Electric Main Drive(s)

[zardinuk]

I think 1850 pounds of lead acid batteries in a catamaran are pretty bad. I think what is really going to make all the difference in these regenerative power systems is new battery technology.

There is a new type of lithium battery being manufactured right now that is making its way into toyota prius "plug-in" conversions. They have much more recharge cycles than traditional lithium ion batteries, lower internal resistance (greater efficiency and faster recharge times), they are cheaper to produce, and most important they don't explode, which has been the main concern with large lithium battery banks. They will still be more expensive than the lead acid. I'd give it 5 years before you start seeing these popping up in everything, right now the only consumer product that uses them is the dewalt 36 volt lithium power tools, these use the A123 M1 cells (http://www.a123systems.com). You can buy these packs for $100 on ebay, they have 10 cells in them, so that price you see is not what you might expect for cutting edge technology. RC Helicopter enthusiasts have been re-assembling them to power their heli's, because they end up being much cheaper than lithium polymer packs because of the 5000+ recharge cycles, compared with the LiPo's ~100-200 recharge cycles, although they are slightly heavier than the LiPo. For comparison, lead acid batteries get maybe 600-1000 recharge cycles. Other companies making them are valence tech (Valence) and lithium technology corporation (http://www.lithiumtech.com).

These batteries are a great advance, they should really cut down the weight, and will end up saving money in the long run.

[SeaKing]

I have just started to study this technoligy, I would like to be "ready" to make the change to some type of electric drive on our cat when a major failure occurs in the current yanmar saildrive setup.

I just found this page with links to some articles on recent boats. thought I'd pass along the link

Electric Marine Propulsion - Articles

enjoy

[fastcat435]

African cats Builds the Fastcat 435 Green Motion with retractable electric motors/generators capable of generating 4 Kw each @ 10 knots of speed
http://www.africancats.com/resources...on_ENG1467.pdf

[fastcat435]

African Cats Offer both the FastCat 435 and the 525 in a retractable electric motor/generator version the aim is to go fossil free with both these designs
Presently the units are being tested for 3000 hours in a testing basin before they are mounted on the first FastCat435
The press release can be seen @ http://www.africancats.com/resources...on_ENG1467.pdf
and any other information can be obtained from us info@africancats.com
Gideon Goudsmit

[flapsone]

Check out www.firefly.com new battery tech. should keep cost, weight and space down.

[fastcat435]

I have contacted Firefly several times but no answer besides the answer that they will come back to us , they do not seem interested in the smaller marine market.
We use Lithium Ion Phosphate batteries in the FastCast 435/460 total weight 275 kilo,s for a total usable power of 16.6 KW or one hour running at full speed 9.5 knots or 4 hours at 6.5 knots this is not taking into account any energy coming from the 840 watt of solar panels and the masthead mounted wind generator.
We will commence 2 atlantic crossing beginning of june with the wish not to use any fossil fuels over a trip of 15000 NM

[cferger]

Originally Posted by flapsone

Check out www.firefly.com new battery tech. should keep cost, weight and space down.

That url did not load for me. could it be Home - fireflyenergy.com ?

[flapsone]

Originally Posted by cferger

That url did not load for me. could it be Home - fireflyenergy.com ?

Yes it should be Home - fireflyenergy.com

[fastcat435]

We have just comitted ourselves to Lithium Ion Phospahte batteries made by
LiFeBATT LifePO4 , we will install 16 Kw of these new batteries with a total weight of
250 kilo,s or 550 lbs and they will work for 2 hours at 45 % power or 7 knots before we will actually need the generator to start up and this is not taken into acount what the 840 watt of solar panels will bring us or what the masthead mounted wind generator will bring in
In may of this year the New Green Motion will be launched with the complete system in place . we will extensively test this system on 2 diffrent ocean crossings for a total distance of 15000 NM and I will do a write up on the advantages and disadvantages of the system since I have made this trip with the identical cat but driven by 2 x 30 hp saildrives. It is my intention not to use any diesel at all or any cooking gas because the cooking will also be electric.

[PattyPR]

Hi y'all! Just wanted to let you know that Glacier Bay is signing up qualified people for electric boat rides during the boat show">Miami Boat Show. If you are interested in experiencing diesel-electric propulsion first-hand, you should definitely check this out.

More details here:
<www.glacierbay.com/news/miami_tradeshow.html>

~Patricia Lambert
Public Relations
Glacier Bay, Inc.

[rory mcleod]

Greetings to all from Australia

I have been reading with interest the discussions re
electric drive propulsion systems

I have done considerable research on the net & have to this stage only found drive systems that use DC !!!

regardless of voltage it is still DC

I have an electrical back ground & am new to the boating industary

Often a sizable generator is needed for other power requirements on a boat EG air conditioning & dive compressor
Question
why is it that an AC gen set is not used to feed a variable frequency drive VFD ( some times refered to as variable speed drive VSD )
these units are available today providing full torque at low revs
three phase opperation for smooth power & are reversable in direction for use at sea
the same gen set could charge batteries for house use when at anchor & change the propellor to be a folding style as the drag caused when at sail barley compensates for the power generated while sailing as a regenerate system
the AC drive systems are cost effective & the motors are also freely available

am I over simplifying the needs or have I just missed the point completly

I understand DC power is needed for house needs & to feed inverters when at anchor

The new Generators available today are very fuel efficient as well

Rory
Also use a wind generator to charge batteries as well

[Bruce Nelson Glacier Bay]

[quote=rory mcleod;247202]Greetings to all from Australia


Question
why is it that an AC gen set is not used to feed a variable frequency drive VFD ( some times refered to as variable speed drive VSD )
these units are available today providing full torque at low revs
three phase opperation for smooth power & are reversable in direction for use at sea the same gen set could charge batteries for house use when at anchor & change the propellor to be a folding style as the drag caused when at sail barley compensates for the power generated while sailing as a regenerate system the AC drive systems are cost effective & the motors are also freely available

Rory,

Certainly AC gensets can be and are used with VFDs. A couple of the reasons that rare earth permanent magnet motors and generators may be chosen instead for a given design is that they tend to be more efficient and smaller for a given power output, and shock hazard on the power bus may be reduced.

Kind regards,

N. Bruce Nelson
Glacier Bay, Inc.

[S/V Mother Ocean]

This has been talked about a lot on other forums. I went to the maimi boat show this past winter just to talk about repowering my cat with electric propulsion. There are different ways to do it. Glacier Bay has a "diesel eletric" system that is like a train locomotive. It uses a small generator to power big electric motors. The down side of this is that you still have to run a diesel engine. But you save fuel because it uses less fuel to turn the motors than an equal diesel engine. At the boat show they had their catamaran giving demo rides. We went out on it and it was pretty cool. they had two (one in each motor well) gen sets turning motors in each hull it was quit and peacful. the only sound was the boat moving thru the water. They let us drive and I was impressed with the instant tourq. It was about $50,000 USD to install the system, ( 2 whole systems, 1 for each hull)

I like this company and would probbly go with it when the time comes to switch over. Except it uses 144V DC, and everything has to be switched for that.
E motion Hybrids This is the person that started Solomon teq. but sold out and started his own company because he didn't like the direction they were going. His idea is that you use 144 volt DC to run things. There are a lot of things good about this line of thinking in that it takes less to run things and you get more amp hours out of the same batt bank. Think that 24v Dc uses 1/2 the amps as the same appliance that is 12v DC. The down side is that you have to convert the whole system over and the reduce current down to 12v Dc to run things that are 12v DC, IE: VHF radio ect... They basicly blew off the concept of solar panels and wind gen unless you have 12 panels in order to produce 144v Dc power. Now on his web site you can watch videos linked to you tube that explains his theroy, and one of them going out with a reporter only useing solar power for the whole trip.

Now the down side is that it is expensive to switch every thing over. you need 12 group 27 batteries as a min (12v X 12v = 144v DC). and then a 144v Dc gen set, converters, engines and wireing, controls, ECT... cost was about $25,000 USD. The regeneration isnt that much and does not equal the amount used. The company said that if you had a 7 knt tide it might recharge it enough while on anchor.

Here is another system that uses 48 V DC. It also uses the control cables that are already on your boat. http://www.solidnav.com/explorer.htm

The basic concept is to trade a diesael engine that turns a small slightly pitched prop a lot of RPMs, for an electric motor that turns a large, deep pitched prop at slower RPMs,

To retro fit a boat not designed for those systems would be hard and not have it look like ****. Might be better to buy one set up for it.

There needs to be something in the middle. I was going to repower and put golf cart motors in and run them on 24v Dc, sun and wind recharge ( load up the hard top with as many panels and wind gens as possiable), and with a small DC gen set if needed. I havent crunched numbers so it's still in the pipe dream stage for me.

Here are links to this topic on other forums.
View topic - Electric propulsion : Cruisers Forum : Latitudes & Attitudes Magazine

Renegade Cruisers &bull; View topic - Electric Propulsion

I am not an expert on this subject, this is just what I found out in my quest.

Good luck
Dan

[rory mcleod]

[quote=Bruce Nelson Glacier Bay;248750]

Originally Posted by rory mcleod

Greetings to all from Australia


Question
why is it that an AC gen set is not used to feed a variable frequency drive VFD ( some times refered to as variable speed drive VSD )
these units are available today providing full torque at low revs
three phase opperation for smooth power & are reversable in direction for use at sea the same gen set could charge batteries for house use when at anchor & change the propellor to be a folding style as the drag caused when at sail barley compensates for the power generated while sailing as a regenerate system the AC drive systems are cost effective & the motors are also freely available


Bruce

Thanks for your comments

I agree the size can be an issue at times
also the style of motor is of a concern as it can be a special thing to obtain
re the power ( voltage ) I feel safer dealing with 240 & 415 volts when compared to 144 v DC that can be a real nasty as it does not cycle
If I was to go down a DC path I would limit the voltage to 48VDC as a max from the safety side

I also appreciate the stand point from a company point of view re the Dc system
I am constantly reminded of the Gov of USA & the search for a way to get men on the moon
they went to 4 consulting companies & for a way to do so & each came back with the only solution!!
all 4 were different!!!!!!!

so with this in mind I believe we need to look putside the square & consider the boat electricity needs a a complete item
not just a power system for the propellor but the total boat needs

below I have copied a quote provided for an AC motor & VFD for interest
11kW, 2 pole (2800 rpm), 3 phase 415V AC motor.
Model M3201103HGA. See attached PDF brochure.
$1,457 inc GST
To start this motor I would recommend a generator capable of producing at least 28kVA for starting motors.
A basic VFD to use with this will be approx. $2,810. Probably a couple of hundred extra for the keypad door kit (which allows you to mount the keypad away from the drive).
Model NXL00235C5H1
The problem is, when you slow down the motor the cooling fan becomes less effective. To slow it down to 50 rpm you will need some sort of external cooling device to stop the motor from overheating.

yes it also is not ideal & is but the first quote I have had for such equipment & I feel sure I will get more info in time
I suspect I would be able to use a smaller Gen as the VFD has a soft start facility
moor research

Again Thanks for the input

P.S.
interestingly where the boat is currently moored I experience a 8 to 9 kt tide flow

Rory,

Certainly AC gensets can be and are used with VFDs. A couple of the reasons that rare earth permanent magnet motors and generators may be chosen instead for a given design is that they tend to be more efficient and smaller for a given power output, and shock hazard on the power bus may be reduced.

Kind regards,

N. Bruce Nelson
Glacier Bay, Inc.

thank you

[rory mcleod]

Originally Posted by S/V Mother Ocean

This has been talked about a lot on other forums. I went to the maimi boat show this past winter just to talk about repowering my cat with electric propulsion. There are different ways to do it. Glacier Bay has a "diesel eletric" system that is like a train locomotive. It uses a small generator to power big electric motors. The down side of this is that you still have to run a diesel engine. But you save fuel because it uses less fuel to turn the motors than an equal diesel engine. At the boat show they had their catamaran giving demo rides. We went out on it and it was pretty cool. they had two (one in each motor well) gen sets turning motors in each hull it was quit and peacful. the only sound was the boat moving thru the water. They let us drive and I was impressed with the instant tourq. It was about $50,000 USD to install the system, ( 2 whole systems, 1 for each hull)

I like this company and would probbly go with it when the time comes to switch over. Except it uses 144V DC, and everything has to be switched for that.
E motion Hybrids This is the person that started Solomon teq. but sold out and started his own company because he didn't like the direction they were going. His idea is that you use 144 volt DC to run things. There are a lot of things good about this line of thinking in that it takes less to run things and you get more amp hours out of the same batt bank. Think that 24v Dc uses 1/2 the amps as the same appliance that is 12v DC. The down side is that you have to convert the whole system over and the reduce current down to 12v Dc to run things that are 12v DC, IE: VHF radio ect... They basicly blew off the concept of solar panels and wind gen unless you have 12 panels in order to produce 144v Dc power. Now on his web site you can watch videos linked to you tube that explains his theroy, and one of them going out with a reporter only useing solar power for the whole trip.

Now the down side is that it is expensive to switch every thing over. you need 12 group 27 batteries as a min (12v X 12v = 144v DC). and then a 144v Dc gen set, converters, engines and wireing, controls, ECT... cost was about $25,000 USD. The regeneration isnt that much and does not equal the amount used. The company said that if you had a 7 knt tide it might recharge it enough while on anchor.

Here is another system that uses 48 V DC. It also uses the control cables that are already on your boat. SolidNav :: The first alternative for everyone

The basic concept is to trade a diesael engine that turns a small slightly pitched prop a lot of RPMs, for an electric motor that turns a large, deep pitched prop at slower RPMs,

To retro fit a boat not designed for those systems would be hard and not have it look like ****. Might be better to buy one set up for it.

There needs to be something in the middle. I was going to repower and put golf cart motors in and run them on 24v Dc, sun and wind recharge ( load up the hard top with as many panels and wind gens as possiable), and with a small DC gen set if needed. I havent crunched numbers so it's still in the pipe dream stage for me.

Here are links to this topic on other forums.
View topic - Electric propulsion : Cruisers Forum : Latitudes & Attitudes Magazine

Renegade Cruisers &bull; View topic - Electric Propulsion

I am not an expert on this subject, this is just what I found out in my quest.

Good luck
Dan

Thanks for your input as well see previous response to bruse from glacia bay
I have been to the sites mentioned & I have a liking for the solid nav system as it could be used for other power to drive other systems ( air cond compressor )
I am still curious as the total concept needs to be considered

Regards

Rory