Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 06-04-2006, 23:59   #16
Senior Cruiser
 
delmarrey's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Now in Blaine, WA
Boat: Modified Choate 40
Posts: 10,702
Images: 122
The nice thing is the motors will recharge the batteries while sailing. although it will cause a little drag. But on a Cat, that's not much............._-/)
__________________

__________________
delmarrey is offline   Reply With Quote
Old 07-04-2006, 05:12   #17
Registered User
 
RandyAbernethy's Avatar

Join Date: Aug 2005
Location: Carib
Boat: Saint Francis 50 - Swingin' on a Star
Posts: 170
Lagoon 420

The current Lagoon spec includes 2 x 10KW motors and a 13.5KVA genset. You may not move out too quick under power but you'll have plenty o' juice to run your AirCon, dive compressor, green underwater lights and basement disco.
__________________

__________________
Randy

Human history becomes more and more a race between education and catastrophe. -- HG Wells
RandyAbernethy is offline   Reply With Quote
Old 07-04-2006, 05:21   #18
Senior Cruiser
 
Talbot's Avatar

Cruisers Forum Supporter

Join Date: Jun 2004
Location: Brighton, UK
Boat: Privilege 37
Posts: 3,579
Images: 32
I am not a great fan of the concept of trailing the prop to generate power. I would rather add a few more solar panels!
__________________
"Be wary of strong drink. It can make you shoot at tax collectors - and miss."
Robert A Heinlein
Talbot is offline   Reply With Quote
Old 07-04-2006, 07:33   #19
Registered User
 
henryv's Avatar

Join Date: May 2004
Location: Ontario
Boat: PDQ32 & FP Helia 44 on order
Posts: 242
electric motor power

As a designer I have always found that when selecting electric motor they are invariably much smaller in terms of horsepower ratings than one would need for a gas or diesel engine. The electric motor develops full torque at start up and can be run constantly at it's full horsepower rating while an internal combustion engine has little torque at low rpm and is generally not expected to run continuously at it's full power ( full throttle ) level. The electric motor also does not require extra power to run it's own generator and water pump cooling.

There is some good power / efficiency info at www.feys.org - their systems are too big for most sailboats but most of the info is still applicable.
__________________
henryv
henryv is offline   Reply With Quote
Old 07-04-2006, 08:04   #20
Registered User

Join Date: Oct 2005
Posts: 341
Send a message via Skype™ to gosstyla
I agree with Gord that the genset is probably a little light. I use 2 x 28kw gensets but of course my motors are 2 x 35hp.

At first using the props to charge seems like a good idea but I don't believe anyone has worked out the details. I know the Solomon system does not (did not) regulate the power from the prop to charge the batteries nor did they have a good way to disengage the charging.
__________________
gosstyla is offline   Reply With Quote
Old 19-04-2006, 18:21   #21
Registered User
 
RandyAbernethy's Avatar

Join Date: Aug 2005
Location: Carib
Boat: Saint Francis 50 - Swingin' on a Star
Posts: 170
Gosstyla: So your boat is diesel/electric? If so how do you like it?

Henryv has a great point when it comes to parasitic power consumption. A starter alternator and an additional high output house alternator (injector pump, water pump">raw water pump, etc.) add up to a lot more complexity and lower usable power at the prop. The Lagoon folks indicate that the electric 420 will have much more apparent power than the 410 did. It will be interesting to see if this and the prop charging kinks mentioned are worked out.
__________________
Randy

Human history becomes more and more a race between education and catastrophe. -- HG Wells
RandyAbernethy is offline   Reply With Quote
Old 19-04-2006, 21:12   #22
Registered User

Join Date: Nov 2005
Location: Full Time Cruising
Boat: 1990 Morgan 41 Classic
Posts: 54
OK, I think it might be time to have a more detailed discussion of the electric power plant on the Lagoon 420. My local Lagoon dealer was nice enough to provide me with a document that takes all the Lagoon marketing info, presentations etc and clearly answers most of the questions one might have about this technology. Lagoon publicly claims that they have taken orders for about 75 420's already and even today, there are still some questions outstanding about regeneration boat speed and gel vs acid batteries. There is a lot of excitement about the 420 but I am in a wait and see mode. If I were to buy a 420 for local sailing I think the electrics are an interesting option. For cruising or circumnavigation, I just dont get it. Here are some of the things I am concerned about. I am very anxious to understand this power plant better so any debate, new information or pointing out of inaccuracies would be helpful: (pm me if you would like a copy of the document)

1. Motor battery charging, Motor Operating, house battery charging and all AC power is provided by the 1 generator. If this dies, you have lost all ability to motor or have any form of electricity on your boat, even to operate instruments. Yes you can regenerate or perhaps use solar panels but I am not sure how well all of that works. With 2 diesels, you have a full backup to charging of your batteries, powering the boat and providing AC power through an inverter. I would hate to be in the middle of nowhere with a storm coming and not be able to motor out of the way because my generator was not working.

2. The electric motors run off the batteries until they reach 80%. At 80% the generator automatically comes on and powers the boat with the batteries either in charge mode or offline. The time to get the batteries from 100% to 80% is anywhere from 1 - 2.5 hours depending on how fast you are going. The 2.5 hours is at 5 kts and 1 hour at 6.5 kts. They say "The best way to keep the batteries in excellent condition is to not sail using exclusively the batteries for more than 12.5 miles". The bottom line is that you may be running the diesel generator more often than not which defeats the purpose.

3. If the generator is being used so often I looked at fuel consumption. There are a few data points given that are based on load. Load varies depending on whether you are charging the batteries or not, whether you are charging the house batteries, or operating AC appliances. In these modes you use anywhere from .9 to 1.9 gal per hour. I read an article on the first Solomon powered 410 and they said the generator burned 1.5 gallons per hour while motoring. How much do diesel powered Cats burn per hour and do you use both engines? It looks like you could be using almost as much fuel in the electric configuration as with two diesels. What do you Cat owners find your fuel consumption is?

4. It was already mentioned that there is no redundancy when it comes to the generator and what happens if it dies. The electric power plant has some very complex electronics associated with it for power management, load protection and charging. Is there a concern about what happens to these circuit boards when there are lightening strikes in the area?

5. Battery cycle count is another item of interest to me. I have not seen any information on how many charge/discharge cycles the batteries can withstand which gives you a good idea of their lifetime. They say that you should not let them go below 80% to assure longer life, but how many times can you do this? Each time a battery goes through a discharge cycle it loses some of its depth of cycle. I am wondering how often these batteries have to be replaced and how much this costs.

6. One of the selling points is that the batteries can be regenerated by the props. Regeneration only takes place when the boat is moving faster than 4.5 kts and its estimated that 8.5 kts is when you have maximum regeneration. Considering that the props reduce your speed by about 1 kt, it seems you have to be moving at 5.5 kts or more to use the wind to regenerate. At the miami show I spoke to the engineer who designed the system and he claimed that his personal system takes about a day to charge back up to 100% with his solar panels assuming a very clear day. I have not seen any documents that show a way to hook solar panels up into the 420's main battery banks. Lagoon has no plans to offer solar or wind options at this time.

There are a lot of positives about having electric motors, but this system seems to still be very dependent on having a large diesel generator which still needs to be maintained like your existing diesel engines. You seem to lose quite a bit of safety associated with redundancy when you go to this electric drive system with not much saving in fuel. Incidently, I asked and there is not an option to add a backup generator. Its probably too big and heavy anyway.

So do I have it all wrong? Comments or clarifications are welcome.
__________________
laser is offline   Reply With Quote
Old 19-04-2006, 21:46   #23
Senior Cruiser
 
delmarrey's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Now in Blaine, WA
Boat: Modified Choate 40
Posts: 10,702
Images: 122
First off monohulls only have one system. So what do they do if they lose a motor?

You guessed it, other alterative! The same alterative can be used on a Cats, solar panels, wind gen's, water gen's or even a bicycle set up (regeneration).

Look at the new electric cars that are running around town now. They have the same basic set up as the Lagoons. A small gen set that runs the electric's when needed and going down hill & braking they recharge the batt's. They get 50 mpg+, and that's a gas motor, Make it a diesel and the savings is even better.

The City gov. here has basically given up on the CNG cars and gone to the new Prius/Toyota's.

Besides, that's what sailing is all about, going without motors. Unless you get stuck in the doldrums, but modern man should know where those are now………………_/)
__________________
delmarrey is offline   Reply With Quote
Old 19-04-2006, 22:00   #24
Registered User

Join Date: Nov 2005
Location: Full Time Cruising
Boat: 1990 Morgan 41 Classic
Posts: 54
delmarrey:

As and "aministrator" I would have hoped that your reply would have been a little more appropriate. I must have not been clear enough but I though my discussion was about the current diesel options on today's cats vs. the newly introduced electric power plant on the Lagoon 420.

It was not about mono vs. multi or a comparison to the Toyota, which is not a similar arrangement at all since you can run the car off either the gas or electric but the 420 can only be run off the electric with the genset providing the juice. If you took the time to read the post you would have read that Lagoon does not offer a solar or wind generation option as part of this system.

I am not sure what you were trying to contribute to the exchange but whatever it was, I missed the point. I hope some of the others are interested in talking about the specifics of this new system.

If you think my post was not approriate please let me know and I will take my discussions to another board. I felt your post was sarchastic at best and contributed nothing to a positive exchange of information. I guess this attitude comes with administrative privledges.
__________________
laser is offline   Reply With Quote
Old 19-04-2006, 23:25   #25
Registered User
 
coot's Avatar

Join Date: Feb 2006
Posts: 367
Images: 2
I think the point is that an electric catamaran with a single diesel generator is no more at risk than any diesel powered single screw boat. If the generator goes down in your Lagoon 420, you are in the same spot as I am if the engine goes down in my Beneteau. We would both be without an engine (though you would have some engine time before your batteries ran down), and we could both sail if there is any wind.

Of course, it is fairly simple to install a second generator if you require that redundancy. It doesn't matter that the boat manufacturer does not offer one. Beneteau didn't offer a generator in my boat, but I have one.

Lagoon may not offer solar/wind but you could design and install it yourself. It will not be a substitute for the diesel generator. Think about it: If a 4 foot by 2 foot solar panel is about 100 watts, how many do you need to match the 13,500 watts of the generator? 135 panels, totalling over 1000 square feet, costing US$80,000 and weighing over 3000 pounds. (For example, see SE-6000 panel on page 524 of the West Marine catalog; all numbers are approximations, but good enough for this discussion.) Obviously, solar is not going to replace the generator.

Solar will help you if you just want to top up the batteries. For example, if all your motoring is just to get in/out of the slip so you can sail the rest of the time, a few solar panels can be useful. This is probably what the guy is talking about when he says he recharges in "about a day" -- he didn't drain much energy out of his batteries. The benefit here is to not have to run the generator to top up the batteries when they are almost at full charge.

The control electronics are a critical component. If they go down, you are out of luck. (I understand the same may be true of some recent computer controlled diesel engines.)
__________________
Mark S.
coot is offline   Reply With Quote
Old 20-04-2006, 05:29   #26
Registered User

Join Date: Feb 2006
Posts: 192
"complex electronics" + salt water + high currents (+ lightning?) = bad thing.

sounds like one slip and you have expensive problems

I'll wait for Version 2.0 (or 4.0 more like)
__________________
Moby Dick is offline   Reply With Quote
Old 20-04-2006, 10:16   #27
Registered User
 
RandyAbernethy's Avatar

Join Date: Aug 2005
Location: Carib
Boat: Saint Francis 50 - Swingin' on a Star
Posts: 170
I think what Delmarrey is saying has merit; many folks have happily traveled the world with zero or one diesel aboard. You can fix a diesel when it breaks of course, at least if youíre carrying the appropriate spares. You loose the redundancy inherent in some cats but not all cats have two diesels. This is really a personal risk tolerance issue, the overall sailing world is far from standardizing on redundant diesels.

I do however see Laserís point regarding the loss of redundancy, and if youíre on a schedule (heaven forbid) or sailing in particularly nasty places, a backup could be fairly important. You can put in a second backup genset and it doesn't have to be a big monster if it's for emergency use. A 3KW Mastervolt genset weighs in at under 250 pounds and is pretty small. If the 420 system is reliable (big caveat), and you have the means to repair the genset along with some alternative sources of power (maybe solar and the props dragging) I think I could get over this issue (being a trade winds only type). This boat also appeals to the Birkenstocks/granola side of many of us, some luxuries can be traded for a feeling of good global citizenship.

Solar, wind and dragging the props are all noted above and are all solid, widely used means of generating power. Toward the 1,000 sqft of panels calculation, you would need this to generate the same current power provided by the genset in strong sunlight (as an odd aside the beam x LOA on the 420 is about 1,000 square feet, so if you were the nutty typeÖ). That said, it is pretty easy to get 1,000 watts out of 6 panels these days and while the sunís up theyíre on, you donít usually run the genset non stop for house operations (not if youíre careful anyway). Thus 13.5 hours of peak sun (two or three days of real sun) equals one hour of genset, or somewhere around 100 amp hours. You should be able to run basic instruments and house stuff on 40 amp hours (the daily dose from a strong set of panels). In regards to Lagoon not offering solar panels, I think that this is true of many manufacturers. Many solar panel installs are aftermarket, I wouldnít be scared off by this.

A good wind generator can produce 33 amp hours (per hour) in 25 knots of wind. Itís also pretty easy to get a Lagoon 380 up to 7 knots with both props dragging in around 15 knots of wind. I suspect the 420 will do better. I donít think youíll have a problem regenerating the batteries during a good portion of any sail. Not sure what the props do dragging at 7 knots but I understand it is even more substantial than a wind generator. The house bank on the 420 is separate as I recall and the motors should not be taxing the house batteries. Lots of folks make well planned passages using all of the power they need without turning on the diesel. If you avoid the horse lats and the doldrums you should have plenty to work with even without the genset.

As pointed out, running the genset when the screws are driving the boat defeats some of the purpose of the system, particularly if you use more fuel. In my limited experience, cats of this size burn 0.5 to 1 gallon an hour per diesel. While that is right in the quoted Solomon range I know that one of the goals of the 420 system is to do a better job there (will it? no telling). I have also found that gensets with their nifty housings tend to be quieter than your run of the mill drive diesel. If not then certainly one diesel is quieter than two.

The lightning issue is a serious concern. I am also curious as to whether they will use tinned wiring given the increased reliance on things electrical. House batteries cycle much the same way as I would imagine the drive batteries cycling. Good AGM batteries last several years in house banks.

All in all I love the concept and expect it to dominate sailboatings auxiliary power market in the years to come. I twill be interesting to see if Lagoon can pull off the necessary reliability to avoid a v1.0 stumble.
__________________
Randy

Human history becomes more and more a race between education and catastrophe. -- HG Wells
RandyAbernethy is offline   Reply With Quote
Old 20-04-2006, 10:55   #28
Registered User

Join Date: Nov 2005
Location: Full Time Cruising
Boat: 1990 Morgan 41 Classic
Posts: 54
Randy:

You have brought up some very good points. My intention was not to debate the overall concept of single vs dual etc. It is only to get other folks perspectives on whether the Lagoon 420 design is ready for prime time. I have no argument with mono's having a single engine and the fact that the reason I have a sailboat is to sail. I am happy to say that I will have the sails up as much as possible. I am buying a Cat for many reason's and one of them is the redundancy of the systems especially when a well planned passage turns out to not as well planned as one would have hoped.

I did ask about a spare genset and was told there were no plans to have it as an option and no planned space but I am sure you could probably find a place to mount it.

With your comments about wind and solar in mind I took another read through the information and the diagram of the system you posted earlier. The 420 main drive batteries are 72 volts. The genset puts out either 110V or 220V to the charger inverter that then puts out 72 volts 120A to charge the batteries. With this in mind, wouldn't you need a 72 volt solar panel system or wind generator. Is there such a thing or are they all 12V with the option to hook them up in parallel to generate more amps? The house batteries are 12V so you could charge them with solar/wind. Maybe the 72V issue is why Lagoon has not considered solar or wind options.
__________________
laser is offline   Reply With Quote
Old 20-04-2006, 11:04   #29
Registered User

Join Date: Oct 2005
Posts: 341
Send a message via Skype™ to gosstyla
Randy
How do I like Asanagi?
Don't know - it was suppose to launch last September, now June - maybe.

Both
http://www.ossapowerlite.com
http://www.alwoplast.cl
have some photos and info about Asanagi if you are interested. The info is not absolutely correct, but close enough.

Also, the ossa powerlite has several technical articles that discuss many of the questions being asked in this tread.

Re: electronics and lightning - I have spares for all the critical items.
__________________
gosstyla is offline   Reply With Quote
Old 20-04-2006, 11:33   #30
Registered User
 
RandyAbernethy's Avatar

Join Date: Aug 2005
Location: Carib
Boat: Saint Francis 50 - Swingin' on a Star
Posts: 170
gosstyla:

By all means post the photos! Oh the gallery is down, right (just a little rub Andy...).

Seriously though, I'd love to see some photos. Which boat is Alwoplast building you? Which Ossa system do you have installed? The Ossa system seems pretty interesting.

I have heard that Lagoon has an exclusive contract with the firm making their system (forget the name). Ossa and Soloman are left to partner with other firms.

Laser:

With the drive banks set up for 72 volts you would have to run separate 12 volt and 72 volt chargers just as the main genset does. Youíd have a starter and house bank at 12 volts (lets not run the house at 24 volts, huh?) and drive banks at 72 volts. This gets me thinking about the 72 volt bank. Those 6 batteries (12volts each I assume) are in series. If you begin to lose capacity on one or two you wont be putting out 72 volts. Iím sure that thereís some buffer provided for this but Iíd be interested to see how the system handles excess current and manages voltage issues.
__________________

__________________
Randy

Human history becomes more and more a race between education and catastrophe. -- HG Wells
RandyAbernethy is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
furling main sail mast into normal main usage? andreavanduyn General Sailing Forum 9 20-02-2009 09:52
furling main sail mast into normal main usage? andreavanduyn General Sailing Forum 1 10-02-2009 09:06
do I need a ring main? fjweaver Electrical: Batteries, Generators & Solar 0 02-07-2008 05:24
Outremer electric drive comparison test henryv Multihull Sailboats 1 13-07-2007 11:55



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 08:46.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.