Potential emission savings from refrigeration and air conditioning systems by using low GWP refrigerants

Purpose

Refrigeration and air conditioning systems have high, negative environmental impacts due to refrigerant charge leaks from the system and their corresponding high global warming potential. Thus, many efforts are in progress to obtain suitable low GWP alternative refrigerants and more environmentally friendly systems for the future. The system’s life cycle climate performance (LCCP) is a widespread metric proposed for the evaluation of the system’s environmental impact.

Methods

In this paper, the potential emission reductions in the commercial refrigeration and residential air conditioning systems, made possible by shifting towards more environmentally friendly refrigerants in the US, are presented. First, the current LCCP of the most common commercial refrigeration and residential air conditioning systems is calculated. Then, the LCCP of the baseline systems, when using the potential low GWP alternative refrigerants, is presented. This helps to determine the systems which have the highest potential for emission reductions.

Results and discussion

By shifting from the baseline refrigerants, R-404A and R-410A, to the suggested low GWP refrigerants, N-40 and L-41a, in the commercial refrigeration and residential HVAC systems, respectively, a combined drop of 30.43 % in the total emissions (i.e., total equivalent mass of emissions in kg CO_2eq) is obtained. This results from a 50.5 and 28.01 % drop in total emissions from supermarket refrigeration systems and residential air conditioning, respectively.

Conclusions

Shifting to lower GWP refrigerants in the refrigeration and air conditioning systems helps to reduce the total emissions and negative environmental impacts of these systems. Shifting to a secondary circuit commercial refrigeration system using N-40/L-40 and residential air conditioning and heat pump systems using L-41a helps in reducing the total emissions.