Thermoeconomic analysis of central and individual heating systems

Gradual decrease in the fossil based energy sources and the increase in the life standart of societies cause a gradual increase in energy costs. On the other and, use of fossil based fuel as the basic energy source by the communities introduces significant environmental problems. These problems have brought up the issues of efficiency, cost effectiveness and use of pure energy sources as far as energy consumption is concerned. Recently, efficiency analysis of thermal systems has been a popular concern for scientists. Today in the analysis of thermal systems, the second law of thermodynamics is used as well as the first law of thermodynamics. The analysis method bases on both of these rules is called exergy analysis and has a significant part in efficiency and cost effectiveness analysis. Seen from this aspect, in our country where 1/3 of energ consumption is allocated to heating at buildings, energy and exergy analysis is naturally a key point. In this study, thermodynamical examination of systems of which heat load was calculated both individually and centrally has been deliverd. A cost analysis was conducted for a central and individual heating system of a 5 storeyed symmetrical building in stanbul and it was found that thermodynamical factor of individual system was higher than that of central system by calculating the unused amount of exergy. This means that the cost of first investment in individual system is higher whereas by reducing the exergy destruction, in other words increasing the component efficiency, a cost saving method can be achieved in the entire system. Similar comparisons have been offered in the whole project since they are considered to guide, especially in terms of energy savings, the process of selecting a heating system that will be used in buildings. Keywords : Central heating system, individual heating system, exergy, thermoeconomy, energy savings.