Solar for kayak

[Yakly]

Thanks guys for the info.... I think I'll take the advise from you guys and purchase LiFePO's. You guys have been doing this for some time so ill follow your leads.... It was just a thought as I'm into gadgets but understand the limited space.

I'm also one of those crazies (in the eyes of some) that want to do an extended trip up the coast and camp. So if there's anyone interested or if they're trips already planned, I'm in.

[jruiz]

Originally Posted by alanw

That just doesn't sound right according to Ohm's Law.

V = I * R

Voltage = Current * Resistance


The resistance of the motor is a constant, so the only things that can change is volts and current which means that as voltage goes down so does current.

That means that a 6 volt 10 amp battery should last longer than a 12 volt 10 amp battery.

Motors aren't resistors.

[Old Man in the Sea]

This is the charging system I would recommend to meet all of your charging needs

http://www.globalindustrial.com/p/ou...FSFyQgodZgIABA


only downside is that it requires an additional kayak to be towed behind you...

[alanw]

Originally Posted by jruiz

Motors aren't resistors.

Right, motors are inductive, but the load can be considered resistive

[FishNinjaY]

Originally Posted by Yakly

It was just a thought as I'm into gadgets but understand the limited space.

I'm also one of those crazies (in the eyes of some) that want to do an extended trip up the coast and camp. So if there's anyone interested or if they're trips already planned, I'm in.

I hear that.. we're all gadget heads.

If you want to think outside the box... why don't you get rid of the battery altogether? at least for the livewell.

I know there is a small-ish solar panel that can run an actual small pump that will take water from your swimming pool and pump in UP to to a gravity solar array on your roof for pool heating. The nice thing about that, is it is ALWAYS ON, and only runs when the sun is out. Perfect for people that like to run their pool filters during the night to save on electricity costs. Anyways, I bet that solar panel and pump have to be sufficient to run any kind of livewell bait tank, right? If it puts out enough juice, maybe you can even run your fishfinder also? or at least keep a FF battery topped off.

[Yakly]

I'm still looking at all kinds of options and trying to wait till the new boats come out to see what new goodies will be available. Sometimes it sucks wanting all of the new shiny stuff..... My girlfriend says I have ADD but whatever, it keeps me busy and out of trouble...... So far!!!!

[jorluivil]

"The best solution to our problems may actually be the nearest or the easiest. Sometimes it seems so easy that we doubt its effectiveness"

[PattiNorton]

Originally Posted by Yakly

Anyone currently using solar panels of any sorts on their yaks to keep the battery charged? Been thinking and researching different panels ( some small enough) to keep the live well and chartplotter charged for a full day. Any suggestions or comments????

Hello friend have you got the solar panels or charger? I am trying to use solar energy for charging battery so please help me with your experience..Waiting for reply thanks in advance

[taggermike]

I'm with the get a bigger battery side and make sure you put it on the charger the night before you fish. I have thought of a solar charge set for Baja trips where you don't have access to power but plenty of sun. Bring 2 batteries and alternate them. Mike

[PescadorPete]

Here battery voltage versus current with a Hobie 12v bait tank pump, tank full of water:

12V --> 1.37A
11V --> 1.20A
10V --> 1.06A
9V --> 0.91A
8V --> 0.77A
7V --> 0.64A
6V --> 0.52A
5V --> 0.39A

On six volts, the pumps draws less current (so it uses less power) than at twelve volts. My experience has been a 6 volt battery last much longer that a 12 volt battery powering the pump.

[Fiskadoro]

The traditional problem with solar for a Kayak is the size of the panel you need to put out the power required.

For instance I have a mono-crystalline solar panel for my truck to keep the battery up when I'm not using it. It's about the size of a piece of paper and only weighs a few pounds but it also only puts out 5w or .28amps.

It would charge a battery that's sitting but won't keep up with a fishfinder and bait tank.

A 50w mono-crystalline panel would put out 2.8 amps. That would be enough power to run a Hummingbird combo and a Hobie baittank but it would be roughly 2 ft square and weigh over 20 pounds.

More realistic would be a poly-crystalline 50w panel. Once again that's only 2.8 amps but I've seen some of those that were only like 12 pounds but they were still big something like 20x30 inches.

Pete you got me rethinking this though. I think most of the newer Hummingbird finders only pull half an amp. Having a variable voltage setup where you can step down to a 6v for the bait tank and that would pull less amperage about the same half an amp. 1.5 amps would probably do it.

I have several friends who are into bike touring and they are using combinations of 5w panels to make 20w and 25w systems for charging phones lights GPS etc...

I'll look around and see what I can find.

Jim

[PescadorPete]

Jim, it will be interesting to see what you come up with. Maybe a 12V panel to feed the ff directly and also feed the 12V to a PWM to power the pump. I built a PWM for my 1st bait tank setup and the 12V battery lasts almost as long as running the pump on a 6V battery. I didn't measure how low the 12V battery can go before the PWM quits. pete

[old_rookie]

Originally Posted by PescadorPete

Here battery voltage versus current with a Hobie 12v bait tank pump, tank full of water:

12V --> 1.37A
11V --> 1.20A
10V --> 1.06A
9V --> 0.91A
8V --> 0.77A
7V --> 0.64A
6V --> 0.52A
5V --> 0.39A

On six volts, the pumps draws less current (so it uses less power) than at twelve volts. My experience has been a 6 volt battery last much longer that a 12 volt battery powering the pump.

I bet the motor/pump moves less water too. If the amount of water circulated is adequate, then it sounds like a good solution. But this idea doesn't work for other electronics such as FF or whatever that needs to run on 12V. Usually they have internal voltage converters to bring it down to 5VDC for the internal electronics run - but there could be other devices that still need 12VDC - like the display or sonar. So it is best to run those at the rated voltage.

[steveooo]

Solar on the kayak definitely wouldn't be my cup of tea, but the technology is available...

Hobie has a foldable 23W Solar panel for the eVolve that kicks out enough juice to run the motor and push the kayak at about 2 knots indefinitely in sunny conditions. It weighs only 1.4 lbs and is designed to withstand getting wet with saltwater. With a few mods, I bet that could run a fishfinder or 2.

On our Santa Cruz camping trip, I was able to run my Garmin for 3 days off the same 12V 12aH LiFePO3 battery the entire trip without needing a charge. For an extended trip I think my preference would be to just bring a 2nd battery and KISS.

[FISH11]

I just added a small solar panel 1.5 watts that Harbor Freight sell. They have it now on line, on sale for $15.99. It is not a permanent mount as I can put it on the back of the crate and it's the same width as the crate. That way it is very compact and it's just to supplement and help the battery last longer. I run my fish finder and my livewell both off the 12v 10ah battery. I have a timer on the livewell line and it's set for 12 seconds on and 20 seconds off. It will run for 10 hours and only drop battery voltage from 13 volts at the start to 11.8 volts at the end of 10 hours. I don't use the panel regularly but got it, for if I go away to a place without electricity for several days. Then I can help reduce the voltage drop or to charge the battery on the second day while using a back up battery. It doesn't weigh hardly anything and it sure was cheap. They have some with more power but are much larger. I use die electric grease on all the connectors and keep it inside the hatch until I need it so as not to expose it all to the surf at La Jolla. It only took a short bungee cord on each end to secure the 2 ends. It also came with suction cups to secure to inside a windshield and with 2 connectors a cigaret adaptor and 1 with clamps for straight to a battery. Hope that helps anyone. Mark