Sustainable energy...

[koi]

Hello all,

So, i am trying to figure out... How can i push a 70+ foot wooden sailboat through the water without an engine; for harbors, canals and such. Is the most efficient way of moving a boat under human power really with oars? Does anyone out there know of any plans or ideas for building a human powered gear driven propeller system? I'm no mechanical engineer, so i'm left with a few questions if anyone out there can help, or knows someone who can.
How do i determine the amount of force necessary to push a vessel through the water, and...
Is it conceivable that the necessary force can be generated with a geared contraption similar to a rowing machine, built for four or six persons. If not human powered, any other non internal combustion solutions with low energy requirements? That's all for now... thanks, - Brandon Lovejoy

Koi,

Are oars the most efficient? How about a propeller mounted on a chain/spoke set up (ie as a bicycle powered bike)? Some models are available commercially for recreational purposes?

Also be aware that a 70 ft boat is a large expense. And it has probably a large fetch associated w/ it. One wrong wind direction, it could overcompensate for the 2hp a person can output and the boat could in effect be in on the rocks.

JMHO

DeepTuna

How about batteries. You could charge them with a bicycle type device (or other human powered device) as well as the with a windmill generator. That would give a fair amount of power for at least short periods, no?

[Scott]

I'm not sure if the idea is to create something 'historic' (i.e. to build a boat which could have existed in a time period before engines and motors) or to create something which is environmentally friendly. Both are neat projects.

I would tend to think that batteries and an electric motor would be the best solution, allowing you to store up energy and use it when things might be frantic, i.e. maneuvering into a difficult docking situation or to prevent going aground. Plus you can take advantage of wind and/or solar to build up the power. For curiosity, if it were supplemented with human power, I wonder how efficient the generator can be (how much effort/power is lost in the double conversion vs. a direct human drive?)