Energy saving and applications in heating and cooling systems in buildings

In a continuous development in the areas of technology and an increasing World's population bring an intensive energy consumption. The use of energy per human in developed countries are higher than developing countries. Moreover, The greatness of the energy used per person in a country is related to development state of that country. When It is considered that fossil resources (natural gas, coke, oil etc.) on the earth are limited, It is understood that energy efficiency is so important. By proper energy effiency studies, both a large amount of economic gain can be obtained across the country and harmful gases that cause to global warming and air pollution can be notably dimished. The amount of energy used for heating and cooling purposes in buildings and industrial areas is highly much. So a proper energy efficiency analysis is needed. In this study, The analysis of energy efficiency carried out at centrifugal pump-valve combination and applications for this purpose are analyzed and investigated. For analysis of energy efficiency in heating and cooling systems, the most important devices are pumps and valves. The pump provides needed flowrate and DP for the system. Valves at pipe line contract flowrate and DP. So pumps and valves are key instruments for energy efficiency. In this study, energy efficiency, Turkey-World energy situation and standarts and laws related to energy efficiency are primarily mentioned. Additionally, the researches about efficiency of balancing valves, motorized valves, frequency converters and electric motors which are placed in the same system with pumps carried out. In addition, In order to operate centrifugal pumps in an efficient way, some measures are investigated. Also in this thesis, the pump used in a heating- cooling system of a building is respectively operated with the applications of constant flow, constant DP and proportional control. Frequency converter is used to operate the pump under constant DP and proportional control. The result of the experiment, The numerical values of electric energy consumed by 3 different control groups(constant flowrate, constant DP and proportional control) were found and these values were examined the aspect of energy efficiency. Therefore, the amount of percentages of energy savings obtained the use of frequency converter were calculated. According to the calculations made, the pump with frequency converter and proportional control consumes 53.8% less energy than the constant flow pump and constant DP pump consumes 20.86% less electrical energy than the constant flow pump. Thus, it has been revealed that pumps with frequency converters and proportional controls should be used in pumps operating under partial loads.