Testing of HFO-1234yf and R152a as mobile air conditioning refrigerant replacements

R134a has come under scrutiny for its contribution to greenhouse gases, which is 1,430 times greater than an equivalent mass of CO2. Industry has therefore begun searching for alternatives with a lower global warming potential (GWP). This paper reports on a project that focused on developing experience and gaining data with the most likely synthetic drop-in replacement candidates, R152a and HFO-1234yf. Both of these chemicals have some flammability issues but have no ozone depletion potential and have a significantly lower GWP. The testing regime involved both laboratory ¿bench testing¿, in a purpose-designed laboratory test bed, and also in-car testing. Both the bench and in-car testing were initially performed using the current industry standard mobile air conditioning refrigerant (R134a) to ascertain a base level of performance of the systems. Both of the replacement refrigerants had COPs and cooling capacities similar to R134a, with R152 having slightly higher values and HFO-1234yf slightly lower.