Lab performance testing of a small Banki-Michell hydraulic turbine for remote applications

Abstract

For decades, hydropower has been the most important renewable energy source in the world. The use of Banki-Michell turbine (B-M) in small hydropower constitutes an attractive solution for rural electrification in developing countries and off-grid applications. This robust turbine is easy to design and to construct and not expensive. A test bench (JLA 29) for remote applications was installed at the Aero-Thermo-Mechanics Department of the Brussels Polytechnic School of ULB to test this type of turbine. This paper aimed to present the efficiency results of the installed Banki-Michell turbine test bench for remote applications and these results helped to design a typical turbine adapted for remote sites such as the Ryamukona site located in Burundi. Two series of B-M turbine tests were carried out, by varying the flow rate using the turbine control valve opening placed inside the distributor and also by controlling the turbine speed using a Sinamics S 120 drive. The efficiency of the turbine varies between 40 and 60% for a flow range varying between 15 and 20% of the nominal flow. According to the tests made with a discharge above 20%, the efficiency of the turbine can reach easily 75 %. Based on this turbine efficiency, a typical B-M turbine of an electric power of 79.5 kWe turbine was designed for Ryamukona site which is a remote site located in Burundi.