Electric repower
- Thread starter Marc Bergmueller
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I am with Bill & Ross. This is an expensive & untested technology that is going to cost much more than a diesel engine. You can get a 3 cyl Yanmar 30hp engine for about $7200.
These electric systems are typically 24V or 48V systems. If you are using 6 volt batteries you need 8 6v batteries (or 4 12v) as a minimum. Assuming you are using Trojan batteries (215 amp) you are looking at about $230 per battery for the 6V units and this is going to give you marginal running time. These batteries weigh about 72 lbs each (8 batteries @ 72# = 576lbs). You can start figuring out the multiplier if you want any reasonable range. You still need your house keeping bank.
Now you need to start considering the footprint of this. Don't forget that your 576 lbs of batteries is going to cost you about $1800 + frt. and how long are these batteries going to last?
These electric systems are typically 24V or 48V systems. If you are using 6 volt batteries you need 8 6v batteries (or 4 12v) as a minimum. Assuming you are using Trojan batteries (215 amp) you are looking at about $230 per battery for the 6V units and this is going to give you marginal running time. These batteries weigh about 72 lbs each (8 batteries @ 72# = 576lbs). You can start figuring out the multiplier if you want any reasonable range. You still need your house keeping bank.
Now you need to start considering the footprint of this. Don't forget that your 576 lbs of batteries is going to cost you about $1800 + frt. and how long are these batteries going to last?
experience vs theory
Well I have always said that a man with an experience is never at the mercy of one with a theory. If it works then it works. If COOL is happy with it then he is happy and I'm happy for him.
I would note that there are generations of sail boats that did not have a motor.
My issues are I'm not just going out over night and have some very bad habits like hot water, plumbed water, anchor and running lights, oh yea and refrigeration. I could probably make everything but the hot water and refrigeration work with some LED and foot pumps. Now if they had a CNG powered reefer I'd be all over that. I know they have propane but you can't install a reefer on the cockpit rail so you meet the safety requirements.
Well I have always said that a man with an experience is never at the mercy of one with a theory. If it works then it works. If COOL is happy with it then he is happy and I'm happy for him.
I would note that there are generations of sail boats that did not have a motor.
My issues are I'm not just going out over night and have some very bad habits like hot water, plumbed water, anchor and running lights, oh yea and refrigeration. I could probably make everything but the hot water and refrigeration work with some LED and foot pumps. Now if they had a CNG powered reefer I'd be all over that. I know they have propane but you can't install a reefer on the cockpit rail so you meet the safety requirements.
My computer is on its last legs,
and is not dealing with photos
very well, but here goes nothing.
and is not dealing with photos
very well, but here goes nothing.
Attachments
OK, that worked.
The photo shows my 4 Group 31 12V batteries in series for 48V.
The DC motor is rated for 15HP peak, and 8HP continuous.
The motor is coupled directly to the Saildrive through a rubber
spacer and carrier.
The 48V 15Amp charger in the center, will bring the bank up
to 54 Volts in a few hours. At that voltage I calculate close to 8HP at
110Amps. With a 105AH bank, I will not be running at that power
for very long. The brains of the system, just out of view on
the left, is a 500Amp programmable controller.
The entire system with batteries weighs a bit over 300lbs.
Just the Volvo MD11C it replaced weighed 500lb, without fuel.
The engine compartment is clean, with no oil or fuel smells.
The diesel was good for 7 knots at WOT, and the electric so
far has peaked at just over 5 knots. The e motor works
much better for maneuvering in and out of the slip with
instant thrust in either forward or reverse. Speed control
is far better, as the electric can run at any RPM.
It is quiet and smooth to operate.
Starting from zero prior knowledge of anything electrical,
I installed the entire system by myself using a golf cart
schematic. Surpisingly, everyinthing worked exactly as
expected the first time I powered up the system.
After battling an uncooropertive diesel for the past
few years, I am beyond pleased with this alternative.
The photo shows my 4 Group 31 12V batteries in series for 48V.
The DC motor is rated for 15HP peak, and 8HP continuous.
The motor is coupled directly to the Saildrive through a rubber
spacer and carrier.
The 48V 15Amp charger in the center, will bring the bank up
to 54 Volts in a few hours. At that voltage I calculate close to 8HP at
110Amps. With a 105AH bank, I will not be running at that power
for very long. The brains of the system, just out of view on
the left, is a 500Amp programmable controller.
The entire system with batteries weighs a bit over 300lbs.
Just the Volvo MD11C it replaced weighed 500lb, without fuel.
The engine compartment is clean, with no oil or fuel smells.
The diesel was good for 7 knots at WOT, and the electric so
far has peaked at just over 5 knots. The e motor works
much better for maneuvering in and out of the slip with
instant thrust in either forward or reverse. Speed control
is far better, as the electric can run at any RPM.
It is quiet and smooth to operate.
Starting from zero prior knowledge of anything electrical,
I installed the entire system by myself using a golf cart
schematic. Surpisingly, everyinthing worked exactly as
expected the first time I powered up the system.
After battling an uncooropertive diesel for the past
few years, I am beyond pleased with this alternative.
$7200 installed?? Not up here
Look -if the question is "Is there in existence a packaged electric or hybrid system that is as cost-effective and reliable as a proven marine diesel or gas powerplant solution?", then the answer is obviously no. But the components themselves and the concept are well-proven and in common use in other applications.
The main reason that a dependable marine hybrid propulsion system isn't yet available is because until recently no company had thought it commercially viable or marketable. It's been much easier and more profitable to sell the same simple engines they've been selling for the last few decades. But if you google "marine hybrid drive", you'll get alot of hits, showing how many companies are working hard to bring this to market. The demand for hybrid cars has accelerated development in this area as well, and that knowledge and technology will be trickling down.
Nice job, Cool. Please keep us posted on your experience with this system. I don't yet think the 100% electric propulsion system is cost-effective, bullet-proof or long-running enough for the average cruiser. But I remain convinced that even in a 28 or 30 ft boat, a properly designed hybrid system can be equal or more fuel-efficient than a comparably sized internal-combustion engine alone, and it would have more maneuverability and redundancy... and we're simply waiting for a company to put together the right combination of components at an acceptable price-point.
If I had a beater-boat and some free cash (or sponsorship) I'd build a proof of concept myself, tomorrow. I might even play over the winter with putting an electric motor into a used outboard leg just so I can generate some numbers for discussion.
COOL regeneration???
NICE! Impressive, most impressive
Now can it generate while you sail? I figure I can always sail around the bay till the batts are recharged enough to motor in.
NICE! Impressive, most impressive
Now can it generate while you sail? I figure I can always sail around the bay till the batts are recharged enough to motor in.
Range: electric vs petro
Derfus; I don't think he uses the boat like that. he said that he only uses it for docking and can sail at all other times. Probably has a nice set of sails to accommodate light winds.
My concern would be having enough battery power after anchoring out for several days and then needing the motor to get out of a tight anchorage with contrary winds and tide. Now if the prop can drive the motor as a genset to charge the bats while I sail......
This is clearly not a "for everybody" solution but it does show what one man and a dream can accomplish.
Derfus; I don't think he uses the boat like that. he said that he only uses it for docking and can sail at all other times. Probably has a nice set of sails to accommodate light winds.
My concern would be having enough battery power after anchoring out for several days and then needing the motor to get out of a tight anchorage with contrary winds and tide. Now if the prop can drive the motor as a genset to charge the bats while I sail......
This is clearly not a "for everybody" solution but it does show what one man and a dream can accomplish.
Bill's right. As with all electrical systems on boats: It's how you intend to use your boat that determines the electrical system design.
Putting aside the electrical re-power concept for a moment, for a "regular" electrical system, if you are a marina hopper you don't need a big house bank. If you intend to stay out at anchorages regularly, you need a bigger house bank to avoid having to run your engine every day.
It's just like that for electric power: you need an energy budget to figure out the correct balance of USE vs DRAW-DOWN to determine recharging needs and, therefore, usable range under power.
Putting aside the electrical re-power concept for a moment, for a "regular" electrical system, if you are a marina hopper you don't need a big house bank. If you intend to stay out at anchorages regularly, you need a bigger house bank to avoid having to run your engine every day.
It's just like that for electric power: you need an energy budget to figure out the correct balance of USE vs DRAW-DOWN to determine recharging needs and, therefore, usable range under power.
We do have an inventory of sails that easily covers a wind range
from 3 to 35 Knots. Light air is no problem, the boat is nimble
and quick for a 36'er.
Bashing into a big sea under power will not be very feasible though.
In theory this system is capable of re-generating from the prop
as the motor is a generator, but I have not tested this in practice
and I will not rely on that capability. At this point we are reliant on
shore power for charging, which is fine. For recharging on the
hook I will have to work out a solar panel array. Some people
have used a gas generator, which gives them the ability to
run continuously with the electric, but I rely on sailing the boat.
It is not a solution for everyone, but it will become increasingly
more common as the technology advances. Cruising engine less
is not for everyone either, but I admire people that do it and
I embrace that philosophy.
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I looked into going diesel electric on my Oday. Not depending on the batteries only. Then you have 110 power when you need it .
Bill R:
I personally do not think they will ever be able to replace an internal combustion engine to power a boat. The only really practical way to do this is with the type of systems that some of the "believers" have mentioned and then add something like an on-board generator to recharge the battery bank.
I think that this is the technology that the Chevy Volt is using.
Once you do this, you may as well just have that little diesel running the prop and not pollute the earth with those batteries that need to be shipped to Asia to be recycled because of the laws in the USA not allowing this type of pollution to happen on our shores.
Maybe Scotty & Spock can develop a starship system that we can use?
I agree that these electric systems like Hunter is selling are fine for lake sailing, but they will not work well for the areas that we traverse between the California Delta to the SF Bay. (50-60 miles against a flood tide & wind on the nose)
I personally do not think they will ever be able to replace an internal combustion engine to power a boat. The only really practical way to do this is with the type of systems that some of the "believers" have mentioned and then add something like an on-board generator to recharge the battery bank.
I think that this is the technology that the Chevy Volt is using.
Once you do this, you may as well just have that little diesel running the prop and not pollute the earth with those batteries that need to be shipped to Asia to be recycled because of the laws in the USA not allowing this type of pollution to happen on our shores.
Maybe Scotty & Spock can develop a starship system that we can use?
I agree that these electric systems like Hunter is selling are fine for lake sailing, but they will not work well for the areas that we traverse between the California Delta to the SF Bay. (50-60 miles against a flood tide & wind on the nose)
The appeal of the system is that it is quiet and should be pretty darn troublefree if designed correctly. The downside is of course is limited range. If the batteries are sufficient you get several hundred cycles so that is a lot of day sails.
Nice for a day sailer who can more or less pick his conditions less good for a cruiser.
Nice for a day sailer who can more or less pick his conditions less good for a cruiser.
The dream
Hey Steve D
I would think that with a "properly set up boat" that does not need to by motored much, goes to windward well etc you would not be needing the motor that much and if you can supplement with solar, wind, hydro (using the prop!!!) to keep the electrical devices going this would be a workable setup.
The only thing I have not figured out is how to do refrigeration over long periods of time. hydro is the only thing that I've found that can supply sufficient current over time while sailing but I can't figure out how to stay at anchor for 30 days and still have cold beer.
Hey Steve D
I would think that with a "properly set up boat" that does not need to by motored much, goes to windward well etc you would not be needing the motor that much and if you can supplement with solar, wind, hydro (using the prop!!!) to keep the electrical devices going this would be a workable setup.
The only thing I have not figured out is how to do refrigeration over long periods of time. hydro is the only thing that I've found that can supply sufficient current over time while sailing but I can't figure out how to stay at anchor for 30 days and still have cold beer.
Low speed performance
Hey COOL, what kind of amperage do you think you are drawing when only going 1 knot? More specifically at 1 knot boat speed what do the fully charged batteries read on a volt meter?
Hey COOL, what kind of amperage do you think you are drawing when only going 1 knot? More specifically at 1 knot boat speed what do the fully charged batteries read on a volt meter?
buy a good anchor and pick you anchorage, Princess Louisa inlet gets what 10 knots twice a day. That should keep things charged. But 1 knot of current/tide is not too hard to find
I still have a bit more testing to do in this regard, and there is no
dedicated volt or amp meter in the system now. I do have a little
'toy' wattmeter that will give me all the data I need,
(volts,watts, amps, AmpHrs used etc..) but it can only
handle 130 Amps ,so of course I smoked the first one
when I got too excited with the throttle.
I think 10-15Amps will get me 1 knot, 30-40 Amps 3 knots ,
40-50 Amps 4 knots, and full throttle it pullls maybe 120 -130 Amps
which got us a bit over 5 knots with a slightly dirty bottom.
I plan to chart boat speed/ amp draw at various low speeds
when I get an opportunity.
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