more hybrid boats in the near future, but pure electric wont happen anytime soon


----------



## artbyjody

engele said:


> The main thing that I have heard that changes docking, is that there is no transmission and no slop between forward and reverse, if you come in and then throw it into reverse, on an electric your power is at full instantly... and in reverse. You still have boat speed, but you don't have engine bogging.


Well since the cordless drill analogy has been used now. On a electric only system, you will get much more cavitation which doesn't translate to HP. Think of a drill when you you over extend its capabilities and the bit ends up getting bogged down. It actually drains the battery down faster as a result.

There is also the misconception of "instantaneous". The motor is still coupled to a shaft, the shaft to a prop. Torque is not the same as HP.

For example: Electric R/C - Demystifying Gearing and Gearboxes - Stefan Vorkoetter explains a lot of what the RC issues are when comes to such.

Just like using a drill, the ability to use the lowest possible RPM to get desired torque is most desirable - and at a steady constant (say actually getting out of the harbor) can be reasonably efficient. Often times (most of the time who are we kidding here) in docking that is not the case, because of issues of cavitation and the nature of currents, wind, and overall velocity of ones vessel's mass. Compare it to when a drill used in a scenario where a drill bit is pressed to hard or prop is over driven past actual prop ability to bite - more energy is lost as heat, and expended to try to overcome the forces .

This is one of the reasons hybrid cars utilize braking regen systems because so much energy is used to stop a vehicle. A boat in that context is not any different.....


----------



## chucklesR

A Gemini currently undergoing the conversion to a e-pod system, albeit with a 15hp honda o/b as backup. He expects 1-3 hours of motor time with his set up and has done the careful documentation and caluculating. 8 Odyssey PC2250 batteries is his bank, 4 on each side in place of the water tanks. He really did research the crap out of this, these batteries tolerate high dischage rates well. Money/cost did not factor into his plans, but his Westerbeke and drive leg are currently for sail.

: E-Pod 3000 Conversion

Note the pundits at the yahoo gemini group where we talk all things boating and gemini related were somewhat amazed, the owner is disregarding the designers weight recommendations (i.e., putting that weight of batteries in that section of the hull due to the design scantlings and weight distribution). Our batteries are normally mounted mid ship in the hulls, down low.

We wished him luck and look forward to his reports, the owner of this boat is one of our most progressive members in making mod's to his boat.

Basically, by his calculations ( E-Pod Weight )
He's coming up even in weight, for 1-3 hours of motor time. He left a few things off (heavy wiring etc..) but it's a damn good start.

Certainly this is not the off the grid blissful motoring through the doldrums some product purveyors would have us believe they can deliver.

One note Lars, you skipped the who issue of battery weight, the weight of a electric motor is trival in comparision to the battery components.


----------



## engele

chucklesR said:


> A Gemini currently undergoing the conversion to a e-pod system, albeit with a 15hp honda o/b as backup. He expects 1-3 hours of motor time with his set up and has done the careful documentation and caluculating. 8 Odyssey PC2250 batteries is his bank, 4 on each side in place of the water tanks. He really did research the crap out of this, these batteries tolerate high dischage rates well. Money/cost did not factor into his plans, but his Westerbeke and drive leg are currently for sail.
> 
> : E-Pod 3000 Conversion
> 
> Note the pundits at the yahoo gemini group where we talk all things boating and gemini related were somewhat amazed, the owner is disregarding the designers weight recommendations (i.e., putting that weight of batteries in that section of the hull due to the design scantlings and weight distribution). Our batteries are normally mounted mid ship in the hulls, down low.
> 
> We wished him luck and look forward to his reports, the owner of this boat is one of our most progressive members in making mod's to his boat.
> 
> Basically, by his calculations ( E-Pod Weight )
> He's coming up even in weight, for 1-3 hours of motor time. He left a few things off (heavy wiring etc..) but it's a damn good start.
> 
> Certainly this is not the off the grid blissful motoring through the doldrums some product purveyors would have us believe they can deliver.
> 
> One note Lars, you skipped the who issue of battery weight, the weight of a electric motor is trival in comparision to the battery components.


Looks like a neat setup. You are right about battery weight being probably the biggest negative (that and life of batteries if you don't get good quality).

Anyhow, I am taking off for a week to the BVI to try out a Lagoon. We'll see how she rides,

In the mean time, you all have a great week and a half,

-EE


----------



## denby

Engele,

Have a fun and safe trip.


----------



## tjaldur

At this site: Products OZmarine R&D AB one can study the electric engine designed to use with a Swede 41. (It is in English). The batteries are charged through the propeller. It takes 20 minutes of sailing in 6 knots to use the engine 5 minutes in 3 knots.

Unfortunately I cannot use an electric engine on my ship, that weights 16 ton (metric). But I use an electric trolling outboard on my dinghy. With that one I use two 80 amp battery. One in the dinghy and one aboard the ship for charging. An 80 amp battery I can comfortably lift in and out of the dinghy with one hand, while standing in the dinghy. So I just change battery when it gets flat.

One charging gives me about 4 hours in the dinghy at around 3 knots. The distance from my mooring to the two important stores in my life, food and spareparts is about one nautical mile. Thus I change battery after 4 trips to the stores.

The two main advantages with this trolling outboard are the absolute silence and not to worry about gasoline (in the dinghy). The batteries are charged through a 1500 watt inverter with a 20 amp charger (220 volts) from the batteries on-board (440 amps). Now this battery-bank on board is charged by solar panels and a windmill and in worst case by a gasoline driven 2.5 KW generator. This generator will be replaced with a dieseldriven generator, once I can afford it.


----------



## davidpm

Well it's been a month so time to stir the pot.
What if we give up on the idea, just temporarily, of green sailing and just think about plain hybrid?

Diesel genset, electric motor, standard size battery banks or maybe a little bigger than normal.
Yes it will cost more but.

Can we get better efficiency out of the diesel by running it at load all the time.
Can we get longer life out of the diesel by running it more controlled?
Can we insulate the genset easier and more effectivly then the engine?
Can we have one larger diesel instead of engine and genset?
Will we get better efficiency between the electric motor and prop.
Can we use the electric motor and prop to act a generator.
Can we take advantage of the seperation of the genset and the prop for design advantage?


I’m thinking of maybe an hours worth of battery for cruising speed.

If the extra cost can be justified this may be a platform that the green stuff can be bolted on as we figure it out.

In other words how long does your trip from the doc to where you can sail take?


----------



## negrini

Excelent point David. This is a math for efficiency and reliability. Regardless your source, it will always take same amount of power to move your boat, given same conditions. Unless they come with new materials for beter efficiency, either diesels or electrical, efficiency math will always be the same. So, why not spend more time designing beter hulls, sails, rig, watermakers, etc increasing efficiency by using less power ? Don't you think serious designers are just doing that ?


----------



## davidpm

negrini said:


> Don't you think serious designers are just doing that ?


It is possible that a hybred system may have advantages that would be useful for some people but new boat mfr's are not convinced the market is big enough.


----------



## Idiens

Two engines cost twice the price of one (rule of thumb). Hence a hybrid has got to work pretty hard to justify its installation cost. I looked into a German hybrid system before replacing my diesel. It didn't justify its cost.


----------



## sailingdog

Another point is that hybrids often have to be much heavier than the equivalent internal combustion engine. The energy density of liquid hydrocarbons is awfully tough to beat. The reliability of a simple marine diesel, which doesn't have EFI or any fancy electronics in most cases, is also pretty hard to beat.


----------



## chucklesR

davidpm said:


> Well it's been a month so time to stir the pot.
> What if we give up on the idea, just temporarily, of green sailing and just think about plain hybrid?
> 
> Diesel genset, electric motor, standard size battery banks or maybe a little bigger than normal.
> Yes it will cost more but.


I'd rather not fund the research department of corporation X, thanks very much.



> Can we get better efficiency out of the diesel by running it at load all the time.


It's a sail boat, I don't want to run a diesel all the time - but yes it would be more efficient to run a engine at load, if I WANTED TO RUN IT AT ALL.


> Can we get longer life out of the diesel by running it more controlled?
> Can we insulate the genset easier and more effectivly then the engine?


 Sure, got nothing to do with hybrid tho.



> Can we have one larger diesel instead of engine and genset?


Most sail boats only have one engine, that's why they are sailboats. The upscale market and cruisers that have a separate genset are no where near the market that current electric propulsion can handle (see dozens of posts above in this thread to prove that. These units (electric) are good for docking runs, not cruising - day sailors only need docking runs and don't have gensets onboard. Apples and oranges, day and night.



> Will we get better efficiency between the electric motor and prop.
> Can we use the electric motor and prop to act a generator.
> Can we take advantage of the seperation of the genset and the prop for design advantage?


Yes to all, electric has a torque advantage with prop design, the cost is not comparable with the benefit - i.e., it's the only, single real advantage to have a electric motor drive the prop instead of a diesel unit.
I think a real transmission (multi gear) on a diesel would be a far better option and can not for the life of me figure out why they are not in use on boats.
I can free spin a prop and use it as a generator without the hybrid add on (it's called a towed generator, works great cost 1/4 of a hybrid or less) and take advantage of the genset /prop separation without the hybrid.

Taking out the green, hybrid's aren't ready for prime time unless you are a bleeding edge gear head who doesn't mind supporting Company Y and Corporation X's research department.



> I'm thinking of maybe an hours worth of battery for cruising speed.
> 
> If the extra cost can be justified this may be a platform that the green stuff can be bolted on as we figure it out.


One hour = day sail, docking manuevering only, and competely eradicates any safety factor (lee shores, emergencies). Not on my boat, not on a boat I sail on. Extra cost I've already addressed.



> In other words how long does your trip from the doc to where you can sail take?


good question, on my dinghy about 3 seconds. That's where I will use hybrid technology called oars.
When apples = apples this will be ready for serious discussion. I mean 500 miles of cruise range, easily extended with add on power packs. I mean 20 minutes at the dock and I'm refilled and ready to go again. I mean the price is the same or ball park.

Until then it's snake oil salesman stuff to me.


----------



## Giulietta

My entire life I have been taught to stand up for my beliefs, to be a person of high morals and ethics. That's why I feel obligated to step back and consider the problem of Solidnav's objectives in the larger picture of popular culture imagery. What follows is a series of remarks addressed to the readers of this letter and to Solidnav itself. Solidnav often expresses great interest in, and approval of, violent acts reported in the press -- spousal abuse, shooting sprees, capital punishment, and so forth. We can therefore extrapolate that Solidnav refuses to come to terms with reality. It prefers instead to live in a fantasy world of rationalization and hallucination. The salient point here is that Solidnav talks a lot about neopaganism and how wonderful it is. However, it's never actually defined what it means. How can it argue for something it's never defined? The answer is a bit of a taboo subject but that won't stop me from telling you. You see, the concepts underlying Solidnav's apolaustic intimations are like the Ptolemaic astronomy, which could not have been saved by positing more epicycles or eliminating some of the more glaring discrepancies. The fundamental idea -- that the heavens revolve around the Earth -- was wrong, just as Solidnav's idea that it was chosen by God as the trustee of His wishes and desires is wrong. 

Solidnav's bromides leave me with several unanswered questions: What would its response be if someone suggested that there is little doubt that frotteurism has impaired its ability to think straight? And is it really its impression that hideous-to-the-core, loud half-wits and the most self-aggrandizing barrators I've ever seen should rule this country? These are difficult questions to answer because it wants to do exactly the things it accuses nit-picky, vexatious slackers of doing. Personally, I don't want that. Personally, I prefer freedom. If you also prefer freedom then you should be working with me to ensure that we survive and emerge triumphant out of the coming chaos and destruction. There is no place in this country where we are safe from Solidnav's helots, no place where we are not targeted for hatred and attack. 

I will never give up. I will never stop trying. And I will use every avenue possible to present another paradigm in opposition to its lawless cajoleries. As reluctant as I am to admit it, Solidnav uses highfalutin terms like "schizosaccharomycetaceae" and "homeotransplantation" to conceal its plans to eat our nation to its bones. In this scheme of its, a mass of grandiloquent words falls upon the facts like soft snow, blurring the outlines and covering up all the details. We become unable to see that I can no longer get very excited about any revelation of Solidnav's hypocrisy or crookedness. It's what I've come to expect by now. That's my story and I'm sticking to it.


----------



## Giulietta

Like the Erlking in Goethe's famous poem, the maleficence of Solidnav's morals can sometimes be imperceptible. The purpose of this letter is therefore to expose the psychotic nature of Solidnav's plaints and let you draw your own conclusions about Solidnav's motives. Let me preface my discussion by quickly reasserting a familiar theme of my previous letters: I welcome Solidnav's comments. However, Solidnav needs to realize that he and his homophobic mind games should be shunned. (Yes, materialism is correctly defined by its mealymouthed style, structure, and methods, not by its stated or apparent ideological premises or goals, but that's an entirely different story.) What do you think of this: It behooves all of us to understand that I would like to register my strong objection to his adages? Solidnav believes that all it takes to solve our social woes are shotgun marriages, heavy-handed divorce laws, and a return to some mythical 1950s Shangri-la. That's just wrong. He further believes that we have too much freedom. Wrong again! 

I once told Solidnav that money and greed shape his thinking. How did he respond to that? He proceeded to curse me off using a number of colorful expletives not befitting this letter, which serves only to show that there are three fairly obvious problems with Solidnav's ultimata, each of which needs to be addressed by any letter that attempts to present another paradigm in opposition to Solidnav's bleeding-heart complaints. First, until recently, Solidnav's ruses have gone unnoticed and unanalyzed. Second, Solidnav has studiously avoided being contaminated by the facts. And third, the last time I heard Solidnav ramble on in his characteristically bibulous blather he said something about wanting to replace our natural soul with an artificial one. I feel sorry for the human race when I hear stuff like that. I may not be perfect, but at least I'm not afraid to say that I myself will never give up. I will never stop trying. And I will use every avenue possible to acknowledge that he has been dabbling in demagogism. 

For the nonce, Solidnav is content to shame my name. But sometime soon, he will make a big deal out of nothing. That's a very important point; I will stop at nothing to improve the lot of humankind. My resolve cannot fully be articulated but it is unyielding. As evidence, consider that Solidnav fervently believes that divine ichor flows through his veins. This shows that he is not merely mistaken about one little fact among millions of facts but that Solidnav wants to drag everything that is truly great into the gutter. It gets better: He actually believes that character development is not a matter of "strength through adversity" but rather, "entitlement through victimization". I guess no one's ever told him that if we are powerless to balkanize his garrulous claque into an etiolated and sapless agglomeration, it is because we have allowed Solidnav to stonewall on issues in which taxpayers see a vital public interest. Now that you've read the bulk of this letter, it should not come as a surprise that I find it ironic that Solidnav calls me insincere when he's the most insincere person you'll ever see. However, this fact bears repeating again and again, until the words crack through the hardened exteriors of those who would marginalize and eventually even outlaw responsible critics of violent maggots. I am referring, of course, to the likes of Solidnav.


----------



## Giulietta

If you are one of the few who has never been presented with evidence that Solidnav plans to promote a herd mentality over principled, individual thought, then be glad that the task to educate yourself has just become easy. With this letter, I compile all of the necessary evidence into one easy-to-read document. The points I plan to make in this letter will sound tediously familiar to everyone who wants to convince contemptuous buffoons to stop supporting Solidnav and tolerating its grievances. Nevertheless, the space remaining in this letter will not suffice even to enumerate the ways in which it has tried to cause an increase in disease, nativism, crime, and vice. A central point of Solidnav's belief systems is the notion that Solidnav is beyond reproach. Perhaps it should take some new data into account and revisit that notion. I think it'd find that by writing this letter, I am surely sticking my head far above the parapet. The big danger is that Solidnav will retaliate against me. It'll most likely try to force me to have a conniption although another possibility is that there are many roads leading to the defeat of its plans to take over society's eyes, ears, mind, and spirit. I decidedly believe that all of these roads must eventually pass through the same set of gates: the ability to present a clear picture of what is happening, what has happened, and what is likely to happen in the future. 

The fault, dear Solidnav, is not in your stars but in yourself. Solidnav likes to compare its remonstrations to those that shaped this nation. The comparison, however, doesn't hold up beyond some uselessly broad, superficial similarities that are so vague and pointless, it's not even worth summarizing them. Solidnav dances to the tune of shiftless corporatism. Well, that's another story. To get back to my main point, I ought to mention that Solidnav's attempts to impact public policy for years to come are much worse than mere separatism. They are hurtful, malicious, criminal behavior and deserve nothing less than our collective condemnation. 

As you can see, I plan to make some changes here. Are you with me -- or against me? Whatever you decide, we can never return to the past. And if we are ever to move forward to the future, we doubtlessly have to pursue virtue and knowledge. In closing, all that I ask is that you join me to stop Solidnav and act as a positive role model for younger people.


----------



## Giulietta

There are some comments I need to make regarding Solidnav. To get right down to it, I feel that writing this letter is like celestial navigation. Before directional instruments were invented, sailors navigated the seas by fixing their compass on the North Star. However, if Solidnav were to trick them into fixing their compass on the wrong star they'd soon be so off-course that they'd actually be willing to help it sell otherwise perfectly reasonable people the idée fixe that it is forward-looking, open-minded, and creative. In order to understand the motivation behind Solidnav's imprecations it is important first to draw an accurate portrait of Solidnav's ideological alignment. Solidnav is always demanding money, sympathy, and the punishment of its critics, but I won't linger on that. We'd all be in grave danger if Solidnav continued to engage in its dysfunctional behavior. Solidnav likes to have difficult social issues presented to it in simple, black-and-white terms. Period, finis, and Q.E.D.


----------



## chucklesR

Alex, I appreciate your ability to cut and paste, but what's that got to do with electric propulsion?


----------



## artbyjody

GUI has resorted to the auto post creation, to compensate for his lack of understanding of the complexities of how solar power and celestial powerment can not actually co-exist, due the differences actually being night and day.


----------



## denby

Gui must be bored today.


----------



## engele

Wow! You leave for a little while and when you come back you can't understand a damn thing going down the board. I've set this aside for the moment (tired of the argument), but geez these forums can get crazy. Sometimes it makes you just want to sit on the sidelines (like I did for years),


----------



## bheintz

Giulietta said:


> . . . So that was my contribution here...signing off. . . .


Giu has contributed some interesting links and points of view to this thread, however I do not find #147, #148, #149, #150 to be useful.


----------



## bheintz

I get the impression that the naysayers perceive SolidNav's description of its motor as something that is pleasant to contemplate but is very unlikely to be realized.

Perhaps the current state of battery technology does not meet the needs of the cruising sailor that needs to reach a destination by a certain time/date and there will probably come a time when a combination of fuel cells and batteries and electric motors will replace internal combustion engines

The "car phone" is a good example. Car phones were in use as far back as 1935 (ex. 1954 Bogart movie called "Sabrina", 1955-65 Perry Mason) this was a two-way analog radio in use until the 70's. Then in the 80's cell towers were built and cell phones used car batteries. Now they are available in convience stores with charged batteries.

Like the original car phones, electric motors for sailboats is a good option for those who can justify their need.

The following graph is taken from Torqeedo literature comparing different battery technology:


----------



## tommays

This is OLD but let me TROLL it UP 










This is as easy as it gets to move with a 4Hp pushing it at 6K on a calm day with 5k being a cruise speed

The 1500 dollar Torqeedo with a spare 300 Wh, 29.6 V battery 600 dollar is by far the most refined product on the market 










The sum total of these properties make a Torqeedo Travel motor into the perfect drive for small boats, dinghies, tenders, jollies, and daysailors up to 1.5 tons of displacement. There is simply no competition when it comes to performance, transport and space-saving storage - both on board and on land.

BUT being in and area were the water has a nasty habit of always moving the wrong way at 1 to 2 knots at least 1/2 of my sailing time i would be pretty screwed even with the spare battery if the wind does what it does on LIS stops 

Seriously the motors they claim are equal in thrust to my 4hp seem to be able to move the boat about 3 miles at 3 to 4 K with the 300 Wh battery

I would have to go with a 24 volt on board battery bank which makes being able to carry the battery packs home to charge a no go solution


----------



## bheintz

Rockter said:


> There is no way on this earth, with earthly laws of physics, that a fuel-driven electric generator, feeding mechanical energy to a generator, then electrical energy to a motor, and from there mechanical energy to a prop will EVER out-perform the direct drive-to-prop diesel in the first place. There is just no way that can happen.
> 
> What am I missing here?
> 
> If you want something quiet to get you in and out of harbour, then perhaps, but this stuff must not be advertised as being capable of prolonged motoring into a tide, or headwind, or chop, or all three.
> 
> It won't cut it, unless you have a very big battery bank indeed, and a lot of time to charge it.
> 
> For example, 25 hp (shaft power at the prop shaft) for 6 hours is about 112 kWh delivered, and probably about 1/4 more than that is needing storing to deliver on it. They will not try to deliver that at 12V, but, if they did I calculate the energy storage to be (corect me if I am wrong)...
> 
> 112 kWh * 1.25 = 140 kWh = 140,000 Wh = 140,000*3600 = 504 MJ
> 
> .... call it E.
> 
> If you are to find E from your battery bank, then...
> 
> E = current*voltage*time
> 
> E = I*V*t
> 
> Make the product of I*t the subject...
> 
> I*t = E/V
> 
> Say, for argument, your power is delivered at 12 volt...
> 
> I*t = 504,000,000/12 = 42,000,000 amp.second
> 
> = 11,666 Ah
> 
> My current house battery is 275 Ah.... that is about 1/42 of what would be needed for 6 hours motoring.
> 
> That was 6 hours motoring, and I'd need 11,666 Ah to do it, discharging the batteries to nil to do it.
> 
> My current tank capacity will keep the motor running for about 30 hour.
> 
> Pls correct me on this one there guys. Did I get it wrong?


The calculations are correct, however they are based on an incorrect first assumption. The SolidNav motor is not a 25HP DC electric motor: that would be tremendous in size and weight.

The literature states the SolidNav Explorer has a Maximum Current of 150 amps and a Continuous Current Maximum of 100 amps. Thus:

100 Amps x 6 hours = 600 Amp-hours _(not 11,666 Ah)_

Theoretically, on a 48v 275 Ah house battery you could run for about an hour at full speed, however most batteries are not rated for 100A continuous discharge.

275 Ah / 2 / 100 A = 1.375 hours

Remember that for a PMAC motor, current and torque, voltage and rpm are linearly related.

So a more practical and efficient configuration would be to gear-down to use lower shaft RPM and a higher thrust propeller that would run at 20-30 A and thus yield a 4-6 hour range.

275 Ah / 2 / 20 A = 6.875 hours, and 275 Ah / 2 / 30 A = 4.583 hours

As with an ICE, Speed and Distance would depend on LWL, displacement, hull shape and sea state.


----------



## tjaldur

For two years, 2007 and 2008 I used an electric motor on my dinghy to go ashore from my buoy. The dinghy was inflatable and did not weight much. The motor power was 30 pound thrust. In the dinghy I used an 80 amp battery, to comfortably lift in and out of the dinghy and aboard. With this combination I could go around 4 NM on each charge. The advantage as I see it, was that I did not need to store gasoline aboard. If I the battery was empty, it would still be fairly easy to row the dinghy as the motor does not weight much. It was considerate to the other boat neighbors to arrive silently to my ship if I returned late. The cost of charging was small as the whole electric system was charged by windmill and/or solar cells. Occasionally with the main engine or a diesel generator.


----------



## TSOJOURNER

*I second Wolfsong....*

I have a Cal 28 with a Yamaha 9.9 high thrust installed in the lazarete. I couldn't be happier with the outboard (installed inboard) but it leaves me with the inability to turn the outboard for steering. This means I have to keep at least 2.5 knots forward speed so I can turn with the rudder and make my 90 degree turn into my slip and then quickly put into reverse to keep from over running the dock. Needless to say........I have already over run the dock once when the motor stalled while switching gears. Having a strong removable trolling motor which I can steer in all directions mounted on the back of my boat WILL be my next major purchase. 
Keeping with the original spirit of the thread, I think if your day sailing or just need a boost for getting in and out of the marina then I can see a big benefit of having an electric drive. However I wouldn't rely on it alone unless I had a helluva generator to match. I do like the idea though.


----------



## TSOJOURNER

Diesel/Electric Locomotives have 8 sets of wheels with 8 traction motors (sometimes 6). The big advantage is the instant torque availble from an electric motor right from start at low rpms. Lots of startup grunt.

Now, how about a single diesel gen and 4 electric driven props on a boat.


----------



## TSOJOURNER

*Auxilary Sailboat vs. Motorsailor*

I stumbled onto this thread via google while researching the SolidNav unit.

Not sure if any of the participants are still reading, but felt compelled to respond.

First, I am a separate human being from the CEO of SolidNav and his various friends, split personalities, etc.. 

Second, I was pretty interested in the SolidNav unit, but that single post by their CEO really put me off -- I'll now be looking at Electric Yacht, Re-E-Power, etc.

Third, to Rockter and ChucklesR, I respectfully submit that whether or not an electric motor makes sense depends on whether one is a sailor, an auxiliary sailor, or a motorsailor.

My current boats (Ingrid 38 -- Rockter: sounds similar to your double-ender and Santana 22) are engineless. If the wind dies, we break out the oars (sweeps for the little boat, sculling oar for the big.) The standard question at this point is "Well, what if you have to row upwind in chop?" This is not the response of a sailor. If there is wind, sail. Period. Rowing is for absolute calms, when you need to get in or out of a tight spot. Sailing engineless (especially in a big boat) can be boring, nerve wracking, hard, but possible. Our sailing forefathers got all over the place without engines in boats that were much less handy in stays than most modern boats. Hardy folks like the Pardeys, the Hiscocks, Don Street, etc. etc. prove that it is still possible today. The key is that your boat must be set up to sail really well, especially upwind.

Which leads to the auxiliary sailboat philosophy. Frankly, rowing gets pretty old pretty quick! If we accept that a sailboat engine is there for convenience not safety (motorsailors will disagree -- see paragraph below), then there is a place for small auxiliary kickers to move sailboats in a dead calm. The old rule of thumb used to be 1 horsepower per ton. Again, for the auxiliary sailor there is no question of motoring at hullspeed for days. If you want to cross oceans, hoist your sails.

chucklesR: I sail a lot on a buddy's Gemini 105MC. Great boat -- being a monohull guy my only complaint is like most cats it lacks helm feel. One of the things I like about my friend's Gemini is it's light, fast, has easily driven hulls, and only draws 18" with daggerboards up. My buddy recently upgraded from a 1.5HP electric trolling motor to a 5HP electric outboard. Yeah, you read that right.  The motor is only for moving the boat at a slow walking speed while docking. The only reason he has an engine at all is that he has an upwind slip with a crazy, narrow, dog-leg final approach. He's a great sailor and he makes it work. I think for auxiliary sailors where you motor out of a tight spot for an hour, cross a bay (or an ocean) then motor into a tight spot, there just might be a place for an electric motor. (And again, I'm a neutral potential consumer here, not some wild eyed devotee or company shill.)

Finally, there is the motorsailor philosophy. Rockter, if you're talking about motoring for 8 hours at a stretch, this sounds like the camp you're in. No shame in that I guess, but let's be honest and say that on your boat, it sounds like it's the sail rig that is auxiliary... 

- Ari


----------



## COOL

This is an interesting thread,
Ari thank you for bringing it back to the light.
If you are rowing an engineless Ingrid 38, then
you are certainly pretty far from the mainstream,
but I identify with several points in your post.
Firstly I concur that many people these days use
their boats like powerboats with auxiliary sails.
This is in part because many modern production
boats really only sail well in ideal conditions, ie. reaching
in 15 knots TWS. They have poor sailing characteristics
in light air due to the excessive weight and wetted surface
of their voluminous hulls. Many do not sail to weather well.
Back on topic, I realise that electric propulsion is not the
right solution for everyone but it appears to be ideal for the
way I and many other people use their boats.
It is very common for people to only use the their engine
for a few minutes at low rpm to get out of or into the slip.
This is the worst possible application for a diesel engine, which
wants to be run under a load. The electric does not need to be
started or warmed up at idle, just put it in drive. This is a handy
feature you blow a tack and find yourself drifting into a jetty.
I can not wait to ditch my diesel and clean out the oily mess
beneath it and install a quiet and clean golf cart motor in its place.


----------



## TSOJOURNER

*Rowing*

Cool,

I try not row my sailboats at all. That's the point... 

- Ari


----------



## COOL

Aroostifer said:


> Cool,
> 
> I try not row my sailboats at all. That's the point...
> 
> - Ari


Understood. I am very patient, and 95% of the time 
I find that I can get where I am going under sail, eventually.
Light airs do not deter me, the only time propulsion is needed
is when the wind is up and blowing straight down the fairway
to my slip which is too narrow to short tack in.


----------



## MedSailor

Quite the thread we have here. Who would have thought that a topic could cause more angry than anchor choice. 

I've been interested in electric propultion for quite some time, but as Cam and others have pointed out several times in this thread it is not more efficient pound for pound, dollar for dollar, or by most other measures. I won't argue with the disadvantages, as they've been well explored on this thread and are quite valid. What I feel is lacking from the particular discussion is the other aspects that electric and electric/hybrid have over conventional diesel.

What attracts ME to electric/hybrid systems is similar to what has attracted me to hydraulic systems in the past. Here is what I like:

1: Silent motoring (or nearly with a very well insulated genset)
2: Easier to mount a dual prop setup (still only one diesel generator) for better maneuvering and redundancy.
3: Lots of options for motorsailing. 
4: Instant availability of power from the electrics in case of sail failure or diesel genset failure. 
5: The possibility of sitting at anchor and slowly augmenting your fuel supply by generating power. 
6: The possibility of creeping home (albet slowly) after diesel failure on a windless day.

Allow me to flesh out each of these advantages a little:

1: For starters I LOVE the idea of silent motoring. Yes I know sails are silent and that's why I use them when I can but the fact is that in the PNW with the type of cruising I do I motor about 50% of the time. I have seen many a small genset so well insulated that you can't even tell it's on dockside. Literally a whisper. I guess you "could" sound insulate your main motor this well, but I've never seen it done. It also appears that you can use a much smaller diesel for your genset (than you would for your main engine) and insulate it more easily with off the shelf technologies. If my motor were quiet I'd hate motoring less.

2: I'm getting better at docking, and less stressed as I practice, but I own a heavy full-keeled boat with a unidirectional wind powered bow thruster (large bowsprit). My maneuverability in harbor SUCKS. A dual prop setup of high torque electric motors would be a HUGE advantage in close quarters maneuvering. I would go out more often having confidence in a setup like this. I also recently had a large rug wrap itself around my prop on a windless day. If I had two props, it wouldn't have been an issue. Mounting one genset and two pods is possible, mounting two engines, transmissions, etc is just not possible for me.

3: The owner with the E-pod gemini (that Chuckles mentioned) talks at length about the options he has for motorsailing. I'm one of those sailors that doesn't mind using the nylon sails and drifting along all day. Problem is that drifting at 2 knots sometimes means having to use the engine at the end of the day to beat darkness or make a slack tide appointment. I would much prefer to SAIL all day with a couple amp hour push from the silent motors helping me along. Apparently they don't use much power in this role. I am much more likely to use this setup instead of fire up, warm up, and engage the rattlebanger. Once again, another advantage that would allow me to sail more.

4: Instant availability of power would help keep the stomach ulcers away. I try and maintain my diesel so that it won't suddenly die, but they all do sometimes. With my big heavy ketch I can't set my sails quick enough and short tack in a marina to keep off the breakwater. I keep my anchor at the ready, but an electric system that will continue to run if the diesel genset dies would eliminate this problem. Also if sailing and lines foul and suddenly I'm headed for a lee shore I have electric backup again in case the diesel doesn't want to start. It's a safety and stress-relieving feature. A safety feature I do without today, as when my motor dies I have exactly zero engine motoring time in reserve, but it would be "nice to have" even that 1 or 2 hours of motoring time in your batteries for after your diesel engine (genset in this case) fails.

5. Sitting at anchor topping up your tanks. This is more of a sate of mind really than a real savings. I compare it to the smirk of superiority that I see on trucks with biodiesel bumper stickers. It would take far too much to fill up an empty tank, even with a week at anchor in a windy sunny spot. But you could add some, especially with a nice windy night, and the though of it is nice.

6. We all know that mechanical things like diesel engines have two states of being: 1. Broken. 2. waiting to break. I've had my diesel die while out cruising and I've usually managed to creatively fix it at anchor. It would be nice though to have the option of crawling home at 2 or 3 knots using your battery bank if your diesel genset dies. Can the electric setup fail? Of course, but it's another tier of redundancy, much like an outboard to back up your main inboard. Recently when the rug wrapped itself around my prop and we had EXACTLY 0 wind I had to call buddies at my marina to come fetch us in outboard powered tenders. Had we even 1 knot of wind I could have sailed most of the way home. I still would have been screwed trying to dock with nylon sails in a close marina in 1 knot. With the electric setup I could have limped home at 2 knots using low amps from the remaining motor and even docked myself. I've also had the engine die in wind. We sailed into anchor but sailing into anchor would be easier with a little electric backup even if only for the final maneuvering in the (hopefully) wind-protected anchorage. I love redundancy and self sufficiency and this would add another step.

The technologies are not mature right now. I thought E-pods were a good bet until I saw the photos of the rusted out ones and the stories of poor service. Other companies have hot-headed CEOs.  So for now they're not good enough for me to fork over more than the cost of a regular repower but hopefully soon they'll get more reliable, cheaper and hopefully batteries will get better as well.

Here is a link to the gentleman with the dual E-pod gemini. He has some really good real world data (including real amperage usage vs speed graphs) on his setup as well as a good explanation of some of the advantages that aren't normally listed when people compare the technologies side by side.

Epods in Use
speed vs. amperage From the link to this page:"(update: the epods actually take half the power indicated on the chart to reach the speed),"

Regards,

Medsailor (not affiliated with anything electric or diesel)


----------



## mitiempo

Wow! I have just read this thread from beginning to here and when you take out the irrelevant comments about business practices and Giu's 4 strange posts you're left with this:
If you want more than an hour or so of electric power you have to have a generator or a hell of a lot of batteries. If you have to have a generator, why not just have an engine? Why buy an electric motor, controller, and lot of batteries and still have to have an engine? 
The E-Pod example I've seen on this site E-POD 3000+ - Petaris' Photos
ends up leaking and corroded in a short time. To me the only configuration that makes sense is to use the boat's original shaft and a suitable propeller - moving to a vulnerable saildrive type unit like the E-Pod is a step backward.
If you daysail and plug in at the dock, maybe it would work. But the references to moving through the doldrums and plugging in at dockside at your destination for a long term cruiser just don't make sense. Any cruiser I know that heads offshore seldom ties to a dock as there are very few in many places and where they exist doesn't want to tie to them anyway. Better peace and quiet and breezes at anchor. So that theory doesn't work either. 
In my local cruising area motoring is very common in the summer months. We have narrow channels, light winds or no wind and tidal currents of 7 to 10 knots in some passes (actually higher is a few places) and when slack water arrives you don't drift through at 1 knot with bare steerage way, you use the engine to get through quickly and efficiently - no matter how much of a purist you'd like to be. The engine has to be relied on and for more than 1 hour. When you get to your desired destination you don't plug in to charge as in the nicest places to cruise to (Desolation Sound being the best example) there's nowhere to plug in - just like the best foreign destinations you anchor because that's all there is. Maybe in Southern California you can go from dock to dock but we can't here (and don't want to anyway).
Battery charging as has been posted is best reserved for house batteries for the boat's systems (lights, refrigeration, etc) and unless you want to look like a floating solar panel store the power you generate has to go to this instead of the propulsion system.
No, until battery technology reaches the point when you can continually drain your batteries below 50% charge (way below) and recharge them quickly it's a no go in my opinion. At this stage electric propulsion for everyman is in the Model T era (if that advanced) and most of us are going to stick to our horses until it makes a leap or two in technology.

ps
Our friend SolidNav gave the link to his facts page in one of his first posts and everybody seems to have missed a fairly critical point about his numbers. His range figures are all hours to 80% depth of discharge for the batteries in his example. While it makes the numbers look better the batteries aren't long for this world with that kind of use. see below.


----------



## Mark F

Hi Mitiempo,

I'm not going to read through all the posts but I thought at some point I posted my real-life performance in this thread.

I have motored for seven hours at 4 knots and did not use half of my battery reserve, SolidNav Explorer with 200 amp hours in two banks.

It is a lot of batteries (8) but the boat (Ericson 27) doesn't seem to mind. 

If you moor your boat you would have to get creative with charging. Around here Monterey Bay/San Francisco Bay the vast majority of boats are in a slip with shore power.

It's a shame that people with no hands on experience with a new technology will dismiss it as inferior. My electric motor suits me fine and is superior in every way from previous motor.

It sounds like electric propulsion isn't for you but I'm guessing it is a viable (superior) option for 80% of the sailboat public.


----------



## mitiempo

Mark
I too tie to a dock with shorepower (the one in my avatar), but in B.C. the normal summer holiday for many is to cruise up the coast to Desolation Sound which is one of the largest pristine marine parks in the world - no docks, so no shorepower and many other B.C. cruising areas are also barren of ac power. Sometimes you might tie up to a log boom in a bay but mostly anchor for the night. This is what makes it a great cruising area and if you're more adventurous and have more than 2 weeks you can go farther north where there is even less civilization. While in a 2 week trip I guess you could tie to a dock every night if you planned it carefully most don't want to. When I think of the times I have tied to docks over the years it has often been rafted on the outside of a fishing boat with few amenities. So no. it wouldn't work for me or a lot of the people in this area. And we wouldn't want it any other way. At the risk of making it even more popular I'll post a couple of pics. 

I have a few questions for you though. How deep do you discharge your batteries? Do you have a battery monitor to see state of charge? What is your top speed? How large are the battery banks? What propeller are you using? What was the cost all in for the change to electric? What was the engine on your boat before the change?

ps Your profile shows you have a 1969 Ericson 23


----------



## tomwatt

I spent way too many hours last evening reading this thread, looking for information and to answer my questions concerning the prospects of electric for my boat, a Bristol Corsair. Outside of adulation for Giu's incredible boat, I came away with the distinct impression that the technology isn't quite 'there' yet for most applications. 
My boat uses an outboard configuration (in a well), and I did note that there was a report of success using a trolling motor in an application similar to mine. So I'm debating going down that road. There is a saltwater fishing boat application called a "trim and troll" that uses twin motors that seems like a good prospect. For my application, the saltwater electric trolling motors by Torquedo and Minnkota seem like a decent enough choice, and with only a few exceptional instances, I don't intend to 'need' to motor for any distance, and solar panels should recharge my bank until the next time out. I can scull pretty well, but I don't know about sculling my little tub effectively. It's certainly not set up for rowing.
And when it comes time to navigate the Cape Cod Canal or the ICW, then all bets are off.


----------



## tommays

The Pardeys have and 8hp and you can read about there ethanol fuel issue right on this page


----------



## tomwatt

Thanks Tom. Except, I hate to sound dense (I feel a little like the dog when someone is pointing to the stick - go get the stick - looking at the finger instead of the stick) but you mean someplace in this thread? If not then I don't see it... if so, I'll plow back through and find it, that part I can handle.


----------



## tommays

And its fairly sad that your better facts seem to be whose the real sailor rather than even post pictures of some of your working real world installs


----------



## smackdaddy

Just curious...

Do any of the current electric motor products use the prop to generate power? I remember seeing a wind generator (don't remember the brand) that you could replace the air rotor with a prop and lean the thing down into the water to generate power.

On the face of it, seems like it would be a good option to be recharging the bank while sailing using the prop itself. You could potentially get days of charging on a passage.

BTW - the build quality of that E-pod was truly embarrassing.


----------



## tommays

Hardy folk like the Pardeys, the Hiscocks, Don Street, etc. etc. prove that it is still possible today. The key is that your boat must be set up to sail really well, especially upwind.

When you use people like the Pardeys to make your case for motor less sailing you have to keep up to date as there always great to learn from BUT did buy and outboard as a necessary evil










I can say with proven facts you need 4HP at the prop to move an 8000# boat and the big thing working against electric is the PROP as any off the shelf sailboat prop is a massive energy waster as a comprise to the drag when sailing










Torqeedo Electric Outboard is the ONLY company that has done the engineering work necessary to provide and efficient prop fro electric drive

You guys should be able to provide some pictures of you working electric drives drives rather than deflect with whose the real sailor


----------



## smackdaddy

Tom - dude, you just leapfrogged me with the same post! Impressive. Somebody get JagsB over here. I smell a wormhole conspiracy.


----------



## tomwatt

Agreed the Torqeedo 4.0 seems about the right size for my application... to put in place of a 9.9 hp 4 stroke. But it ends up running about twice the cost of its gas equivalent, and still leaves me struggling to recharge on an extended trip.


----------



## Mark F

Hi Mitiempo,

That's a beautiful place you live!

I used to have an Ericson 23 (also electric) but now have an Ericson 27. 

I understand your concern about range with the summer trips you do , it's not a trivial issue. Also not insurmountable. 

My boat had an Atomic 4 then a 6hp outboard. 

I have a PakTrakr battery monitor. I find the SOC reading pretty useless as it is set for different max and empty states of charge than my batteries and the two banks are different from each-other. I watch the volts. After 7 hrs at a 20 amp draw I was just under 48 volts, maybe 47.9. I also had +/- 52 volts left in the second bank. I typically use very little current.

Top speed with a 12x10 fixed three (fat) blade prop is 5.8 knots (110 amps). You will eat up amps fast at that rate. 4 knots at 20 amps is what I use if I'm going to have to motor for a long time. I do take a hit on sailing speed with my current prop (1/2 knot?). I have a Campbell Sailor (skinny blades) that I want to try but it is right handed instead of left handed and I need the left handed prop walk to get out of my slip . To switch from right to left handed props I have a patch plug that switches the + and - on the low voltage forward/reverse switch (my transmission).

I've got about $6000 into my electric auxiliary.


----------



## Mark F

This is a link to SolidNav's you tube video of my boat;
YouTube - SolidNav - Electric Sailboat replacement for the Atomic-4, 2gm20 and other marine diesels

Mark


----------



## mitiempo

Mark
Just watched the video. It's impressive. $6000 is pretty affordable. If I were to do this I could see a few improvements though. One is combining all batteries in one bank as that gives you more usable amps especially with the large amp use of an electric drive. I'd put a real battery monitor on so I'd know the amps in and out accurately as voltage can't give accuracy until the bank is rested quite a while. The extra life of the batteries will easily more than pay for the monitor which would only cost about $250. 
Why do you need a left handed prop to get out of your slip? The Campbell Sailor backs better than most 3 blades and I doubt you'd have a problem - especially with all that torque. What I don't really buy is the power regenerated under sail. The numbers in the video are 200 watts at 6 knots - at what voltage? If it is 48 volts that's only 4 amps. There's just no way to regenerate enough as far as I can tell.


----------



## Mark F

My main reason for two separate banks is redundancy. I came to sailing through aviation (hang gliding) and have grown to respect redundancy. I also thought, to extend range it would be nice to be able to charge one bank with a portable generator while using the other bank for propulsion. In real life (so far) I've never had to do that. 

I understand the Peurket Effect dictates a bigger bank will provide more available amp hours but from what I have read at the rate of current draw that I use it's not that big of a factor. In the past I have had an issue with a battery that started to go bad in one bank and while I sorted that out I had a good bank to keep me sailing. 

The PakTrakr monitor does give me amp draw among other helpful information to keep my batteries healthy (that's how I found the weakening battery). You are right that knowing amp draw is absolutely necessary. The most I have seen as far as regeneration is concerned is 4 amps at 48 volts. 

I have a tight slip that gets some significant surge at times and having my boat walk to starboard is helpful. That said I will be installing the CS at some point.

Thanks for your interest, Mark


----------



## TSOJOURNER

*Pardey's vs. MacDonald's*



tommays said:


> The Pardeys have and 8hp and you can read about there ethanol fuel issue right on this page


Tom,

Are you talking about this thread?

http://www.sailnet.com/forums/gear-...tsu-8hp-4cycle-tech-questions.html#post544669

If so, those posts are by Larry and Susan MacDonald, not Lin and Larry Pardey.

Or were you talking about another post? If the Pardeys are using an outboard as an auxiliary these days, I'd be interested to read about it. (Sincerely not sarcastically.)

- Ari


----------



## tommays

Sorry about that my mistake as i had read about Larry and Susan MacDonald finally giving into a motor


----------



## mitiempo

It would be worldwide news if Lin and Larry put an engine on Taleisin!


----------



## TSOJOURNER

tommays said:


> And its fairly sad that your better facts seem to be whose the real sailor rather than even post pictures of some of your working real world installs


Hey Tom,

Not sure if you were talking to me. I'll try to upload some pics of my real world oar installs. Very, very non-electric. 

More pics of my boat at:

Macha, 6/1/08 - Lyons Imaging :: Our Galleries

To the other guy, those pics of Desolation Sound look beautiful. Again, I'll say that your boat philosophy depends on your priorities. If your deal is you want to cruise when there's no wind, then a motorsailor might be the best bet.

Why is it that we think "motorsailor" is an insult? It just is what it is, right? 

My boat's builder and previous owner sailed her down the coast from Bellingham to San Francisco, where I bought her. He had sailed engineless up around Puget Sound, Gulf Islands, etc.

Down here we're blessed with really good afternoon thermals in the summer -- 20 to 25 knots pretty much every afternoon, so that definitely makes it easier to get around without an engine. Even in flukey areas and flukey seasons, it's possible to make it work -- but it does take patience and hard work.

Cheers,

- Ari


----------



## Mark F

3 1/2 years into life with the SolidNav Explorer and all is well ;-)


----------



## 510datsun

I know this is an old thread, but was hoping some SolidNav owners might be still following the thread.

I have all but the motor and relay for a SolidNav 5KW motor. I upgraded my unit to a Electric Yacht controller and display set up.

So, if you know of anyone who has a bad controller, I have good one for a reasonable price.
You could also use this setup for a DIY electric motor set up, just need a motor and 48v relay.


I'm also selling my complete 5kw Electric Yacht motor set up. Comes with everything you need. I'm selling the unit because I bought the boat with the electric already installed and an outboard too. I don't need both, and I do long trips vs short day sailing that require many hours of motoring. I do sail when I can, have enjoyed the electric for maneuvering in the harbor or just out for a day sail.
The Electric Yacht complete unit with 4 (100amp)batteries and charger would be $6000, asking 1/2 price, $3000 OBO
I have complete description and pics here:
5.0 KW Inboard Electric Motor For Sailboat For Sale


----------

