Posts: 433
Location: Cedarburg, Wisconsin | Tough question. The amount of energy you will need can only be determined by trial.
If you get a 24V system, then you will always have to have two batteries on board which is extra weight in a boat already short on horse power for the load. You will need to disconnect the batteries and charge them one at a time, or get a charger with two banks isolated from each other so you could charge them both at one time. Or buy a switch that reconfigures the batteries from series for running to parallel for charging with a 12V charger. Any way, more work and/or more expense. The advantage is that the 24V system is slightly more efficient and will let you move faster too. But if you run it wide open, you total run time may not be any longer than with a 12V setup.
The 12V system needs only a standard charger, but remember to disconnect your trolling motor from the battery when charging. If one battery doesn't have enough reserve to last the entire day, next time add a similar battery in parallel to double your reserve. You can still charge them both at the same time with the same charger, only it will take twice as long as you have twice as much energy to restore.
I'm pretty sure I saw graphs illustrating that the faster you go the quicker your batteries will deplete, so you will actually get more miles running at a slower speed with the same battery. If it were my rig, I'd get the 12V motor and hope one battery was enough. If not, I'd add another in parallel. |
