Why does a glider wing have an efficiency of 99% (and foil 90%) and a marine propeller have much less? Traditional Propeller design has lot of constraints linked to the engine rpm, the materials and the space available.By loosening these constraints higher efficiency can be achieved in both propulsion and regeneration.This propeller, designed with a biomimetic approach, with a low Reynolds number, low apical turbulence and a high stall incidence, is able to maintain high efficiency in a wide range of conditions while always maintaining a laminar flow.

The experimental campaign has been carried out at the Institute of Marine Engineering (INM C.N.R.) Towing Tank allowed to optimize the Sail-pod efficiency in all operating conditions: propulsion and generation mode, as well when the propeller is closed in pure sailing mode to minimize drag.