I recently read this http://www.earthtechling.com/2011/0...ng+(EarthTechling)&utm_content=Google+Reader" and it's really bugging me. They claim that by putting wind turbines on the prow of the ship they'll harvest energy from the wind but also, that the air resistance will decrease and so the fuel consumption will be lowered. No doubt that the air hitting the boat will be less strong (because the wind turbines "trap" its energy) but what about the air hitting the windturbines? Aren't they just claiming this?: [PLAIN]http://input-image.info/physics-troll/1285635805554.jpg [Broken] My assumption had always been "if you put a wind turbine on a moving vehicle, the energy delivered by the wind turbine will always be less than the extra energy you need to move the vehicle bacause of the drag produced by the wind turbine". Am I wrong? All this leaving aside the fact that the air resistance is not that important in these vehicles I guess. It's the water resistance which matters, hence, the shape of the boat under and above the sea.