Thanks everybody for the replies
I guess the best decision would be to go with a gasoline outboard.
Since there is going to be no easy access to AC, recharging will be
available through the alternator only. Meaning the following flow of
energy: fuel - alternator - battery - motion with multiple
transition of energy back and forth from/to chemical (2 types),
electric (2 times), and motion (2 times) type forms. This cycle just
does not seem as efficient as a simple fuel - motion. Plus, the time
required to recharge---I don't think I'll have it. I'll start looking
for some 4-stroke outboard like Honda now.
Why not get a canoe & paddle?
This is a good idea. But, for a person who spends all most of the time
at his job just sitting on a chair this might too much of an exercise.
Plus, I want to have some energy left to build a camp/cook a descent
(hot) meal.