Solar for kayak - Kayak Fishing Adventures on Big Water’s Edge

PescadorPete · 11-03-2013, 04:06 PM

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.

old_rookie · 11-04-2013, 07:58 AM

Quote:

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 · 11-04-2013, 08:56 AM

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 · 11-04-2013, 07:34 PM

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

11-04-2013, 07:34 PM	#4
FISH11 Member Join Date: Aug 2013 Location: Pine Valley when not fishing La Jolla Posts: 2,643	solar power 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

11-03-2013, 04:06 PM	#1
PescadorPete Senior Member Join Date: Mar 2005 Location: Leucadia, CA Posts: 261	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.

11-04-2013, 08:56 AM	#3
steveooo Senior Member Join Date: Sep 2005 Posts: 1,922	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.