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.

The world is facing a severe shortage of adequate and secure supply of energy on the one hand and environmental-related problems arising due to excessive consumption of energy on the other hand. On an average, there is about 1.6% annual rate of increase in global primary energy demand. The increase in global energy-related carbon dioxide (CO₂) emissions is estimated to be 55% for the period 2004-2030 (International Energy Agency, 2006).

This scenario emphasizes the need to take immediate action to steer the energy system onto a more sustainable path. New policies and measures should be enforced to enhance the energy security and mitigate CO₂ emissions. These measures include efforts to improve efficiency in energy production and use, and to increase reliance on non-fossil fuel energy that is clean and green, such as hydropower, wind, solar and bio energy.

Hydropower is in abundance, and it has a self-renewing supply, conserves our fossil fuel reserves, does not cause pollution and produces no waste streams. Hydropower has the highest operating efficiency of all known generation systems. They are largely automated, and their operating costs are relatively low. Hydropower plants also play an important role in water resource management, in preventing floods and making rivers navigable, solving irrigation problems and creating recreation areas (http://www.voithhydro.com/vs_e_grpdivaboutvsh.htm). Several disadvantages are also associated with large hydropower. Due to large hydropower, there is a large displacement of population and a vast area is submerged in the reservoir. Heavy deforestation and change in ecology have a major impact on society and environment.

Small hydropower is free from all the drawbacks of large hydropower. It is reliable, eco-friendly and involves a mature and proven technology. It is non-polluting, involves low operation and maintenance costs and involves no cost for fuel. India is blessed with many rivers and mountains, offering tremendous hydropower potential. Contribution of small hydropower has grown substantially in the last ten years. Presently, in India, the total identified potential is around 10,265 MW. But, we are harnessing 1,630 MW with the help of 505 sites. Further, 161 projects are under construction having a capacity of 539 MW. The target capacity addition by 2012 is 2,000 MW (AHEC, 2004).

Mechanical Engineering Journal, Bulb Turbines, Hydropower Plants, Water Resource Management, Hydropower, Hydropower Schemes, Musical Instruments, Mathematical Models, Hydroelectric Projects, Computational Fluid Dynamics, Mechanical Validations, Finite Element Analysis.