Installation of Bulb Turbines in Small Hydropower Plants : A Review

A large potential is available in the small hydropower schemes. There is a necessity to harness this potential to meet the increasing rate of energy demand. Due to the growing economy and population, demand of energy is increasing day by day. This increasing demand of electricity results in increase of tariff rate and the present energy crisis. Previously, sufficient attention was not paid to low head hydropower schemes due to higher cost. Now, to fill the gap between demand and supply of electricity, emphasis is laid on the development of low head sites. Several low head turbines are available these days, out of which, the bulb turbine is found to be the most suitable for such site conditions. Bulb turbine has a compact form and good hydraulic features, resulting in lower civil structure cost and hydraulic losses compared to other types of turbines employed under the similar site conditions. A lot of research work has been carried out to improve the cavitation properties, to develop a coating for blade tip protection due to sand erosion, investigation of bulb turbine characteristics during its operation in reversible regimes and to predict the dynamic behavior of the bulb turbine. In the present paper, an effort has been made to present a review of the technical and operational aspects of the bulb turbine