INTERNATIONAL JOURNAL OF ENERGY RESEARCH Exergy, economic and environment (3E) analysis of absorption chiller inlet air cooler used in gas turbine power plants M. A. Ehyaei 1 , S. Hakimzadeh 2 , N. Enadi 3 and P. Ahmadi 4,Ã,y 1 Islamic Azad University, Pardis Branch, Pardis New City, Tehran, Iran 2 Islamic Azad University, Dezful Branch, Dezful City, Khuzestan, Iran 3 Energy Engineering Department, Power and Water University of Technology (PWUT), Tehran, Iran 4 Clean Energy Research Lab (CERL), Department of Mechanical Engineering, Faculty of Engineering and Applied Science, University of Ontario, Institute of Technology (UOIT), 23–19 Niagara DR, Oshawa, Ont., Canada L1G 8G2 SUMMARY Gas turbine (GT) output power is affected by temperature, gas turbine inlet air-cooling systems are used to solve this. In the present work, the effect of using absorption chiller in GT power plants for two regions in Iran, namely Tabas with hot–dry and Bushehr with hot–humid climate conditions is conducted. Therefore, output power, first and second law efficiencies, environmental and electrical costs for GT power plant with inlet air cooler are calculated for two mentioned regions, respectively. Results show that using this system in hot months of a year is economical. In addition, using absorption chiller leads to increasing the output power 11.5 and 10.3%, for Tabas and Bushehr cities, respectively. Moreover, by using this method the second law efficiency is increased to 22.9 and 29.4% for Tabas and Bushehr cities, respectively. In addition, the cost of electricity production for Tabas and Bushehr cities decreases to about 5.04 and 2.97%, respectively. Copyright r 2011 John Wiley & Sons, Ltd. KEY WORDS exergy; gas turbine; absorption chiller; cost of electricity production Correspondence *P. Ahmadi, Clean Energy Research Lab (CERL), Department of Mechanical Engineering, Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (UOIT), 23-19 Niagara DR, Oshawa, Ont., Canada L1G 8G2. y E-mail: Pouryaahmadi81@gmail.com, Pouria.ahmadi@uoit.ca Received 21 May 2010; Revised 6 December 2010; Accepted 7 December 2010 1. INTRODUCTION Gas turbine (GT) power plants are significantly impacted by the ambient air temperature. Hence, output power of these cycles decreases with increase in the ambient temperature. The GT is known to feature low capital cost to power ratio, high flexibility, high reliability without complexity, short delivery time, early commissioning and commercial operation. According to a survey [1,2], there are more than 170 GT units used in Iran. The total capacity of these units is around 9500 MW. However, the power output of the units is about 80% of their rated capacity in the summer. It means that around 1900 MW are lost during the hot season. GT output power strongly depends on the inlet air mass flow rate. Therefore, the available output power considerably reduces when the air density decreases at high ambient temperatures. Thus, GT output power is a strong function of the ambient air temperature with power output dropping by 0.5–0.9% for every 11C rise in the ambient temperature. On several heavy duty frame GTs, power output drops of around 20% can be experienced when the ambient temperature reaches 351C, coupled with a heat rate increase of about 5%. This is due to reduced inlet air density and mass flow rate [1]. Therefore, the solution of this problem is very important because the peak demand season also happens in hot days of summer. One approach to overcome this problem during periods of high ambient temperature (high demand period) is to cool the inlet air. There are several inlet air-cooling technologies available such as inlet air fogging system, direct refrigeration, electrically driven chillers or absorption chillers. One of these options is absorption cooling system. While the mechanical refrigeration can reduce the GT inlet temperature below the wet bulb temperature, the absorption system is relatively simple and has a lower operation and maintenance cost than the Copyright r 2011 John Wiley & Sons, Ltd. Int. J. Energy Res. 2012; 36: – Published online February 2011 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/er.1814 486 498 7 486