charging batteries while motor is running?

[shawn walker]

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?

[inetdog]

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?

Leave the panels connected. Even if they are not charging the battery, they are supplying current to the load which would otherwise have to be taken from the battery. Net result is still good.

Imagine that the panels could supply *almost* enough power to run the motor. After 1 hour running with panels connected, battery will be close to where it started, even though it has never actually seen any net charge. Without the panels, the battery would have been running the motor on its own for one hour and be significantly discharged.

[Sunking]

Well here is a good question that begs an answer. There is no amount of panels you can put on a Jon boat to do any meaningful work while afloat to charge your Marine Trolling motor battery. It would be silly to try and not to mention great possibility to sink your boat. Glup, Glup! It will take a panel the size of a house to recharge your battery in a single day. Do you think a little 2X4 panel will do anything other than recharge a Cell Phone battery in a day? I would love to see you try it so i can film it and post on Red Tube.

[Sunny Solar]

What is the current draw of the motor? If its less than 20a then 2x 100w panels would supply most of the power it consumes between about 10am and 2pm, but would drop off a lot outside those hours.

[Sunking]

What is the current draw of the motor? If its less than 20a then 2x 100w panels would supply most of the power it consumes between about 10am and 2pm, but would drop off a lot outside those hours.

JohnP good try, but you are still smoking Ganja and day dreaming in the Philippines and Australia. Yes John I know who you are and can track you.

2 x 100 watt panels are larger than a Jon boat and if standard 12 volt battery panels are used will deliver 10 amps or 120 to 150 watts to a 12 volt electric motor. Electric trolling motors are 1 to 3 Hp which require up to 200 amps. Nice try, but you do not fool me.

[Kebast]

50 amps

If it is a normal size trolling motor, most likely it is something like 50 amps max draw. 1 amp per rated pound thrust is a good estimate. Still, yeah would be using up a lot of valuable cargo space to have enough production from solar to do much with.

[Sunny Solar]

If his boat is already 12v and powering the motor I seriously doubt its drawing 200 amps. or the batteries be so big the boat will sink.

IF 2 x 100W panels are larger than the boat it cant be carrying a 1000 ahr battery..

[Sunny Solar]

Jon boats are available commercially between 8 and 24 feet (2.4 and 7.3 m) long and 32 to 60 inches (81 to 150 cm) wide, though custom sizes may be found...[COLOR="As the original post did not give the length of the boat it could be up to 20 ft and could easily carry 4x 100 w panels.
also many trolling motors have a max draw of 50a if that the case then 4 x 100 w panels would provide about 50% of the motors power and its also not likely to be running at full power all the time. mabe he will stop for some fishing and a joint to smoke while batteries recharging.#000000"][/COLOR]

[Sunny Solar]

2 x 100 w panels would take up an area of about 4ft x 3ft .if my calculations are correct that should fit on even a 8 ft boat.. will it would in Australia or Philippines but mabe not in USA??..
Recalculating this it seems that it would be possible to fit 4 x 100w panels on an 8ft boat.. and its very possible his boat is longer than 8ft..

[Sunny Solar]

SUNKIN you say you cant fit 2 x100w panels on a jon boat,then go on and say the 12v motor could draw 200A,.. Please tell us why the 2 panels wont fit on the boat but it can carry enough battery to provide the motor with 200a ??? HMMMMM I seriously doubt anyone would even contemplate a 12v 200a motor on a small boat..

Nice try but you didnt fool anyone with that .

[Sunny Solar]

any boat that is to small to fit 2 solar panels with a total area of 4ft x 3ft is FAR to small for a 1 to 3 hp 12v 80 to 200 amp draw.. If the panels as you say are bigger than the boat where do those very heavy 600 to 1000 ahr batteries go???
Most trolling motors draw a max 50 a and most times less about 30a so 2 panels of a 100w and 12 v would in most cases provide 14a thats about half the needed power so battery now only has to supply about 16a. if 4 panels used which WOULD FIT on any boat over 10ft long would supply just about ALL the motors requirements.And have room for a 200ahr battery.

Most boats used to carry even one person are bigger than 4ft x 3ft.. FACT.

[Sunking]

12 volt trolling motors use 1 amp/1-lb thrust.
12 volt Trolling Motors size range 30-lbs thrust at the low end, and 200-lbs on the high end. Pick your flavor of the day
100 watt 12 volt battery panels at best deliver 5 to 6 amps of current (Voc = 22 volts, Vmp = 17 volts, Imp = 5.8 amps, Isc = 6.2 amps)
12 volt Marine batteries run 60 AH on the low end up to 200 AH on the high end. Pick your flavor.
Those are the facts JohnP

[Sunny Solar]

Sunking the information in your last post we already knew .And I said the panels would produce 14a you say 12a. ok not much difference really.
What does make no sense is this...2 x 100 watt panels are larger than a Jon boat How can you possibly come up with this non fact..? 2panels of 100w cover an area about 4ft x 3ft..? Its more than likely that the boat as I already said many times but you ignore can have 4 x 100w panels and that would be enough to just about provide most of the power for the motor. Its certainly not going to keep the battery fully charged BUT it certainly will reduce dramatically the drain on the battery. AND IT IS NOT GOING TO SINK THE BOAT..

There is no amount of panels you can put on a Jon boat to do any meaningful work while afloat to charge your Marine Trolling motor battery. It would be silly to try and not to mention great possibility to sink your boat. Glup, Glup! It will take a panel the size of a house to recharge your battery in a single day.This is just moronic. And just another wild exaggeration you are prone to making.

If the person asking about if it a good idea to add panels to the boat to extend the range and to recharge the batteries when not in use if he has any sense whatsoever he would totally ignore your useless ramblings and obtain 2 or possibly 4 x100w panels and be very happy with the result. They will fit ok no problem on the boat provided its larger than your rubber duck you use in the bath by about 10ft..

[Sunking]

Where are you going to sit in that Jon Boat John? How are you going to orient the panels and deal with wind? You going to make a roof out of them and make the boat top heavy?

[inetdog]

Where are you going to sit in that Jon Boat John? How are you going to orient the panels and deal with wind? You going to make a roof out of them and make the boat top heavy?

Have you never heard of a solar sail?

For what it is worth, if you are using a trolling motor at less than full power, the current will be correspondingly reduced. But if it is the sole mover of the boat and you seriously trying to get somewhere, you will probably be at full power.