Solar Power

[hcrisp]

Their is a 10 watt solar panel onboard which I didn't use when I launched last year. Now I want to put it in service. I can't remember the brand and I am away from the boat. I do know the following: manu rating - VOC: 23.8V, ISC: 0.78A. It tests at VOC: 23.2, ISC: 0.73 A. It definitely charges the battery. My question is will it over charge?
Is a controller needed on a panel of this size? I was told it was too small to over charge.

[The Garbone]

On our last boat we had a 15watt panel with a 7 amp (max)controller. Worked like a champ and never overcharged the banks. You do get some loss with a controller and 10watt is pretty small. I would use a controller but you may get away without one as it is more of a maintenance charger and less for recharging.

We run a 50watt panel and 10amp controller now, love never having to connect to shore power.

[smosher]

I have a 20 watt panel and its the best add on I did.

get a cheap solar controller from ebay, less than $ 10

Steve

[sail_flathead_lake]

Morningstar makes a little charge controller called a SunGuard. I had one on my last boat and it was cheap, easy to install, and worked great. I plan on installing one on my current boat when I get a chance.

[lat 64]

Morningstar makes a little charge controller called a SunGuard. I had one on my last boat and it was cheap, easy to install, and worked great. I plan on installing one on my current boat when I get a chance.

+1 on the SunGuard.
About $35 in Alaska.
Buy good electrics—it's a boat for cryin' out loud!

I wish I had bought one that has an LED light for charging. Oh well.

Oh, and never, that is never, ever, ever get the polarity reversed. Pop goes the controller!.

[hcrisp]

Charge controller

I like this company. This controller new is cheaper than Amazon and the people are intelligent and helpful.

https://www.emarineinc.com/Used-SunGuard-SG4-5-4-5A-12V-Charge-Controller

[sastanley]

hcrisp, The ones you linked to look fine.

I have two of these Sunforce controllers on my boat. One for each bank...The panels are 5w and 3.2w. Even a small panel, any unregulated solar panel is generally bad news..the only respite for the battery is night time.

http://amzn.com/B0006JO0XI

[GregH]

Definitely get yourself a small PWM charge controller for a system of this size. You don't need anything fancier like a MPPT controller. Not only will having a charge controller help to maximize your charging, but stop when the battery doesn't need it and also prevent any current traveling back up the system from your batteries.

[Mo]

Hi Howard, as you know I'm no electrical wizard. Costco, here in Canada sells a 70 watt solar charger kit, Coleman, with regulators etc all in one package. $179 I was tempted to buy one and install it but can't justify it for how I use the boat. The thing is about 18 inches by 18 inches big and would need mounting...however, it is the Blue type stuff that is supposed to work well in variable cloud conditions etc.

Here's what my boat does and has...so
- I live 3.5 miles from the boat...so I'm there almost daily...it's a strange thing if I'm not down to the boat.
- Boat has 100 amp alternator.
- We use the boat on weekends during the summer, no electric water pumps so just use lights.
> all lights are LED. Some of the interior lights are the normal Perko with LED bulbs replacing the incandescent bulbs...works fine.
> my son has autism and we leave a light on for him all night in the V berth.
> anchor light, led as well, on all night.
> kids play with computers, DS's etc...
> VHF radio...on during the day under way
> Satellite radio...on sometimes but we don't worry about power with it.
> Chargers for cell phones
> Chartplotter on while underway..always
> Autopilot on while underway...almost always.

Batteries are Two AC Delco 27's They are new this year at a cost of about $260 Cdn....18 month replacement warranty. So, my batteries are up all the time and only get partially run down on an overnighter on the weekend. Allot depends on how much you use the boat. I know I can expect 3 good years out of these with the conditions I run them through. I can also spend a chunk of change installing and maintaining a solar panel and still have to replace batteries in 3-5 years as well. If living on the boat or away from the boat solar chargers are the answer...but I don't think they are necessary for us guys coming and going daily. If my batteries are not up something else is wrong.

[hcrisp]

How we use our boat

Mo, you said the magic words "can't justify it for how I use my boat". My boat has very modest electrical needs. So modest that I don't even need a "house" battery. The A4 takes care of everything. But, the siren call of solar power is strong and tempting...

The decision whether to get solar power or FWC turned out to be a no brainer.
At this point solar would just be a toy, but a very attractive one.
I'm not talking about the little 10 watt that came with the boat. That I'm keeping and have ordered Shawn's controller to keep things safe.
Howard