- Relief to a global concern
Global warming and ozone depletion has been a global concern since the 1970’s. Traditional refrigerants were at the height of these concerns and began being phased out in 1987, giving rise to innovative zero-Ozone Depletion Potential (zero-ODP) and low Global Warming Potential (GWP) refrigerants.
- CO2 mass and Greenhouse gas
The GWP of a refrigerant is measured because of its direct contribution to climate change. Here’s how it’s calculated:
- A refrigerant releases a certain gas (a greenhouse gas) into the atmosphere
- This expelled gas (with a mass of 1) traps heat
- Carbon Dioxide (with a mass of 1) also traps heat
- The amount of trapped heat within the greenhouse gas and the CO2 is then compared
- This is usually calculated over a period of 100 years
So the lower the GWP value compared to the CO2 value, the better!
- ODP versus GWP
Many refrigerants today use chemicals that have zero Ozone Depletion Potential (zero-ODP). This, however, does not mean they have low GWP. If a refrigerant has ODP, it is then assigned a value. This value indicates how strongly the refrigerant depletes the ozone, the strength of the chemical causing ozone degradation. All refrigerants have GWP, but not all have ODP.
- Which chemicals should your refrigerant use?
Current refrigerants use Hydrofluorocarbons to mitigate ozone depletion. HFC’s (containing Hydrogen, Fluorine and Carbon chemicals), have zero-ODP. Despite this, they still have GWP – meaning that refrigerants should be used responsibly and continually monitored.
The next generation of refrigerants contain HFO’s (Hydrofluoro-olefins) or an HFC/HFO blend. HFO refrigerants have a lower GWP, are cost effective, energy efficient, non-toxic, only mildly flammable (HFC/HFO blends are non-flammable) and, as with HFC’s, they have zero-ODP.
- Bitzer is leading the way
In 2015, Bitzer became the first compressor manufacturer to approve a full range of low GWP refrigerants. HFO/HFC blends R448A and R449A were developed as substitutes for the phased out, high GWP commercial refrigeration gases – R404A and R507A. The substitutes have about a third of the global warming potential of R404A/R507A.