"Looking for questions that have no answers", or. "A charging We might go!"

7

77monzaspyder

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"Looking for questions that have no answers", or. "A charging We might go!"

Greetings, one & all. I humbly come to you with a concept that, if it works, will increase my day on the water, while subtracting about 100 lbs of battery weight from my tin can.

If I take a 90 amp alternator, and spin it via a belt drive & a 1/2 hp electric motor,and hook it all that up to a Group 27 battery (810 CCA) & my 44lb trolling motor. Now as long as my amp draw from both motors is less than what my alt is making, would it charge up my battery?

Now before you all start giggling about a possible perpetual motion machine, Let me stop you there. I understand with part wear alone, that's impossible. All I'm trying to do is what a alternator does in a car, just transposed to my lil electric setup.

I know I might be in need of a good voltage regulator, or just use an alt with a built in regulator.

I thank you, one and all for your viewing of this post.

You may start throwing chairs now.
 
L

Lyle29464

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

The 1/2 HP motor will not do it. I am to tired to do the math but the size of the motor needed will draw about 120 % of the Alt output. If you forget the Alt you will lose about 15 lbs and your rig will go much farther on a charge.
 
Frank Acampora

Frank Acampora

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

You have me totally confused! Explain how it will save 100 pounds weight. How do you intend to power the motor? Where is the source?

Why not just buy a Honda generator for inside the boat? Too many unanswered questions.
 
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Chris1956

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

77, You have described the perpetual motion machine. Electric motors and generators are about 99% efficient. So your setup, if perfect will only cost you about 2% in losses. However, I do not know the efficiency of the Inverter you will need to use to run the AC motor.

So in a perfect world, a battery will be 2% more efficient. Does the reduction in weight justify that?
 
Silvertip

Silvertip

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90 amps x 12.6 volts = 1134 watts. That is the equivalent of a 2 hp motor if one considers 640 watts per hp. So explain again how you expect this scheme to work. Especially the part about where you intend to get power for the drive motor. And if you intend to use an inverter to drive an ac motor of 2 hp or even one half hp, there is a 10:1 power conversion factor you need to consider. To get 10 amps of 117 volts ac from an inverter you need to input 100 amps at 12.6 volts.
 
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steelespike

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

A 1/2 hp electric motor 12,24,36,? volt dc? or 120 volt AC? Anyway a 1/2 horse won't do it.
Did you ever notice when you turn on your headlights your motor takes a momentary dip?
And thats not even adding a full load.
Much simpler rig a solar charger. Would take a pretty big panel . I think $300 or $400 would at least get you enough to extend your range a little. And of course it would charge the battery if you stop and fish or what ever.
 
H

Home Cookin'

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

Hurry, springtime, before we all invent ourselves to death!
 
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tomhath

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

77monzaspyder said:
Now as long as my amp draw from both motors is less than what my alt is making, would it charge up my battery?
Click to expand...

I assume this is an early April Fools gag. But the answer is "Yes", if you could produce more energy from the alternator than you use to turn the alternator and the trolling motor this would work. But the laws of physics will be working against you.
 
Silvertip

Silvertip

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This reminds me of a teen age son helping his Dad move a 5 HP air compressor from the garage floor to the upstairs in the garage. Genius suggested making sure the compressor was at maximum pressure as it would be a lot lighter.
 
RogersJetboat454

RogersJetboat454

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

No such thing as a free lunch when it comes to energy.
Gravity, friction, and electrical resistance see to that. As stated, it takes far more than a 1/2hp motor to spin an alternator while under load.
 
Frank Acampora

Frank Acampora

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Oh! I get it now! You want to use one battery to power both the trolling motor and the electric motor to drive the alternator. AND--You expect the alternator to put back more watts than you take out--Perpetual motion, hell! You are not even looking for a free lunch. NO! You are looking for a miracle.

Last guy that did something like that did it with fish and bread.
 
MH Hawker

MH Hawker

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

Snickers :facepalm::lol: hurry up spring before the melt down hits. I would think one of those wind generator things would help but it would be hard to cast with one of those on a boat, or a raft the size of a Cadillac with solar cells. or tie the generator into a set of foot cranks :facepalm:
 
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Home Cookin'

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Re: "Looking for questions that have no answers", or. "A charging We might go!"

Re: "Looking for questions that have no answers", or. "A charging We might go!"

forget windmills--install underwater turbines to spin while you're moving and power the generator/alternator.

I'd give you details but I have to get back to that better mousetrap I'm working on....
 
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