Isobutane (R600a) has been extensively utilized in residential refrigerators in various countries throughout the globe since the 1990s, when the NGO Greenpeace debuted their GreenFreeze idea, with a maximum charge of 150g (5.3oz).
The Environmental Protection Agency (EPA) did not raise the change limit for R600a in home refrigerators from 57g (2oz) to 150g until September 2018; hence progress has been slower in the world. However, last year, shops in the different states started stocking various full-size R600a refrigerators/freezers.
Nigerian researchers have established the prudence of using R600a instead of a high-GWP HFC refrigerant in a study published in the Journal of Physics: Conference Series. Solomon Banjo, an engineer in the Mechanical Engineering Department at Covenant University in Ota, Nigeria, led the study.
The research, “Experimental Examination of the performance characteristics of an eco-friendly HC600a as a retrofitting refrigerant in a thermal system,” looked at the performance of a residential refrigerator that used 46g (1.6oz) of R600a instead of 70g (2.5oz) of R134a.
Notably, the researchers tested both refrigerants, first R134a and subsequently, with minor retrofitting, R600a, at an ambient temperature of 28°C (82°F) using the same system. “Some system components, such as the compressor, mineral oil, capillary tube, and dryer, were modified to fit the new design,” according to the report.
According to the study’s findings, R600a raised the system’s coefficient of performance (COP) by 32.2 percent while lowering energy consumption by 4.5 percent. Furthermore, the R600a system reached an evaporation temperature of -21°C (-5.8°F) in 60 minutes (pull-down time), compared to 2 hours and 15 minutes with R134a.
In conclusion, The COP of the R600a system ranged from 7-8, whereas the COP of the R134a system ranged from 5 to 6.5 during a five-hour test. The power of the R600a system was 85W for the final 150 minutes of the trial, whereas the power of the R134a system was 89W.
According to the research, the heat rejection of the condenser was also 12.8 percent higher with R600a than with R134a.
Westron can examine your facility independently and recommend an appropriate refrigerant. As industrial refrigeration engineers, their concepts, products, and installations are compatible with the most popular refrigerants.