Abstract:
Large Pelton turbines used in major hydro applications are of high efficiency, in the range of 92% or more. However, Peltons used in mini-hydro applications in Sri Lanka were often found to be of lower efficiency, and of micro range much lower. The main factors affecting efficiency are identified as per available literature and analytically discussed.. Effect of nozzle efficiency, bucket friction, speed ratio and bucket geometry are further analyzed as per a novel theoretical derivation. These are compared with available practical data and experience. The results are discussed with a view to improve the efficiency of mini/micro range of Pelton turbines and recommendations made accordingly.