Performance characteristics of the Energy Cat 3EC42 hydrokinetic turbine

Archimedean screw-type hydrokinetic turbine is a design from Jupiter Hydro Inc. that shows promising performance in water tunnel and field experiments. This paper reports on results of field experiments on their second prototype, Energy Cat 3EC42 turbine. Results show an increase in the maximum power coefficient of the screw turbine compared to the first prototype, Delta unit. An instantaneous maximum performance coefficient of 0.50 was obtained in Prony brake torque measurements. Surface roughness appears to increase the efficiency of screw type turbines. It is estimated from results of experiments done on these two prototypes that a screw-type turbine can reach a performance coefficient of 0.45.