Parametric based thermo-environmental and exergoeconomic analyses of a combined cycle power plant with regression analysis and optimization

A combined cycle power plant is analyzed through thermo-environmental, exergoeconomic and statistical methods. The plant is first modeled and parametrically studied to deliberate the effects of various operating parameters on the thermo-environmental quantities, like net power output, energy efficiency, exergy efficiency and CO2 emissions. These quantities are then correlated with operating parameters through multiple polynomial regression analysis. Moreover, exergoeconomic analysis is performed to look into the impact of operating parameters on fuel cost, capital cost and exergy destruction cost. The optimal operating parameters are then determined using the Nelder-Mead simplex method by defining two objective functions, namely exergy efficiency (maximized) and total cost (minimized). According to the parametric analysis, the operating parameters impart significant effects on the performance and cost rates. The regression models are appearing to be a good estimator of the response variables since appended with satisfactory R-2 values. The optimization results exhibit that the exergy efficiency is increased and cost rates are decreased by selecting the best trade-off values at different power output conditions. (C) 2014 Elsevier Ltd. All rights reserved.