Chapter 7 - Thermoeconomics

Abstract

This chapter provides economical considerations for the optimization of the subsystems. Thermodynamics principles have implications for energy management and economics. For optimizing the design and operating conditions of thermal systems, thermoeconomics usually relates exergy and economics. The complexity of the optimization problem depends on the complexity of the constraints, which may be in algebraic, difference, differential, and integral forms. The cost of thermal energy source plays an important role in the optimization, for example, changing the fuel cost from one year toanother and from one place to another affects the overall design and hence the economical considerations. Thermodynamics can deal with the economic balance through the availability analysis and exergy optimization. Minimization of entropy generation plays only a secondary role in thermoeconomics, mainly because the economic performance is formulated in economic values of money and prices. Therefore, the thermodynamic optimization problem may not be broken down to the problem of minimization of irreversibility. The industrial systems consist of various resource consumption processes and the supporting processes associated with the supply and removal of resources. Contemporary theory of optimization is used for analyzing the systems. The first approach is to optimize the system by adjusting the design and operating parameters through the governing equations that describe the internal changes, and by imposing a control through the system boundaries. The second approach aims to predict the system behavior under the specified external conditions by deriving its governing equations from certain variational or extremum principles.