Solar Powered Battery Charger

[Papa Dawg]

I am ingnorant on this subject so I am asking questions. Anyone use a solar powered battery charger? Are they convenient? Can you use them during the day as you fish to keep the battery charged? Expensive?

Any feedback will be good. I have a friend who asked me these questions last friday as we were trolling and I thought some of you would have some input.

[CatFan]

To do any good, they'd have to be pretty good sized. At least 50W per battery, which will cost you somewhere between $300 and $800 per battery. And that will just be enough to slow the discharge on a bright, sunny day. They are big too.

[robbor]

They are really expensive to get a panel powerfull enough to charge a battery with any real amount of power. I was going to see about using a solar panel and battery to run a pump for the 2 55 gallon barrels i have with fish in them.
So a small panel from harbor freight say, 5 watt and 12v.
5 watt divided by 12v equals .416Amps or 400 milliamps at best.
A small bilge pump uses about 2 amps, so the panel has to produce power for 4 hours in order to power the pump for 1 hour. Hope this help give you an under standing. I want to say at about full draw a battery charger usually provides my battery with 4-5 amps normally when i am charging it, then it drops down pretty fast.

[willsjwills]

I use an 8 watt system that's hooked up to my two trolling motor batteries all week. I only use the boat on week-ends, but the little panel keeps the two batteries up for me. Occasionally I'll use the electric charger, only if I've done a lot of trolling and plan to go back the next day. The panel came off an electric fence system that I bought for my garden.