Dr. Raj Kumar Dreepaul
Department of Electromechanical Engineering, Faculty of Sustainable Development and Engineering, Universite des Mascareignes, Mauritius.

Speech title: A study of Alternative Refrigerants for the Refrigeration and Air conditioning sector in Mauritius

Abstract: The most frequently used refrigerants in the refrigeration and air conditioning (RAC) sector in Mauritius are currently hydrochlorofluorocarbons (HCFC) and hydrofluorocarbons (HFC). However because of their strong influence on global warming and the impact of HCFCs on the ozone layer, refrigerants such as ammonia (NH₃), carbon dioxide (CO₂) and Hydrocarbons (HC), having minimal impact on the environment, are being considered. So far HCs have only been safely used in domestic refrigeration. Ammonia has been used mainly for industrial refrigeration whereas CO₂ is still under study. In this paper a comparative study of the various feasible alternatives are presented in the light a survey that was undertaken with major stake holders in the field. The retrofitting possibility of existing equipment was assessed and safety issues associated with each refrigerant analysed. The major setback of hydrocarbons as a widely accepted refrigerant is its flammability which was considered as a major safety hazard by the majority of respondents in the survey and the main advantages are the improved equipment Coefficient of performance (COP) and better TEWI factor. This resulted in a 12 % drop in energy consumption. Despite the excellent thermodynamic properties of ammonia, its use has mainly been confined to industrial refrigeration due to its toxicity. In Mauritius the performance of ammonia in air conditioning is being evaluated on a pilot basis. The major setback of carbon dioxide as a refrigerant is the high operating pressure which is considered a safety hazard. The high initial investment cost and the lack of qualified maintenance technician is also an issue. The use of CO2 is mainly being considered in the commercial refrigeration sector.