Abstract:
Economic dispatch has been used in many power plants to optimize the plants operation. As one of method in economic dispatch, Lagrange multiplier method was utilized for calculating the economic operation in power system of PT. PLN-Manokwari branch which is the electrical company working in area of Manokwari. This power system includes nine units and the other rental units of diesel power plant. Based on some schemes which had been designed and calculated with Lagrange multiplier method, the most economic unit refers to diesel power plant unit P1 with prime mover DEUTZ BV8 M 628 while diesel power plant unit P6 with prime mover MITSUBISHI S12 R-PTA is indicated as the least economic unit at the system. The system shows existence of good efficiency when working for schemes 3500 to 6000 kW and for schemes above 6000 kW, the operating expenses are increasing significantly in the consequence of operating of the low efficient units. Result of calculation using average daily generating power shows that this power system will be very optimal using economic dispatch.
