Climate-conscious shoppers may buy local food and try to cut packaging waste, but those efforts could be negated by potent greenhouse gases leaking from supermarket fridges.

Refrigerants called hydrofluorocarbons or HFCs are widely used to keep food cold or frozen at grocery stores and during transport. (They're also used for other refrigeration applications, like ice rinks and air conditioners).

They were originally brought in to replace ozone-depleting refrigerants called chlorofluorocarbons (CFCs), which were banned in a landmark 1987 agreement called the Montreal Protocol, in order to save the Earth's protective ozone layer.

But HFCs are themselves powerful greenhouse gases.

Typically, each tonne of HFCs can trap as much heat in the atmosphere as 1,400 to 4,000 tonnes of carbon dioxide over 100 years, depending on the type of HFC.

What can be used for refrigeration in place of HFCs?

The main alternatives are called "natural" refrigerants because they are all chemicals found in nature. They include:

CO2.
Ammonia.
Propane.
While CO2 is a greenhouse gas, its global warming potential is so much lower than that of HFCs. And propane, while it's a fossil fuel, is not burned when used in refrigeration. In fact, all three of these chemicals are considered refrigerants with ultra-low global warming potential.


https://www.cbc.ca/news/science/hfc-climate-supermarkets-1.6726627
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