Solar powered trickle charger

I store my boat in a carport type structure with no electricity. Does anyone use a solar powered battery charger to keep the stereo batteries charged. If so, is the charger any good?

I was looking at something like this:
http://www.consumersmarine.com/modperl/product/details.cgi?r=view&i=73196&aID=41B&cID=FROOGLE_731 96

The icp Sunsei model you show is a super tough solar panel that will do a good job for you in many instances. I recently bought my 4th solar panel from Sunsei for a sailboat project, and would not hesitate recommending the brand.

The panel shown in your link will deliver roughly 500 milli-amps, or a half-amp of charging capacity in full sunlight. That is 25% of what you get out of the 2 amp setting on most battery chargers, so know that the output is rather low. That being said, you will not ever over-charge or cook your batteries with that solar panel.

I had an old Chris Craft plywood cruiser a few years back; a real leaky old boat. The 1500 solar panel I had on that boat, (3 times the size of the one you point out) was able to keep the batteries topped off, despite the bilge pump running literally every 15 minutes, day and night. I never had to plug the boat into shore power.

Any power you put back into the battery will be better than none, but you might make an attempt at calculating your battery depletion and try to put some math together based on how much of a charge you need while the boat is stored. This will tell you if the solar panel you show will do the job, if you need to go larger, or if you can get away with a smaller one. It is totally dependent on how much power you need or want to put back into the battery.

Here is an oversimplified very basic example of the charging capability of the solar panel:
Assuming 8 hours of good full sun a day, for 5 days between boat use, based on a half-amp of current output, the solar panel you show will provide about 20 amps of charging over that time. That sort of charging will provide enough juice to run a basic stereo with no amplifiers for about four hours, (assumes 5 amp continuous draw from the radio) before the battery is back to its pre-charged state.

That does not sound like much, I know. Do not expect a solar panel to replenish a battery that has been completely depleted unless you want to wait a long time....

I hope that helps!

Phil
Kicker

Should be good for keeping your batts topped off. I've seen them for about 1/2 the price, if that's any concern.

Phil - This is great information, I appreciate your response.

My pleasure!
So you know, the panel I just bought is the Sunsei 1500,(or was it last years 1200?). It will, (hopefully) be the only charging / battery maintenance device on my little 22-foot sailboat. The battery system will run the stereo, (no amp) the TV and the running/nav lights, as well as the interior lighting for those rare weekends overnight in the quiet cove.
I believe in the power of solar and encourage it.
Good luck and let us know what you decide!
Phil
Kicker

this is a good one also, charger plus...
http://www.ase-supply.com/product_p/pt-735x302.htm

phil- I was looking at the Sunsei 1200 also. I am assuming I would need to purchase the charge controller if I went with a 1200 or 1500?

They also had one on costco.com that seemed pretty similar to the Sunsei 1200 and it comes with the controller. Any feedback on this product?
http://www.costco.com/Browse/Product.aspx?Prodid=11248679&whse=BC&Ne=4000000&eC at=BC|114|3241|3404&N=4035126&Mo=6&No=2&Nr=P_CatalogNam e:BC&cat=3404&Ns=P_Price|1||P_SignDesc1&lang=en-US&Sp=C&hierPath=114*3241*3404*&topnav=#

The Coleman solar panel is made by Sunsei. Not sure the differences, but I believe they just use older technology; not bad, just slightly less efficient. Yes, you probably want the charge controller. It depends on the size of the battery. Some huge batteries do not need the controller according to manufacturer docs; I just usually use the controller.

Thanks again for your feedback Phil.