As we known that: Capacity Factor or Plant Factor: It may be defined as the ratio of average output of the plant for a given period of time to the plant capacity, i.e., Capacity factor = Average Load (over a given period of time)/ plant capacity As given, that: Plant capacity = 10,000 kW Average Load = 40,000 kWh /100 hours So, Capacity factor of hydro power = (40,000/100)/10,000 = 0.4 or 40%