The refrigerant commonly used in mobile air conditioning (MAC) systems is tetrafluoroethane, R134a for short. R134a has a high global warming potential (GWP), 1,300 times higher - according to more recent calculations by the Intergovernmental Panel on Climate Change (IPCC), even 1,430 times higher – than that of CO2. A car equipped with air conditioning produces additional emissions  corresponding to 7 grams of CO2 per driven kilometre by the continuous release of R134a from the system. As a result, MAC systems have been veritable climate offenders up to the present.