charging batteries while motor is running?

[Sunking]

2panels of 100w cover an area about 4ft x 3ft..?

No John a single 100 watt 36 cell panel is 49" x 27" or just call it 4' x 2', so two of them minimum is either 8' x 2' or 4' x 4'. Either way it is 16ft2. Now where the heck are you going to sit? Jon Boats have 2 or 3 bench seats. Rear 1/3 of the boat and one bench seat is for operator, engine/motor, battery and transom.

The other thing that strikes me is I assume the boat is used for fishing. I do a little fishing and have a 2-man Bass Buster basically a plastic bathtub with a 10 hp gas engine on the rear transom, and a 50-pound Trolling motor on the front transom. But here is what I know about fishing: You get out on the water at dawn. shut down mid morning because the fish quit biting, and go back out a few hours before the sunsets when the fish start biting again. So if that is the pattern the boat is being used for, leave the panels on the dock and let the batteries recharge during mid day sun while you have lunch and afternoon siesta.

[Sunny Solar]

2 panels 4ft x 2ft 6in could easily be mounted on post at front of boat ,that way they take up no room in the boat.and make a nice flat sunshade. wind is not going to be much of a problem.And as for making the boat top heavy thats rediculous. as they weigh less than 2o lb each.
I already said that when fishing or smoking the batteries will be recharging.

Your wild statements that the panels will need to be as big as a house to recharge them in a day ..and will sink the boat is crazy..and contradicted in a later post by you.. 12 volt Marine batteries run 60 AH on the low end up to 200 AH on the high end
Using your figure of 5a from a 100w panel and using 2 panels and a discharge of 50% a 60ah battery will only need to be charged by the panels for 3 hrs that is very easily done in one day. (mabe difficult in the middlle of winter in the middle of Alaska,excepted)If we take the 200 ah battery and discharge it 50% then that can be replaced by 30ah on the day of use and the other 70ah then next 3 days of non use.

Your post about 1hp to 3hp motors and drawing up to 200 a is a far cry from your post that now agrees that batteries are from 60ah to 200 ah and no one using such a small boat would be using such high power from a 12 v 1000 ah battery . Remember the person said he had a 12v motor.,and simply wanted to know if solar panels would be of benefit . and to that question its definately a YES . And they dont have to be house size and they wont turn his boat into a submarine and he wont have to sell his children to slave traders.

[Sunny Solar]

I have a simple question…… I have a jon boat that runs on 12 volt power. I want to hook up a solar panel or panels to charge the two batteries. My question is while on the water do I need to detach the panels while I’m running the motors. I would like to keep the panel/s attached so as soon as I was stop….no longer running the motor…. the panels would instantly start charging and I wouldn’t have to worry about hooking up and unhooking the panels. So is it safe to hook the panels up and just leave them attached?

Shawn its perfectly safe to leave the panels connected to the batteries while using the motor. But you will need a charge controller. The size of the panels is up to you but obviously the bigger you can use the less the batteries will get discharged and the quicker the batteries will be recharged. You didnt give the boats length but my guestimate would be about 12 ft and for that size 2x 100 w panels would be perfect if the total battery AH is below 200.

post mounted about 4ft? facing straight up and at the front of the boat would be my suggestion. but you may find it better at the rear of the boat, As I dont know how the layout is its hard to say which is best place.. you have to decide that.

[Sunking]

Your post about 1hp to 3hp motors and drawing up to 200 a is a far cry from your post that now agrees that batteries are from 60ah to 200 ah and no one using such a small boat would be using such high power from a 12 v 1000 ah battery .

John you need to quit drinking and making things up. I never said you need a 1000 AH battery, you made it up. Fact is 12 volt trolling motors range from 30 pounds of thrust to 200 pounds of thrust, and it takes 1 amp/1 pound of thrust. A 200 AH Marine grade AGM can easily supply 200 amps. So quit making things up and go back to Wind and Sun Forum.

[shawn walker]

hmmm

I’m a little confused now… anyone have any recommendations on a panel 2x4 wouldn’t be to large.

[Sunking]

I’m a little confused now… anyone have any recommendations on a panel 2x4 wouldn’t be to large.

Do a search for " 100 watt 12 volt solar panels". They are a niche product and pricey. Expect to pay $250 to $400 per panel.

[Sunny Solar]

Sunking yes you didnt say 1000ah battery But as you keep saying it could draw 200a A200 ah battery aint gunna last long.

Shawn if you think the 100w panels are a bit large for your boat pick something that will fit your needs.. As I said You didnt give the length of the boat so its hard to know exactly what size you want to use and how and where you want to mount them.. Its just that smaller panels become more expensive per watt than larger more popular panels..

I think you now have enough information to make a decision as to what you want to do, You now know that whatever size you use you are ok to have them connected to the battery and motor making no difference except to available power to the motor. More panel output is always going to be better if you have the money and space on the boat..

Happy fishing

[Kebast]

Look here

I’m a little confused now… anyone have any recommendations on a panel 2x4 wouldn’t be to large.

If you're set on doing this, look to spend around $600+. You'll need two small panels, or one larger panel. I'm not sure I've seen it stated, but are you running on a 12 volt system? Either way, you'll have to opt on a cheap charge controller and more panels, or a ~$250 controller and maybe one less panel.
My family had a 17 foot Jon boat when I was younger, it could give up 4x4 and still fit 3 people comfortably. Still not sure fitting it with solar is really worth the effort.
Search Home Depot for Grape Solar, though Russ mentioned these were China made products.

[russ]

Some assembly in Oregon to allow a USA built claim of some type with all components from China -