SIHG Testing and Analysis

This paper describes the Sailboat Integrated Hydroelectric Generator (SIHG). This turbine is intended to be fixed to the transom of a 30–40 foot sailing vessel to produce green power for the vessel’s electrical systems. The design goal for the SIHG was the generation of a minimum of 225 watts at 6 knots and an ideal output of 400 watts at 6 knots. Power is generated by the SIHG when water moving over five turbine blades creates rotational motion, which is transferred through a gear box to a three-phase electrical generator. The three-phase electrical output is then rectified and used to recharge the boat’s battery. Presently, most sailboats of this size run their engines in order to recharge their batteries. The SIHG produces no emissions and has no operating costs. Extensive testing in the Thames River at the U.S. Coast Guard Academy in New London Connecticut produced data that was then used to determine the power output and efficiency of the SIHG at various speeds through the water. The turbine was fixed to the transom of a dinghy which was then towed behind a rigid hulled inflatable vessel to simulate a sailboat under wind power. Novel data collection methods and instrumentation were then used to gather power and drag data for the turbine at various speeds. Power output plots and efficiency curves were calculated from this data and are represented in this paper. Actual performance shows that the SIHG is capable of producing 275 watts at 6 knots and 400 watts at 8 knots. The maximum efficiency of the SIHG is calculated to be 37% and occurs when traveling through the water at a speed of 5 knots. Due to the substantial power generation at relatively low speeds, tidal applications are discussed.