Solution for question: Electric power is to be generated by installing a hydraulic turbine-generator at a site 70m below the free surface of a large water reservoir that can supply water at a rate of 1500kg/s steadily. If the mechanical power output of the turbine is 800kW and the electric power generation is 750kW, determine the turbine efficiency and the combined turbine-generator efficiency of this plant. Neglect losses in the pipes.