Energy and exergy analysis of heating and cooling systems in the hotel example

Nowadays, one of the biggest problems in the world is energy. Therefore, the measures to be taken in terms of energy consumption are very important for both the national economy and the world economy. Most of the energy consumption in our country is caused by buildings and HVAC systems constitute the majority of this consumption. In order to save energy on the systems, energy and exergy analyzes should be performed and as a result, which HVAC system is more efficient should be decided. In this study, initially, energy and exergy analysis is discussed in general terms. Afterwards, energy and exergy analyzes were performed in the heating and cooling systems of a restored hotel in Bolu. Thus, it was emphasized how much of the energy used in the system can be converted into useful work with energy transfers. According to energy analyses for heating systems; it is indicated that heat exchanger has got lowest efficiency, but boiler has got high efficiency. According to exergy analyses for heating systems; fan coil has got the highest efficiency but boiler has got the lowest efficiency. Energy analyses which are performed for cooling systems has got highest efficiency in chiller, but the lowest efficiency on fan coil and air heating unit line. For exergy analyses, it is determined that lowest efficiency is exercised in chiller and the highest efficiency is exercised in air heating unit (AHU) and fan coil line. According to the analyzes, it was revealed that exergy analyses are more realistic than the energy analyses. It was seen that energy efficiency can be achieved making improvements in the boiler and chiller due to exergy analysis.