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Catalina/Capri 25/250 Sailor's Forums

Catalina 25 Specific Forum

Alternator vs. Solar

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Jared
1st Mate

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USA
70 Posts

Initially Posted - 01/27/2004 : 17:15:26

Well, the time has come to buy a new motor... I have been shopping around and have found a few options. I am looking at a 8hp Mercury (or Johnson) 2-stroke ($1300) and a 9.9hp Yamaha 4-stroke ($2100). It sounds like to me the 8hp will be fine power-wise and I don't mind the 2-stroke, the only difference in these two from my standpoint is that the Yamaha has an alternator/electric start.

Most of my boat time is going to be daysailing once a week or so. There will be a couple overnighters a even less 2-nighters, but not much beyond that in all likelyhood. The only charge I would need to maintain would be a couple days of interior lights and anchor lights and VHF and depthfinder - I don't have a CD player or anything like that.

Am I better off with an alternator, or go no alternator with a solar panel and regulator (much less than the $800 difference)? If I go solar, the thing will sit and the dock and recharge itself all week without having to leave it plugged in. The solar makes so much more sense to me - or am I seeing this all wrong. I would appreciate anyone's experiences and/or opinions.

Thanks.

Jared Jamison
86 C25 #5354 FK/TR "Saba Rocks" Richmond, VA

Edited by - on

Raskal
Navigator

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USA
162 Posts

Response Posted - 01/27/2004 : 17:49:25

I don't have experience with solar panels but in principle one wants some redundancy in the system--having an alternator gives you a permanent recharging source whatever may happen with the solar gear. Redundancy can be a key to safety if you need battery power for the VHF at dusk or during a storm and the batteries are low!

It's worth considering also that when you go to sell your boat the potential buyer might not like messing around with the solar apparatus and not having a recharger on the motor might hurt resale value.

Rich Kokoska

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Leon Sisson
Master Marine Consultant

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USA
1893 Posts

Response Posted - 01/27/2004 : 17:58:48

Jared,

I have a 9.9hp Yamaha 4-stroke with alternator/electric start, two 11w Unisolar panels, three batteries (two group-27 house bank and a group-24 cranking), and two battery combiners. I typically don't run my engine much. The solar panels seem to keep up with my once a week or so daysailing power needs. Each battery combiner includes a little green LED that comes on when at least one of the batteries it's combining is about fully charged. A few days after a daysail, the green LEDs are both on, indicating that the solar panels have about paid back the power drained while the boat was in use.

On longer trips, I need to suppliment those charge sources about once or twice a week with a shore power charger.

I suggest you calulate a power budget for your worst case needs (a long weekend aboard for instance), and then figure out how large a house bank it would take to have double that capacity. Then figure out how long it would take either your choice of solar panels (at a realistic output rate for your lattitude, dock location, boat orientation, etc.) or the engine alternator (at a realistic engine RPM) to replace that power.

My guess is that 100AH to 200AH bank and one or two small solar panels will cover your modest power needs. If you have a bit more charging capacity than needed for one daysail per week, then it's OK if it takes the system a little more than a week to catch up from a long weekend of hedonistic power consumption. Just try not to discharge your batteries more than 50%, and keep in mind that a battery that's not fully charged, or on its way there, is a battery that's quietly sulfating to death. And since all lead acid cells have a significant rate of self discharge, that last point favors the permanent use of at least one solar panel or some other automatic charging source.

-- Leon Sisson

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ClamBeach
Master Marine Consultant

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3072 Posts

Response Posted - 01/27/2004 : 20:59:29

For the very modest power needs you describe, I think a decent deep-cycle marine battery coupled with a small solar panel will do the job... supplemented by occasional sessions with a shore-powered battery charger before/after overnight trips.

If you intend to do extended cruising, the equation changes.

Another solution is to take the difference in motor costs and buy a Honda EU1000 generator. 18"x9"x15" Very quiet (53 dB). 29 lbs. Gives you AC cabin power and recharges your batteries anytime you want. Double duty as an emergency/utility generator.

http://www.hondapowerequipment.com/eu1000.htm

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ClamBeach
Master Marine Consultant

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3072 Posts

Response Posted - 01/27/2004 : 21:02:55

Edited by - on

Dave Bristle
Master Marine Consultant

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Djibouti
10005 Posts

Response Posted - 01/27/2004 : 21:17:22

You're double-clicking again, Clam...

What about gel vs. wet cells? I've heard that a gel battery can be discharged further without damage, self-discharges less, and is somewhat safer (even upside-down). I've thought about buying one when my ordinary battery dies, but it refuses to even show any weakness, charged only by the outboard. I guess that suggests I don't need to spend the premium for a gel cell.

Edited by - on

ClamBeach
Master Marine Consultant

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3072 Posts

Response Posted - 01/27/2004 : 22:48:50

Funny, I don't remember double clicking on that one... but the web site failed to refresh fully after I clicked submit reply... so I clicked refresh again. Must have double-posted then.

Only downside I've heard on a gelcell were some reports out of Baja cruisers that they tend to die in very high temperatures... Like a Baja summer. No danger of those temps in SW CT right now I reckon.

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JimB517
Past Commodore

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USA
3285 Posts

Response Posted - 01/28/2004 : 20:25:00

I have a 6 amp alternator on my Honda and I don't even bother hooking it up UNLESS I am going on a week or longer cruise.

A single 11 watt flexible solar panel on your boat during the week will keep your battery full charged when daysailing. Only the interior and nav lights use any serious amount of power. When cruising, double them up and use 2 or 3 panels. You don't need the alternator unless it's cloudy.

That's assuming you have a manual start option.

Edited by - on

oldsalt
Admiral

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USA
578 Posts

Response Posted - 01/29/2004 : 21:38:33

I believe that gel cell batteries require different charging voltages and rates than wet batteries and I'm not sure that they will provide adequate service life when charged with the unregulated output of an outboard's alternator.

Automatic chargers that are designed for both wet and gell type batteries have settings for each.

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sailgal
Captain

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USA
400 Posts

Response Posted - 02/03/2004 : 11:51:10

I'm thinking of adding a 11 watt flex solar panel. I have two NC-24 Nautilus deep cell batteries attached to a perko 1-2- all switch which are charged by my yamaha 9.9 alt. Question is in connecting the solar panel. Is that done by running right to the perko switch, (which at dock is turned off) or split direct to the two batteries? I've read in the past that an 11 watt panel won't cook the batteries, is that true or would you also suggest a regulator? thanks.

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JimB517
Past Commodore

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USA
3285 Posts

Response Posted - 02/03/2004 : 12:09:28

I run mine to a regulator, then to the battery switch. An 11 watt panel will not damage a 75 amp hour battery (or two). The regulator is not needed. Since I have 2 panels for cruising, I have one.

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JimB517
Past Commodore

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USA
3285 Posts

Response Posted - 02/03/2004 : 12:10:16

by the way, they come with cigarette lighter plugs, if you have a 12 vdc plug on board, you can just plug the panel in.

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Jared
1st Mate

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USA
70 Posts

Response Posted - 02/03/2004 : 13:02:50

So, if you just plug into the cigarette lighter with the battery switch turned to 1 and 2, then it will charge both batteries? If so, that is just too easy. Can you run something off the lighter too - say with a splitter, use the panel and a GPS at the same time and not fry the GPS?

Sailgal - which 11 watt panel are you thinking about. I am going to get one about that strong too. If you look at my other post about Solar Suggestions - someone suggested a source to get a 10W flexible panel that is a cosmetic second. Or, are you getting one at West Marine?

Edited by - on

MikeM
1st Mate

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72 Posts

Response Posted - 02/03/2004 : 13:43:08

I would go with a redundant system with using the alternator and a solar panel. I have the same set up, and found myself sailing right from the mooring and never using the engine (I would rather sail than motor around.The solar panel was a big help there as the lack of engine use would have drained the battery. However, if the battery did die you could always start the engine to get instant power with the redundant system.

Go for both solutions. I recommend a Uni-Solar Flexible Panel that you can wrap around the boom (at least 11W) and make sure you include a controller to avoid battery over-charge.

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sailgal
Captain

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USA
400 Posts

Response Posted - 02/03/2004 : 22:13:22

Hey Jared I saw your post and peaked at the link but didn't see any info on the seconds. I figure you have to call them direct to inquire. Actually the panel I was looking at was the Uni-Solar FLexible [imghttp://www.cetsolar.com/images/flexiblemulticolor.jpg][/img]
at Boaters World. (The one Mike mentions)Their price is $149. ((also shopping around) I figured I'd try to gain more info before I buy. Still a bit confusing with regards to connecting to two batteries and the fear of cooking them (I get a lot of sun in Fl. and no shade in my slip) Wonder if the "seconds" is the same specs as the Uni-Solar. I'm going to research further.

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Ed Montague
Captain

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USA
499 Posts

Response Posted - 02/06/2004 : 14:13:58

Jared, My Magellan GPS is designed to run on 3 volts DC, two 1 1/2 AA batteries. The GPS external power cable from a 12V outlet has a built in regulator the takes the 12V down to 3V. The flexable solar panel I have puts out 22VDC at max. I don't think I would risk that much voltage directly to the GPS set up. It makes more sense to run the solar panel charge thru the batteries and let them regulate the power levels to other instruments.

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Captain B
1st Mate

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USA
88 Posts

Response Posted - 02/08/2004 : 17:30:41

Seems like you'de have to run an egine quite a bit to charge the batteries with a 4-6 amp altinator.

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77Gypsy
Captain

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USA
356 Posts

Response Posted - 02/13/2004 : 18:40:43

i would go with a motor with an electric start, sure an alternator is great but how much motor running time are you getting, probably not enought tocharge your batteries. A solar panal will give you a gradual charge throuout the week so when you go out on weekends you should always be topped off.

Edited by - on

seastream
Navigator

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USA
242 Posts

Response Posted - 02/13/2004 : 21:34:14

Gel cells are indeed 'neater' than wet cells but it's also true that they ARE more finicky in their charging requirements. I was going to get a pair of gels but went with wet cells since they're cheaper and better at handling the output of most OB motor charging systems...which are often unregulated. If you boil a bit of electrolyte off through excessive charging, it's easily replaced...just add distilled water. If you dry out a gel through excessive charging, it's dead, finished and needs replacement. Additionally, unless you sail virtually upside down often, there's no worry of spillage from wet cells. I'd say anyone that buys gels should also buy a dedicated regulating system with them.

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Jared
1st Mate

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USA
70 Posts

Response Posted - 02/23/2004 : 17:16:24

Well, I ended up with the best of both worlds. I found an outboard that is probably more reliable than either the Mercury or Johnson because it has a Japanese name on it. I got the 2-stroke, 8hp, Tohatsu LS (Nissan with another sticker), with electric start and an alternator for not much more than the 2-strokes with no alternator. I got it from onlineoutboards.com and went with the Tohatsu because they were out of the Nissan and Nissan no longer makes 2-strokes and are running out of the Tohatsu's as well. I will get the solar panel a little later in the spring when I buy new batteries. I should have the motor in about a week and then hopefully be back out on the water within the month. Spring is near...

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oldsalt
Admiral

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USA
578 Posts

Response Posted - 02/23/2004 : 19:48:44

Regarding the reliablity of the Johnson; them's fighting words.

As for the Tohatsu, I believe that they make them for Nissan who merely places the Nissan brand on them. Good iron.

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dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/24/2004 : 00:07:42

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Jared
 ...I found an outboard that is probably more reliable than either the Mercury or Johnson because it has a Japanese name on it...<hr height="1" noshade id="quote"></blockquote id="quote">

I hope your new outboard lasts as long as my former 22 year old Johnson 9.9 that started on the first pull and lived the first 16 years with the original spark plugs.

Or as long as my Dad's 25 year old Merc which, unbeknownst to my father, spent some time at a depth of 12 feet, courtesy of my little brother

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oldsalt
Admiral

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USA
578 Posts

Response Posted - 02/24/2004 : 19:49:15

I as well, wish that your new Japanese iron lasts as long as the 2 cycle 9.9 hp Evinrude Yachtwin that I bought in 1983 along with my boat. I replaced it with a new Johnson 9.9 Sailmaster because it looked kind of worn, and although it never gave me the slightest problem, I wanted to get my hands on another 2 cycle outboard while they were still available.

And I thought the white color would look cool on my boat.

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