Optimization of the Internal Hydraulic and of System Design in Pumps as turbines with Field Implementation and Evaluation

The research on ‘pumps as turbines ’ at this critical phase of developing decentralized small hydro systems is appropriate for many reasons. The conventional turbine technologies like pelton and cross flow turbines that have been implemented in the micro hydro sector have to be custom-made and are therefore more expensive. They also need expert design and precise manufacturing skills for a good performance. This often becomes a bottleneck especially for smaller projects below 20 KWs of installed capacity. An alternative approach of using well-known ‘pump as turbine ’ technology can be contemplated and popularized. Pumps are readily available all over the world in every shape and size, mainly due to the ever-increasing demand for pumping application. Also the maintenance and operational issues in pumps are relatively much simpler. The most critical step in a ‘pump as turbine ’ technology is the selection of the most appropriate machine for a given application and the accurate prediction of the turbine mode performance characteristics. The dissertation has focused on detailed experimental investigations for both radial and mixed flow ‘pumps as turbines’, with an objective of developing ‘selection and performance ’ charts for the turbine mode operation that can b