HEI’s Nick Shockley, associate and senior refrigeration design engineer, said, “In addition to the carbon footprint, we also had to consider energy efficiency, refrigeration capacity of the blend, system construction costs, refrigerant cost, and availability. R-407 (a blend of -32, -125, and -134a) provided the best overall solution for these parameters.”
Of the refrigerants considered for the application, only HFC-410A and HFC-407C had lower direct global warming potential than -407A. R-410A is common in air conditioning and several prototype refrigeration systems are in test using the refrigerant. But, according to a case study issued by National Refrigerants, “the lack of commercially available -410A refrigeration components has kept this option from being considered.”