A Power Plant Simulation Using Absorption Chillers For District Cooling M. Zeki YILMAZOĞLU Gazi University Faculty of Engineering Department of Mechanical Engineering, Ankara Email: zekiyilmazoglu@gazi.edu.tr SUMMARY Considering the serious results of Green House Gases that have become more apparent in the World nature lately, energy efficiency has gained great importance for the researchers, energy and fuel companies and countries that give importance to the clean, efficient and low-cost energy projects. Beyond the new studies focusing on new or renewable energy resources, the ones investigating the new technologies on existing energy-producing systems are of considerable significance. In the search of more efficient heating and cooling systems, district cooling and heating (DCH) systems become a widely-studied area. With this purpose, this study aims to simulate a condensing type of cogeneration plant for district cooling with the use of THERMOFLEX software, where absorption chillers are used to supply the cooling demand. Component and electricity-fuel costs and number of houses that can benefit from this system are calculated for all cases of single and double effect systems of absorption and individual chillers. Additionally, the effects of bled steam pressure on system performance and the size of heat exchanger are investigated. Amounts of stack exhaust gases are obtained and discussed briefly according to the Legislations of environment. An approximate pay-back time is also obtained for the plant with the specified unit electricity and natural gas prices in Turkey. All results are used for comparison with the conventional chillers with the energy economy point of view. INTRODUCTION According to the researchers, green house gases (GHG) emission to the atmospehere has increased by 50% in the last 30 years [1]. One reason for this problem is the general preferance of high exergy potential resources such as natural gas or electricity. The excessive electricity consumption during the warm seasons for the necessity of of cooling the living and working environments is an example. For this purpose, due to their suitable investment costs, mechanical compression chillers are used which make up the 10% share of the total annual electricity consumption. As a result of greater electricity demand, green house gases are emitted more by the thermal power plants. Observing the serious results of CO 2 emissions on nature all over the world, it is clear that energy efficiency is the key factor for the solution or at least the reduction of high emission statistics. In parallel, EU explains its aim of reducing the GHG emission by 20% until the year 2020. Some of the precautions to be taken or at least suggested can be summarized as follows. Using absorption chillers to utilize waste heat or renewables, adapting low temperature heating and high temperature cooling systems (radiant heating & cooling systems) to residential or commercial buildings, connecting the heating and cooling networks, prevailing