A comparative performance analysis of selected refrigerants towards sustainable cooling

Abstract

The increasing demand for air conditioning to maintain room comfort, product quality, safety, and process efficiency especially in pharmaceutical industries worldwide and in developing countries like Uganda combined with the associated high electricity costs is contributing to global warming. Studies focusing on energy efficiency ratios in East Africa have provided limited information on seasonal energy efficiency of air conditioners using different refrigerants. Additionally, there is little information on a comprehensive assessment integrating energy consumption, environmental impact, and economic factors to support stakeholders in decision-making. This study investigated the comparative performance of air conditioner systems using R-290 and R-410A refrigerants by tracking the set room temperature, energy consumption, environmental impact, and operational life cycle costs over a 6-day experimental period. It was observed that the R-290 and R-410A air conditioner systems were both capable of closely tracking the set room temperature, with R-410A air conditioner system achieving closer adherence to the set room temperatures. Additionally, their energy consumption showed that R-290 air conditioner system consumed 4% less energy in descending set room temperature pattern (from 26℃ to 24℃ to 22℃), whereas R-410A system consumed 11% less energy in ascending set room temperature pattern (from 22°C to 24°C to 26°C). Generally, the R-410A air conditioner system consumed 2% less energy compared to the R-290 air conditioner system. In terms of environmental impact, the R-290 air conditioning system exhibited a significantly lower Total Equivalent Warming Impact (TEWI), with a difference of 142% compared to R-410A air conditioner system. However, R-410A air conditioner system demonstrated marginally lower total life cycle costs with a difference of 0.36% compared to the R-290 air conditioner system. Furthermore, the comparative analysis suggests that R-290 air conditioner system is more advantageous in terms of environmental sustainability and long-term viability, when considering commitment to the Montreal Protocol and the Kigali Amendment, which necessitate a reduction in the use of hydrofluorocarbons (R-410A) refrigerants. Six days of the experiment showed no significant difference in daily energy consumption between R-290 and R-410A air conditioner systems, presented no statistical difference in energy performance. Longer-term studies are recommended to assess performance across seasons and locations, while environmental impact, safety, and lifecycle costs remain important considerations