Life cycle cost-benefit analysis of refrigerant replacement based on experience from a supermarket project

Abstract

The Kigali Amendment to the Montreal protocol calls for the phase-down of hydrofluorocarbons (HFC). With natural refrigerant gaining momentum worldwide, it is important to ascertain if the use of natural refrigerant reduce greenhouse gas emissions from refrigeration when the broader energy system in a cost-effective manner is considered. This study employs a generic process chain analysis framework to examine the life cycle costs and benefits of refrigerant replacement. The case study data are collected from a supermarket in China which has recently changed from a R22 system to a R134A-R744 system. There are three key findings from this study. First, the values of the life cycle greenhouse gas abatement costs can be significantly influenced by the costs and emissions due to electricity usage. Under a 15% discount rate, the reference values of the greenhouse gas abatement cost are found to be 207.28 and 1.40 $/t-CO2e with and without the costs and emissions due to electricity use respectively. Next, under the current state of technology development, cost reductions should be prioritised for natural refrigerant based system to become commercially attractive. Last and most important, current natural refrigerant based systems can only be suitable replacement of aging systems and/or systems approaching obsolescence.