Thread: Solar Charging

Most of those chargers would be doing good to keep a fully charged battery from losing charge in storage. You are talking $500-$800 for something that can recharge a battery that isn't fully charged.

Originally Posted by CatFan

Most of those chargers would be doing good to keep a fully charged battery from losing charge in storage. You are talking $500-$800 for something that can recharge a battery that isn't fully charged.

?? Can you restate this so that it makes sense to a simple fella like me?Do you mean a $500-$800 for a solar charger that still won't do what is expected of it?

I have two different solar chargers one big one small, the small is the one off the electric fence box. it will keep the battery charged just fine. started with good battery and it keeps it up with no problem, I also have a large one that is about 4 ft. long and 2ft high, and it will charge a low battery in 8hours. I use it when I am camping, and it's ok. but two hooked together would be better.I have charged a battery, to dead to start the truck. and in four hours it started. but it was still weak. hope this little diddy helped.

Originally Posted by Crappie Reaper

?? Can you restate this so that it makes sense to a simple fella like me?Do you mean a $500-$800 for a solar charger that still won't do what is expected of it?

To recharge a battery like a TM battery after it's been used, you need at least 3-5 amps to overcome the battery's internal resistance.

At 14.5V, which is the charging voltage for a battery, 3-5 amps is 43.5 to 72.5W. You could probably deal with 50W, but your battery will suffer in terms of longevity because of the low recharge rate, which means the battery stays in a discharged state for a long time.

50W panels run around $300 for cheap ones, to well over $500 for good ones. These things run at around 23V naturally, so you need to use some type of charge controller. That's another $50-$100 minimum.

After you have the money tied up, you end up with a very delicate 2ft by 3ft piece of expensive glass that only works on sunny days, and never works as well as a much cheaper electric charger. I can't even keep from breaking my sunglasses in the boat :o

A small generator with an onboard charger will recharge the batteries much faster, in any kind of weather, day or night (a big deal if you want to fish two days in a row), and the cost is in about the same range.

The panels are better than nothing, but almost every option, including hauling the batteries home to charge, is cheaper and better for the batteries.

The little fence charger panels are usually worse than nothing at all. They can bleed charge out of the battery, and even in full sunlight they only put out 600 to 800 milliamps, which means even ignoring battery self discharge, they would take around 200 hours of direct sunlight to recharge a battery. They can't even keep a fence charger battery charged, and they are about a tenth the size of a boat battery.

Here's my alternative to a solar charger for my boat batteries. It's called a stayncharge, charging system. It charges my batteries by using the left over power from my car altenator, while the motor is running. It charges my batteries on the way to and from my fishing destinations. I've been using this system for over 5 years, with a couple plug updates, and i'm very satisfied with it's results. I'm using the basic model and it's charging 2 batteries for me. I found it to be a good alternative to my solar charger that i attempted to use.