Solar Powered Pontoon Boat

A little history. I have been dabbling in solar for quite a few years. I have a solar powered door on the chicken coop that opens at dawn and closes 1 hour after dusk. It has been working for 6 years with one recent battery change. I have a 130w panel on a north south, east west tracker powering 4, 6v gc2 batteries in series hooked to a samlex 24v 2000w psw inverter , monitored by a bogart 2025. Backup power is a 6hp 4.4 kw single cylinder, 750 rpm diesel lister type engine that turns a 150amp, 24v truck alternator thru a balmar controller. It also spins a 7.5 KW gen head for other loads. Well I picked up an old (1995) 18' pontoon boat the other day with a 50 hp 2 cycle outboard. This boat was begging for a trolling motor. I picked up a 12v minn kota 30# trolling motor and rigged it up on the back of the boat to see what it would do. It would move the boat about 2 mph. I put on my inventors hat and went to work with a few ideas I had up my sleeve. I decided that I would use 2 trolling motors, one behind each log, to power the boat. I removed the top of the motors and rigged up some linear actuators for steering and also for power trim.



Comments

  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    I wired the motors in series so I could feed them with 24 volts. With the control heads removed, I ran the power to the motors thru a pwm motor controller rated at 1440 watts at 24v ( 60 amp). Motor amp checks revealed they required about 650 watts at 100% draw.

  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    I converted the folding bimini top to a framework for a solid top and a couple solar panels



  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    I have taken it out a few times just on batteries and with putting around and fishing I used about 35 amp hours in 4 hours. I have 4, 6v gc2 batteries mounted on the front of the pontoon


    The atv winch makes for a great anchor windlass!!
  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    my days of hot rod boating are long gone


  • BB.BB. Posts: 27,684Super Moderators admin
    I would be careful with running two 12 volt trolling motors in series when connected to a 24 volt battery bank... The motors may not share loading equally.

    Also, if (worst case) one motor tangles the prop in a net/rope/hits a sand bar/etc. and stalls, the current draw on that motor will dramatically increase and cause its voltage across the motor to drop. The other motor can see >>12 volts across it and overspeed/over current/or damage electronics (if present) in the motor.

    Not saying it will happen (I don't know anything about your motors/etc.)--Just a concern.

    -Bill "always looking for the downside" B.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • EstragonEstragon Posts: 2,607Registered Users ✭✭✭✭
    Interesting... I've been thinking of doing something similar if I can find a beater pontoon boat with good tubes and ok structure. I assume you're keeping the 50hp O/B and checking to be sure it starts regularly. You wouldn't want to count on the trolling motors to keep you off a lee shore in a squall.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • littleharbor2littleharbor2 Posts: 979Solar Expert ✭✭✭✭
    edited July 14 #8
    squarebob said:
    my days of hot rod boating are long gone


    Pretty sure nobodies going to confuse a pontoon boat powered by trolling motors with a hot rod boat. lol
     Had a customer buy some panels from me to build a personal sized pontoon boat which was powered purely from the solar panels, no batteries. He had a joystick setup to control power for steering. It turned out pretty cool. Of course the overhead solar array provided him shade as well.
     Fun idea, keep playing with it.

    I don't suppose that's you in this picture.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • NANOcontrolNANOcontrol Posts: 58Registered Users ✭✭
    I made a 1937 GarWood electric many years ago. Been wanting to build an electric launch with only a small battery and using a linear current booster to provide maximum power real time.
  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    edited July 14 #10
    NO, that wasn't me in the picture! I have completed the installation of 2, 360 watt, 72 cell panels on the roof. Wired them in series to a midnight solar KID controller with a Whiz Bang added to it.






  • jonrjonr Posts: 1,029Solar Expert ✭✭✭✭
    I wonder if with independent power and forward/reverse, you could do away with the steering control.
  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    Estragon said:
    Interesting... I've been thinking of doing something similar if I can find a beater pontoon boat with good tubes and ok structure. I assume you're keeping the 50hp O/B and checking to be sure it starts regularly. You wouldn't want to count on the trolling motors to keep you off a lee shore in a squall.
    Need the O/B to get the bugger on and off the trailer. The ramp I normally use is very shallow and I have to get the car pretty far into the water and really "givver the beans" to unload and load.   
  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    edited July 19 #13
    jonr said:
    I wonder if with independent power and forward/reverse, you could do away with the steering control.
    That is a great idea. I have forward/reverse now. They are 12v motors and I have them in series to draw from the 24v battery bank. I wonder if I feed them independently with 24 volts but limit the amps if it would work out and not destroy the motors?
  • BB.BB. Posts: 27,684Super Moderators admin
    Many times, controlling the current to motors is actually better than controlling the voltage (assuming you do not over voltage at some point).

    Using a switch mode buck power controller set for current mode should would work fine (need to control the controller...).

    Of course depends on the motors (brushed, Permanent Magnet poly phase + own controller)...

    Might be an interseting place to start (no nothing about website or products):

    https://www.robotshop.com/en/brushed-motor-controllers.html

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • squarebobsquarebob Posts: 25Registered Users ✭✭✭
    I am running the motors now thru a pwm controller so I was thinking I can dial back the controller to have the same wattage going to the motors on 24 volt as they draw on 12 volt. A motor on 12v  at WOT draws 28.5 amps or about 350 watts. If i feed ~ 350 watts at 24v the motors should be OK?  I could pick up another controller, one for each motor and be able to eliminate the steering by using motor speed and forward/reverse as suggested by jonr. Here is the controller I am using.

    DC Motor Speed Governor (10V- 55V) 60A 3000W Forward/Reverse Switch Digital speed scale 0-100%







Sign In or Register to comment.