Okay I know absolutely nothing about this but maybe someone here will have seen or heard about this...
The other day my wife was talking to someone about generating power on boats. This guy apparently told her about some sort of a generator
that, while moored, hangs in the water
and works off of the current
of the tide and slowly charges your batteries. I have heard of no such thing and cannot see how such a slow moving current
could possible create enough power to charge a battery
, let alone an entire bank.
This might be an option for recharging batteries while under sail though.