Environment-Friendly Refrigerants for Sustainable Refrigeration and Air Conditioning: A Review

Abstract

Refrigeration and air conditioning systems play a vital role in our modern society, and refrigerants are integral components of these systems. Traditional refrigerants like chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have caused significant environmental concerns because of their role in ozone depletion and global warming. Consequently, interest has increased in developing and implementing environmentally benign refrigerants possessing minimal global warming potential (GWP) and no ozone depletion potential (ODP). This review explores the emerging field of environment-friendly refrigerants such as natural refrigerants (NH3, CO2, hydrocarbons), hydrofluoroolefins (HFOs), hydrofluorocarbons (HFCs) with ultra-low GWP, hydrofluoroethers (HFEs) and mixtures or blends of these refrigerants. The article also compares their thermophysical, thermodynamic, environmental and safety properties, and their suitability for different applications. The key recommendations encompass the promotion of natural refrigerants, including NH3, CO2, and hydrocarbons, exhibit minimal environmental effects. Additionally, the exploration of HFOs and HFCs with ultra-low GWP and their mixtures as potential substitutes is advised. Transitioning to environment-friendly refrigerants is essential for achieving sustainable refrigeration and air conditioning systems, mitigating climate change, and ensuring the long-term viability of cooling technologies while preserving the environment.