Environmental Influence on the Thermoeconomic Optimization of a Combined Plant With NOx Abatement

Abstract

Methods to analyze, improve, and optimize thermal energy systems have to take into account not only energy (exergy) consumption and economic resources, but also pollution and degradation of the environment. The term “environomics” implies a method that takes thermodynamic, economic, and environmental aspects systematically into consideration for the analysis and optimization of energy systems. For optimization of energy systems, the environmental aspects are quantified and introduced into the objective function. In this particular work, the environomic approach is followed for the analysis and optimal design of a combined-cycle plant. In addition to the basic configuration, two alternatives for NOx abatement are studied: Selective Catalytic Reduction (SCR) and steam injection. The optimization problem is solved for each configuration, and the results are compared with each other. The effect of the unit pollution penalties and of the limits imposed by regulations is studied. Some general conclusions are drawn.