Currently have a 24v trolling motor that uses 2 12v batteries with a plug in on board charger. The boat will be docked in a location without shore power available. I'm looking for advice on the options for charging this system the fastest. The main motor doesn't get ran long enough for an alternator charger to be useful. Solar applications? Portable generator? Replace current system with a 24v lithium battery and take home at night to charge?