variavel0=<b>Celso Eduardo Tuna</b> - ctuna@bol.com.br Unisal - Lorena
<b>José Luz Silveira</b> - joseluz@feg.unesp.br Unesp - Campus de Guaratinguetá
<b>Abstract.</b> In this paper, two thermoeconomic analysis methods based on the Second Law of Thermodynamics, which are applied to analyze four cogeneration systems, are presented. The objective of the developed techniques is to minimize the operating costs of the cogeneration plant, namely Exergetic Production Cost (EPC). Fixed rates of electricity production and process steam in exergy base are assumed. The equations for calculating the capital costs of the components and products are formulated as a function of the decision variables. The first method is classified as an algebric one, and the second as a functional one. The conditions, which establish the minimum cost, are presented as finals conclusions.
<b>Keywords.</b> Thermoeconomic, Exergy, Cogeneration, Production Cost.