No one method of generation works in all cases. A wind generator is no use in sheltered places and not much good when going downwind. A towed water turbine is only any good when under way. Solar panels need a lot of space to give any useful charge and are not a lot of good in northern latitudes. A generator (diesel/petrol) requires a lot of space & is heavy, too much so for your size of boat.

I would suggest one of these. It is neither fish nor fowl so will not be as good as a dedicated wind generator but is likely to be a lot more uses e.g. on a tradewind passage.