Seeking Advice - Solar Powered Trolling Motor

[GreatVegetable]

Hello,


GreatVegetable here, new to the forum.


I recently purchased an old 17' canoe and am currently in the process of setting it up with a Minn Kota Endura C2 55lb thrust trolling motor and I am seeking a bit of advice on setting things up safely and properly.

I have the Minn Kota Trolling Motor Power Center, and I am planning to power the motor with a Duralast Group 27 Deep Cycle Marine Battery or something similar.

For a charger I want to use a POWISER 3.3W / 12v Solar Battery Charger/Maintainer.

The panel comes pre wired and is hooked to the power center using alligator clamps to the battery leads and can also be converted to use a 12V DC car inverter instead. This panel does not use a charge controller but is designed to not overcharge the battery.

The power center box has the external battery leads and two 12v DC car inverter outlets, so my first question is, can I charge the battery effectively using the 12v DC inverter or would it be best to use the alligator clamps on the external leads?

My second question is, can I have the solar charger and the trolling motor hooked to the same leads at the same time, and use the charger to maintain battery power while using the trolling motor?


Any advice would be greatly appreciated.


Thanks,

GreatVegetable
Edit

 

[GA_Boater]

Even the folks on THT will tell you you're trying to invent perpetual motion. Clean up when you cut and paste.

 

[gm280]

Okay, where to start? A 3.3 watt max output solar panel setup is only going to supply a mere 367 milliamps (.367 amps) of current, at best! The instant you turn on the trolling motor, that is gone. So unless you allow the solar panel to charge all day long and not use the trolling motor, it isn't going to recharge whatever you used out of it. That would take days of good sunlight charging. JMHO

You either need a lot more solar panel and a smaller TM or charge the battery via shore power. Those are the honest facts...

 

[mike_i]

I agree 100%, plus the panel would not be set to the proper angle for max charging. And if it were the charge current would be negotiable.

Okay, where to start? A 3.3 watt max output solar panel setup is only going to supply a mere 367 milliamps (.367 amps) of current, at best! The instant you turn on the trolling motor, that is gone. So unless you allow the solar panel to charge all day long and not use the trolling motor, it isn't going to recharge whatever you used out of it. That would take days of good sunlight charging. JMHO

You either need a lot more solar panel and a smaller TM or charge the battery via shore power. Those are the honest facts...

 

[GreatVegetable]

Okay, where to start? A 3.3 watt max output solar panel setup is only going to supply a mere 367 milliamps (.367 amps) of current, at best! The instant you turn on the trolling motor, that is gone. So unless you allow the solar panel to charge all day long and not use the trolling motor, it isn't going to recharge whatever you used out of it. That would take days of good sunlight charging. JMHO

You either need a lot more solar panel and a smaller TM or charge the battery via shore power. Those are the honest facts...

Okay thank you I didn't realize how underpowered this panel was compared to what I wanted to apply it to.
I originally planned on getting a HQST 100 Watt 12v Panel but wasnt able and opted for the other panel for the time being.
[h=1][/h]

 

[GreatVegetable]

Even the folks on THT will tell you you're trying to invent perpetual motion. Clean up when you cut and paste.

I'm sorry I'm not sure I fully understand what you are trying to say.
If I broke a forum rule or something I apologize.

 

[emoney]

Sadly they've yet to invent the Solar Powered Trolling Motor. If they had, the battery folks would be out of business, lol. Something to add that you may not know, but the "Speed setting" on your trolling motor should also have a label saying "battery drainer". The faster you run the motor, the quicker the battery begins to lose charge. Just something to keep in mind. Everybody should own a good, "smart" battery charger, even if you don't own a boat.

 

[Starcraft5834]

buy a 2.5 hp 4 stroke Merc and stick it on the back. weighs less than a deep cell battery, n will move you along much faster than going " green"...

 

[biglurr54]

I looked into doing this on a small pontoon. My figures set me at 3 100w panels and 2x 110ah batteries. This would allow me to run the boat at half speed for about 4-5 hours and then it would need about toa day to recharge. So your looking at about $1000 in solar and batteries. Then you have the electric motor cost. You can scale that down for a canoe but a 55lb motor burns 20amps /hour at half throttle. So the numbers will work the same. The difference would be the speed.

 

[GA_Boater]

I'm sorry I'm not sure I fully understand what you are trying to say.
If I broke a forum rule or something I apologize.

The link in your first post under your name at the very end of the post.

GreatVegetable
Edit

 

[H20Rat]

Also keep in mind that the moment you slap a motor, even an electric trolling motor, on that canoe, it now becomes a 'motorboat'. You will most likely need to register it, and because it is over 16 ft, you also have some additional requirements to follow. (may vary by state, so consult your state laws)

I removed the electric trolling motor on my sailboat for exactly that reason.

 

[Scott Danforth]

your 55# thrust TM will draw about 80 amps. at 12 volts that is 960 watts, assuming that you have no inefficiencies......

a 3 watt solar panel is used to keep the battery from going dead (maintained) because the clock is on in a car and they barely do that.

so your idea to use solar to power the boat would require an array of solar panels about 3-4 times the size of the boat. yes, an active array of panels about 20 feet long and about 10 feet wide and a bunch of batteries

since solar panels need to be aimed at the sun to be efficient, how do you plan on doing that in a canoe that is bouncing up and down in the waves?

buy a 2-3hp outboard designed for canoes and you will not only be about 100x cheaper than spending thousands on the solar array, it wont weigh anywhere as much as the TM or the battery or the 500# of solar panels and wiring......and most importantly...... it will actually work when it gets cloudy.

 

[Starcraft5834]

your 55# thrust TM will draw about 80 amps. at 12 volts that is 960 watts, assuming that you have no inefficiencies......

a 3 watt solar panel is used to keep the battery from going dead (maintained) because the clock is on in a car and they barely do that.

so your idea to use solar to power the boat would require an array of solar panels about 3-4 times the size of the boat. yes, an active array of panels about 20 feet long and about 10 feet wide and a bunch of batteries

since solar panels need to be aimed at the sun to be efficient, how do you plan on doing that in a canoe that is bouncing up and down in the waves?

buy a 2-3hp outboard designed for canoes and you will not only be about 100x cheaper than spending thousands on the solar array, it wont weigh anywhere as much as the TM or the battery or the 500# of solar panels and wiring......and most importantly...... it will actually work when it gets cloudy.

^^^^^--smart guy i agree... tried the electric 55lb thing years ago on a 8ft Sundolphin plastic boat! LOL.. immediately realized after 1 outing, that was a bad idea. the 2.5 4 stroke merc outboard i bought produces 2-3X power, has gas tank on top of the motor and weighs 40lbs... have a new 20ft toon now, it sits next to the 115, when i need it on hp restricted lakes it pushes that near 4mph on cloudy days! LOL cloudy day comment,, loved that one....

 

[jebby]

not even in the ballpark. might want to check your math. i'd expect 100W minimum with a charge controller. the cost of the motor, the battery, the solar setup just buy a small outboard.

 

[GreatVegetable]

Well thanks for all the responses everyone and for shedding some light on the flaws of my setup.
I now understand a bit better and did some homework on how to make this setup a bit more practical, I still intend on making this work.
Also if I were to elaborate on how I plan to apply this setup it would seem more practical I guess.
I dont intend on using it for an entire day on the water, I simply want to use it to travel about 1.5 to 2 miles across a relatively calm lake, to a place I like to camp and is only accessible via boat.
After doing the math I should be able to make a 100ah battery last 4 hours using 30#s of thrust, which is more than enough time to get to my destination.
Once at my destination I will setup my solar panel (obviously not going to be using the 3.3w panel) in a good spot and let it charge back up.
I usually spend at least 2 days when I'm out camping/fishing so this leaves me one whole day to let my battery recharge.
I think I will start with a 100w panel and see what that does for me and go from there.
I am aware that I will have to get the boat registered and had already planned on doing so.
As for buying a 4 stroke outboard, I'm just generally not interested, I think I can make the trolling motor work, even if the solar charging doesn't work as efficiently as I'd hoped, I think I can make due and worse case I paddle out the last half mile or so if my battery dies, no big deal that's how I'm used to doing it anyways.

Again, thanks for all the responses, really do appreciate it!

 

[racerone]

I believe 1 HP + 746 Watts--------3.3 watts would barely be equal to a hamster running in one of those exercise barrels.

 

[Scott Danforth]

Well thanks for all the responses everyone and for shedding some light on the flaws of my setup.
I now understand a bit better and did some homework on how to make this setup a bit more practical, I still intend on making this work.
Also if I were to elaborate on how I plan to apply this setup it would seem more practical I guess.
I dont intend on using it for an entire day on the water, I simply want to use it to travel about 1.5 to 2 miles across a relatively calm lake, to a place I like to camp and is only accessible via boat.
After doing the math I should be able to make a 100ah battery last 4 hours using 30#s of thrust, which is more than enough time to get to my destination.
Once at my destination I will setup my solar panel (obviously not going to be using the 3.3w panel) in a good spot and let it charge back up.
I usually spend at least 2 days when I'm out camping/fishing so this leaves me one whole day to let my battery recharge.
I think I will start with a 100w panel and see what that does for me and go from there.
I am aware that I will have to get the boat registered and had already planned on doing so.
As for buying a 4 stroke outboard, I'm just generally not interested, I think I can make the trolling motor work, even if the solar charging doesn't work as efficiently as I'd hoped, I think I can make due and worse case I paddle out the last half mile or so if my battery dies, no big deal that's how I'm used to doing it anyways.

Again, thanks for all the responses, really do appreciate it!

did you take into account wind load? personal experience has a 17 foot bass boat going thru two group 27 batteries in less than 1/2 mile against the wind, and with the current with a 55# minn kota

a 100watt panel wont do much. I know many people that live on sail boats and house boats. the houseboats have about 15 300 watt panels on the roof and a charge controller to keep the batteries charged for just lights. For other house loads there is a dedicated generator.

my buddy who lived on his 37 foot sail boat for almost 22 years had 6 300 watt panels on his boat for when he goes down to the Bahamas and Exumas to keep party lights going as well as the LED saloon lights..... along with a wind generator (car alternator with a propeller) the 6 panels produced an average of 85 watts each on the boat with the boat moving up and down with the swells. so instead of 1800 watts of charge power, he was getting closer to 500 watts, and that was on a clear sunny day in the south. where the wind generator was putting out about 35 amps most of the time (however the noise will drive you nuts) the hassle of aiming the panels was too much, so the last storm he hit in the atlantic that had broken the panel mounts and had the panels hanging over the side banging into the hull, he simply cut the cables and let them drop.....

so assume your 100 watt panel would give you about 30-35 watts of usable power

 

[gm280]

Always do the math. If it doesn't work out doing the math, it isn't going to work out in reality...period!

 

[jebby]

if that's the case just buy a big enough battery to give you the run time you need. not going to lose much to parasitic draw over 2 days

 

[biglurr54]

I would buy at least two batteries. You could get out there and then be stuck. Plus these batteries should never be drawn down below 50% capacity. Anytime they go below 50% capacity, you drastically shorten their life. And at $200 a battery, I want to preserve the battery as much as possible. I think 2 100ah batteries and a 100w panel will be a good place to start for a canoe. The two batteries will get you home in an emergency (drawn down below 50% but its an emergency) and the 100w panel will provide a good amount of juice. I run my whole house off an array the size people are mentioning here. Its 10kw array. Ive seen many boats powered by much much smaller arrays. Theres a boat locally that is solar powered. (goole Solaris Solar Boat) I think 3 100w panels and you could sail around on sunny days all you want but you need a battery as a buffer and you need to make sure you never drop below 50% charge when there is no sun.

I agree that small canoe outboards are much better and they will most likely be cheaper in the long run.