Alternatives to R134a

For mobile air conditioning systems (MAC) with open drive compressors and hose connections in the refrigerant circuit, the risk of leakages is considerably higher than with stationary systems. An EU Directive (2006/40/EC) has been passed to reduce direct emissions in this application area. Within the scope of the Directive, and starting 2011, type approvals for new vehicles will only be granted if they use refrigerants with a global warming potential (GWP) of less than 150. Consequently, this excludes R134a (GWP = 1430) which has been used so far in these systems.

Meanwhile, alternative refrigerants and new technologies were developed and tested. This also involved a closer examination of the use of R152a.

For quite some time the automotive industry has agreed on so-called "Low GWP" refrigerants. The latter is dealt with as follows.

CO₂ technology, favored for this application for quite some time, has not been widely implemented for a variety of reasons ("Low GWP" HFO refrigerant R1234yf and CO₂ in car air conditioning systems).