The paper present the approach of thermo-economic analysis of centralized cold generation in trigeneration system integrated with steam-powered absorption chillers. The analysis was conducted for real back-pressure combined heat and power (CHP) unit BC-50 and single-effect absorption refrigerators using water and lithium bromide as the working fluids. It has been assumed that the heating medium supplied to the chiller generator is technological steam from the existing steam bleeding. Mathematical simulation models of cogeneration and trigeneration systems have been developed with the commercial program for power plant simulation EBSILON®Professional. System effects of heat and electricity cogeneration and cogeneration with additional cold production have been calculated. The effect of trigeneration has been assessed quantitatively by the coefficient of the increasing the cogeneration effects, which has been calculated as a fraction of ratio of chemical energy savings of fuels to the demand for heat by the consumers in the cases of trigeneration and cogeneration. The paper includes also analysis of economic effectiveness of a trigeneration system with absorption chillers for cold agent production. The results of economic calculations show that an acceptable payback period of approximately thirteen years for a CHP and absorption system may be achieved, which is equal to the half of assumed operating time of the system. The carry out sensitivity analysis shows that the most important impact on profitability is the selling price of cold and the purchase of fuel – hard coal.
