Abstract
Power generation in Saudi Arabia is mostly from thermal power plants. This paper involves the minimization of the total cost of power generation from thermal plants in the Western Operating Area of Saudi Electricity Company, incorporating the environmental constraints and the transmission line losses. Economic Dispatch is one of the most important function that is performed in a power system control center so as to minimize the oil consumption in thermal power plants and thus decrease the power generation cost. As the power generation process in thermal power plants causes the emission of significant amount of harmful gases such as carbon dioxide (CO2), and oxide of nitrogen (NOx), it is important to minimize the emission of these gases by appropriate allocation of the total power demand among the various power plants in the system on a continuous basis. Hence this paper focusses on the minimization of the fuel cost of the thermal power plants subjected to these emission constraints. The gradient descent technique based on Lagrange multiplier method is utilized in this environmental economic dispatch of the thermal power plants. Investigations are carried out with the daily hourly load curve corresponding to three days, each one covering three different seasons: summer, winter and Hajj. The investigations reveal that a considerable reduction in the emission of gases can be achieved with the implementation of the environmental economic dispatch function in the area load dispatch center