Reduce Greenhouse Gas Emissions With Natural Refrigerants

A natural refrigerant is a substance that occurs naturally or is already present in the Earth’s atmosphere or natural environment. The most common natural refrigerants in use today are refrigerant-grade versions of carbon dioxide (CO₂ or refrigerant name R-744), the hydrocarbon propane (R-290) and ammonia (R-717.)

Natural refrigerants have unique properties that require adherence to proper safety protocols in system design, manufacturing and handling. Because CO₂ is a high-pressure refrigerant, system piping, valves and equipment must be rated for these pressures and allow for built-in pressure relief. R-290 is flammable and requires equipment to be designed to minimize the potential for ignition potential. Because of its potential toxicity, R-717 leaks must be quickly detected so that building occupants can be evacuated. Modern refrigeration technologies have evolved to ensure equipment safety and enable the use of these refrigerants in designated applications.

Natural refrigerants have evolved to fill very specific niches in commercial and industrial refrigeration applications. CO₂ is more common in centralized refrigeration systems, such as CO₂ transcritical booster. R-290 is mostly limited to lower charge limits and is typically found in stand-alone, self-contained display cases. R-717 delivers excellent performance in large cold storage and industrial refrigeration applications.  

Natural refrigerants have very low-global warming (GWPs) and ozone depletion potentials:

• R-744 has a GWP of 1 and an ODP of 0.
• R-290 has a GWP of 3 and an ODP of 0.
• R-717 has 0 GWP and ODP.