Energy and Buildings 49 (2012) 62–68 Contents lists available at SciVerse ScienceDirect Energy and Buildings j our na l ho me p age: www.elsevier.com/locate/enbuild Experimental investigation of heat recovery system for building air conditioning in hot and humid areas Shahram Delfani a,∗ , Hadi Pasdarshahri b , Maryam Karami c a Department of Installations, Building and Housing Research Center (BHRC), PO Box 13145-1696, Tehran, Iran b Department of Mechanical Engineering, Tarbiat Modares University, PO Box 14115-143, Tehran, Iran c Department of Mechanical Engineering, University of Tehran, PO Box 14395-515, Tehran, Iran a r t i c l e i n f o Article history: Received 23 August 2011 Received in revised form 29 December 2011 Accepted 2 January 2012 Keywords: Heat recovery Thermal comfort Air conditioner Hot and humid area a b s t r a c t Nowadays, use of air-to-air heat recovery system combined to the cooling system is becoming necessary. Types of combination heat recovery and air conditioner must provide the comfort conditions and better indoor air quality for occupants in any climatic conditions. In this research, four types of air conditioning systems are evaluated experimentally. In each case, the amount of energy consumption by the aim of providing the thermal comfort, for various outdoor climatic conditions in hot and humid regions is eval- uated and compared. The contour plot of each experimental case is made, which shows the net energy consumption of systems based on the outdoor design condition. Finally, according to the experimental results, for selected hot and humid cities of Asia’s south and west countries (such as Abadan, Kuwait, Doha, Dehli, Bangkok), the rate of energy consumption of each cooling systems is calculated. It is shown that by using the heat recovery, energy consumption will reduce about 11–32% based on the system approach. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Environmentally sustainable design concepts include aspects related to the commercial and residential heating, ventilation and air-conditioning (HVAC) industry. Among several considerations, thermal comfort condition and indoor air quality (IAQ) are two important topics throughout the design and construction stages of a building’s life which should be attended. In this regard, proper ven- tilation helps improve IAQ. Ventilation can control indoor humidity and airborne contaminants, both of which either contribute to or act as health hazards. Therefore, in each HVAC system, an amount of fresh air is required to prepare thermal comfort and IAQ based on the application of the area. Many researchers have shown that thermal comfort can be affected on the occupants’ activity [1,2]. It should be noted the parameters such as indoor and outdoor design conditions and energy consumption have a great impact on providing thermal comfort. Nowadays, the urbanity and industrial growth have led people to spend 90% of their time in the buildings, which results in more energy demands for achieving thermal comfort [3,4]. Some of the south and west countries of Asia have high energy consumption. For example, Iran produces the energy equal to 1468.15 million barrels of raw oil annually. 39.8% of the energy ∗ Corresponding author. Tel.: +98 21 88255942; fax: +98 21 88255941. E-mail address: delfani@bhrc.ac.ir (S. Delfani). is used in the residential and commercial buildings [5]. It is nec- essary to reduce the heating and cooling energy consumption of the buildings. For example, in the south and north border of Iran, there are hot and humid climate regions, which conventionally use considerable amounts of electrical energy for operating cooling sys- tems. There are some serious problems in providing the electrical energy in the summer, it is crucial to reduce the cooling energy by introducing the new cooling systems. On this approach, one of the best choices is using heat recov- ery combined to an air conditioner which many researchers have noticed. It can be implied to the study of Lazzarin and Gasparella [7] who showed the energy recovery systems can be profitable even in low air mass flow rate in air conditioning systems. Furthermore, Fehrm et al. [8] researched about application of energy recovery systems in Europe. In the other research, Roulet et al. [9] studied energy consumption of the air handling units and recommended some advices for choosing types and sizes of the proper heat recov- ery systems. The research which was carried out by Besant and Simonson [10,11] and Dieckmann et al. [12] revealed that annual heating and cooling energy consumption can be reduced to one third by using the energy recovery system in an air tight building. For analyzing the climate regions’ effects on the energy con- sumption of the air conditioner which have energy recovery systems, many researches have been done. Ke and Yanming [13] studied the role of the recovery systems in reducing the energy consumption in eight cities of four different regions of China. Fur- thermore, Delfani et al. [14] surveyed the heat recovery system 0378-7788/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.enbuild.2012.01.002