Exergoeconomic analysis and optimization of a cogeneration system using evolutionary programming

Exergoeconomic analysis helps designers to find ways to improve the performance of a system in a cost effective way. Most of the conventional exergoeconomic optimisation methods are iterative in nature and require the interpretation of the designer at each iteration. In this work, a cogeneration system that produces 50 MW of electricity and 15 kg/s of saturated steam at 2.5 bar is optimized using exergoeconomic principles and evolutionary programming. The analysis shows that the product cost, cost of electricity and steam, is 9.9% lower with respect to the base case. This is achieved, however, with 10% increase in capital investment. Moreover, it is important to note that the additional investment can be paid back in 3.23 years. (C) 2007 Elsevier Ltd. All rights reserved.