Solar Pontoon boat

[Alabama Mike]

I have a few questions concerning a project I am currently working on, I'm still in the early stages and i'll be honest not truly sure what I'm doing, LOL. I live on a rather large lake here in alabama, At the start of the summer we had a pedal boat that I added an old 10 lbs thrust trolling motor too, and then later built a roof and added a 45 watt harbor freight solar panel kit, on a sunny we could run the boat without a battery in it, which was fun in knowing that we could run on "sun Power".

Well now I wanna step up my experiment, I have an old 24 foot pontoon boat, and was recently gifted an electric motor Its a ME0708 Montenergy, http://www.motenergy.com/me0708.html, I am either gonna use a Glen L design on the drive http://www.glen-l.com/designs/specia...tricdrive.html, mount the motor on an old 25 HP johnson (I have access to the outboard with a bad powerhead) or attempt to do an inboard set up. The motor can be ran at 12, 24, 36 or 48 volts, I'm still undecided on the exact voltage I need to use it at. I do plan on a battery pack, and a pwm controller.

I'm not sure how the solar panels work, can they be run is series and parallel just like a battery can be? I'm wanting to be able to actually run this motor on solar power alone? is that possible at these voltages? The motor says its rated at 100 amps continuous and up 300 amps for one minute, so My thinking is the 300 amps is a spike when the motor starts? and the 100 amps is wide open running speed? How do I figure what watt amount of solar panels I would need?

Now to some of you these might sound like dumb questions, But I hate to say it messing with Electricity is way out of my knowledge range, I'm good with automotive style electronics there basicly all 12 volts.

Any and all help will be greatly appreciated.

Mike

[Mike90250]

Hi, welcome.
Solar panels can be "stacked" both series or parallel. They just need to be the same kind of panels, voltage and amps matched within 5-10%. If you buy 4 panels from a vendor, they will already have been factory sorted and labeled.

But this is the sort of thing you should design first, then purchase. You "could" run the motor right off the panels, but if it clouded up, you would be stuck.

[Alabama Mike]

I understand if I run the panels on a cloudy day it wouldn't work, thats why I will have a battery bank. but how do you figure the amount needed, I've been told if I run it in 24 volts, that I would need 2400 watts at 24 volts, then later I was told I have to have more voltage than the actual system I am using, roughly 36 volts at the panels using a charger controller to to charger the batteries. so if I go with more voltage does that mean less watts?

[Mike90250]

I understand if I run the panels on a cloudy day it wouldn't work, thats why I will have a battery bank. but how do you figure the amount needed, I've been told if I run it in 24 volts, that I would need 2400 watts at 24 volts, then later I was told I have to have more voltage than the actual system I am using, roughly 36 volts at the panels using a charger controller to to charger the batteries. so if I go with more voltage does that mean less watts?

So this is getting complex. You want a way to get back home on a cloudy day, so that means you need to know how many watts your motor consumes at your typical speed, and how many hours you need to run at that speed.
Watts x Hours = Watt Hours. Then we can see what size battery that requires.

[Alabama Mike]

So this is getting complex. You want a way to get back home on a cloudy day, so that means you need to know how many watts your motor consumes at your typical speed, and how many hours you need to run at that speed.
Watts x Hours = Watt Hours. Then we can see what size battery that requires.

well the motor is rated in amps, not watts. The website says 300 amps peak for 1 minute and 100 amps continuous, I'm figuring the 100 amps is at full power, From the way I am understanding it the amps will be the same regardless of what voltage I am running the motor at. I understand the battery requirement, I'm thinking 4, 100 amp hour, deep cycle batteries, wired to run 24 volts. the motor will be run off the batteries, and the panels will be recharging them. But I have read that 2400 watt/24 volt panels will not recharge my batteries, that I would have to run a greater voltage and then run it thru a charge controller. I would like enough power to make a 3 or 4 hour trip, 2 or 3 times a week. I'm looking into a 24 volt generator (for a just in case situation). I guess I am having problems grasping the whole volts/watts/amps thing.

[Mike90250]

well the motor is rated in amps, not watts. The website says 300 amps peak for 1 minute and 100 amps continuous, I'm figuring the 100 amps is at full power,......

Still, to size it to a battery you have to convert to watts and measure the watt hours.
100A at 24V is half as much wattage as 100A at 48V.

So you have to pick what voltage you want to run at, and run the numbers. Use a spreadsheet for this stuff