Please send your full manuscript to:
Abstract— Hydropower is one of the best renewable energy sources in Indonesia, because they (hydro and micro-hydro) have large potential resources and suitable with water zone topology of a country with many river and similar water source. However, the percentage of installations Hydropower in Indonesia is 11.95% which is quite large considering overall value of investment. To optimize the water resources, development is needed in terms of hydro-electric power, which one of the well alternatives is the development of the water turbine rotor design. This study aims to determine the effect of adding stages on the performance of the savonius water turbine on the horizontal axis. The research subject will use a one-stage rotor that will be modified into two-stage. Variations in the shift angle are applied at angle of 900 and the speed of water is 0.8 m/s and at TSR interval of 0.4-0.9. Simulation using Transient Blade Row type analysis. Calculation of the research was carried out using computational fluid dynamic technique of the ANSYS codes in which the interacting fluid flow and turbine structure are explicitly modelled. Results data presents torque distribution, velocity streamline, and coefficient of power (Cp). The tendency indicated that Cp was achieved in Savonius with the modified double-stage rotors. This configuration is suitable for urban water source, such as sewage water pipes, which is capable to optimally utilize the flow of waste water as a new energy resource. Furthermore, the emissions level due to machine combustion using fossil resources can be reduced.