Life Cycle Cost Analysis for Variable Refrigerant Flow (VRF) and Constant Refrigerant Flow (CRF) Air Conditioning Systems in Arid Climate: Case Study in Qatar

Abstract

All over the world, there is a call to encourage sustainable energy thinking and implementation. In the heating, ventilation and air conditioning field, the rise of the variable refrigerant flow systems has made a big progress. This study presents a life-cycle cost analysis to evaluate the economic feasibility of constant refrigerant flow (CRF) in particular the conventional ducted unit air conditioning system and the variable refrigerant flow (VRF) system by using detailed cooling load profiles, initial, operating, and maintenance costs. Two operating hour scenarios are utilized and the present-worth value technique for life-cycle cost analysis is applied to an existing office building located in Qatar which can be conditioned by CRF and VRF systems. The results indicate that although the initial cost of the VRF system is higher than that of the CRF system, the present-worth cost of the VRF system is lower than that of the CRF system at the end of the lifetime due to lower operating costs. The implementation of these results on a national scale will promote the use of sustainable energy technologies such as the VRF system.