Environmental impact
The environmental impact plays an important role when choosing a refrigerant. Today, the ozone depletion potential shall be 0, the global warming potential shall be very low and other impacts on environment shall also be very low. Regarding many fluorinated gases, the atmospheric break down products are considered as critical. The production effort should also be as low as possible.
As the consumption of electrical energy today leads to emissions too, the so called indirect emissions, the energy efficiency is considered relevant for environment (Details: Emissions).