Abstract
Any analysis and optimization of complex technical systems based on the methods of classical thermodynamics are associated with certain difficulties. They are explained by the fact that thermodynamic analysis operates in terms of «energy costs» and «energy losses», while for a full assessment, it is necessary to take into account all types of costs. Consequently, any analysis and optimization must take into account economic cost calculations and ultimately lead to savings in natural resources and human labour. In many cases, the term «energy «is replaced by the term «exergy». The main task of the analysis in terms of exergy is to study the degree of perfection of processes. However, only the exergy method is not able to give results that are fundamentally different from the classical thermodynamic. The method of solving the optimization problem is based on the use of exergoeconomical method, which allows to establish the interaction of thermodynamic and cost parameters and to take the cost of the unit of exergy in the energy conversion processes as the main indicator. The formulation of the problem of optimization of complex energy systems «combined cycle gas turbine unit - lithium bromide absorption chiller» as a single energy unit is described.