Role of Waste Cost in Theromeconomic Analysis and Impact of the Waste on Environment

Power plants or thermal systems wherein products such as electricity and steam are generated affect the natural environment, as well as human society, through the discharging of wastes. The wastes from such plants may include ashes, flue gases, and hot water streams. The waste cost is of primary importance in plant operation and industrial ecology. Therefore, an appropriate approach for including waste cost in a thermoeconomic analysis is essential. In this study, a method to take waste cost into account in thermoeconomics to determine the production cost of products via thermoeconomic analysis is proposed. The calculation of the waste cost flow rates leaving at the dissipative units and their allocation to system components are important to obtain the production cost of a plant. The cost flow rate of wastes, which may be regarded as a measure of impact of wastes on environment, are calculated for a coal fired power plant, CGAM cogeneration system and a combined cycle plant. How the cost flow imposed by CO 2 emission affects the cost flow rate of products is also discussed.