Energy Observer has also been fitted with two Oceanwings to further enhance her energy saving abilities; a change which turned her overnight from a purely power driven vessel to a kind of motor sailor, even though the surface of each automatic wing is only 30m2. It was also obvious to the team running the project that fitting propellers more suited to a motor sailing vessel would offer considerable further improvements, increasing the vessels speed by reducing propeller drag when sailing and optimising hydro-generation.
Autoprop Eco*Stars work by using their unique auto pitching abilities to match the constant torque that the electric motors provide throughout their rev range. This ensures that the craft is always obtaining the most efficient propulsion in terms of propulsive energy and economy and both at the same time. When purely sailing, and if maximum speed is not essential, the Eco*Stars can be left to turn in the vessels wake providing additional charging for the batteries.