Electrical supply and recharge for barebones boat.

[zz4gta]

I'm trying to decide on what battery and charging system I'm going to use for my boat. I don't want it to look like a kitchen inside. No interior lighting, no microwave, fridge, radio, etc. I like portable battery operated stuff. No wires to run, don't have to leave it on the boat, etc. However, I do want to obviously run nav lights and a depth/speed indicator. But other than that, I don't need anything else.

My questions are what size and type of battery do you all suggest, and what would be the best way to recharge it? I would like to do some over night trips and even some 3 day weekend type stuff. I saw the old "solar panel" post w/ 109 pages and just about fell out of my chair. After reading about a dozen pages I came to the conclusion that most of the specifics discused were refering to larger boats w/ lots of 'extras' on board. I just don't want to buy a lot more than what I need. Thanks.

[sailingdog]

A couple of questions:

First, do you leave the boat in the water or use a trailer?

Second, if you leave the boat in the water, do you have a shorepower post at the dock or is it on a mooring or dock with no power?

An AGM Group 24 battery with a small charger should do the trick... given your very limited needs. The reason I said an AGM battery, is that they don't self-discharge as quickly... and they're easier to transport, since they don't have a liquid electrolyte to spill.

If you trailer the boat or have it on a dock with no power or a mooring, I would recommend you get a small AC 10 amp smart charger and use that at home to charge the battery. Just carry the battery back and forth and connect it when you need it. This should suit your barebones style...

However, if you want to make things more convenient, and the boat is at a dock with a shorepower setup... install a proper ground power inlet plug, 120 AC panel, and one GFCI outlet, and then use a small waterproof AC charger to charge the battery. You should also install a DC breaker panel and wiring with a battery switch. The advantage of this, even though it is more work, is when you want to do work on the boat, you have easy access to 110VAC via the on GFCI outlet.

[SantaSailor]

On my 25 foot all I had was a single deep cycle. I used a single solar panel trickle charger that I left tied to the cabin top when I wasn't at the boat. It kept the battery charged during the week so I was ready to go on the weekends. The only thing I used it for was the nav lights, anchor light and a single cigarette lighter socket that powered my 1 million candle power spot light when needed. The solar panel plugged into the cigarette lighter socket to do the charging. It was nice, clean and simple.

[zz4gta]

Right now its trailered, but it will eventually be in a slip (I hope).
The dock that I'm looking at has power, but I like the idea of taking the battery home to charge. If I were to take it home to charge I would assume that it wouldn't last me 3 days of limited use correct? Would a small solar panel be the answer? Similar to what santasailor recommended?

[CharlieCobra]

My little boat has a maintenance free auto battery that runs Nav lights and one interior dome light for four nights without recharging. With the sailing instruments and portable radio or GPS plugged into it, it might only last three days.

[BarryL]

Hello,

When I had a Catalina 22 I used a single group 24 marine battery and a small solar panel. I never went on a 3 day trip, but the battery was fine for a few hours of evening sailing and a cabin light or two. During the day the panel provided enough power to keep the battery charged.

I used this panel from Harbor Freight:

http://www.harborfreight.com/cpi/cta...emnumber=41144

It's on my O'day 35 now, keeping the batteries charged over the winter.

Good luck,
Barry

[SantaSailor]

That looks like the same/similar one that I had on the 25 but it had a cigarette lighter plug on the end instead of the aligator clips. I had a cigarette lighter socked mounted just inside the main hatch that I used for the spot light, charging the cell phone and also plugging in the solar panel to recharge the battery. It made it easy.

[hellosailor]

"3 days of limited use "
You need to do an energy budget. Figure out the wattage drwan by your lights and instruments, multiply that by 60 hours (or whatever) and then you'll know how many watt-hours and amp-hours you need in the battery.

Without even looking...at a minimum you've got a masthead tri with a 20-watt bulb in it, used for 12 hours times two nights, twentyfour hours at 20 watts, 480 watt hours right there, assuming you are sailing at night. If you don't sail much at night...a very different story.

Take your total watt hours, divide by a nominal 12.6 volts, that's HALF of how many amp-hours you need in the battery. Half, because batteries die very quickly if you cycle them more than 50%.

You may find that investing in LED nav lights--which are expensive--makes your solution much cheaper in the long run, because they draw so much less power. But first, you need to run the numbers, for the type of sailing you do. For a 3-day race running everything, even two Group 31's might not be enough.

[soulesailor]

How about goin' old-school? Get some oil lanterns for your nav. and anchor lights. You can get your speed off your hand-held GPS, that leaves only the depth sounder, which you could either use a lead-line for or go without. Many people will agree that depth sounders are finnickey, anyway. Primitive, I know, but a lot of sailors managed their way around the world with no electricity. It may be worth considering, depending on how you want to use your boat and how you want to modify it.

[Freesail99]

Since we just took a side step into LED navagation lights, anyone ever use these?

http://www.ledshoponline.com/marine_led.htm#masthead