Advantages

CO2 GWP 1 (GWP = Global warming potential)

R507 GWP 3300

° CO2 is a naturally occurring gas/refrigerant, opposed to synthetic HFC’s (R507).

° Excellent heat capacity and transfer characteristics signify excellent refrigerant properties.

° High compressor discharge temperatures mean CO2 has excellent heat recovery potential.

° Smaller and more compact components are used in CO2 systems.

° CO2 is a long term viable refrigerant that is highly unlikely to be banned as a refrigerant.

° CO2 is a safe refrigerant, i.e. not flammable or toxic.

° CO2 is cheap & readily available and makes up 0.04% of the air that we breathe.

° CO2 is recovered as a by-product from other production processes.

° Lower energy consumption than traditional HFC systems indicate lower running costs.

Comparative System Reduction in consumption

HFC R507 5%

Pumped Glycol Systems 15%

° Leakage is not an environmental issue.

° CO2 is a green technology and has good PR & brand marketing potential.

Disadvantages

° Installation costs are likely to be up to 30% more until plant production levels increase.

° Presently there is a low level of Industry knowledge, therefore training will be required.

° High pressures at the case CO2 40 bar

R507 4 bar

° High pressures in the plant CO2 120 bar

R507 20 bar

° Using and managing CO2 as a refrigerant is a developing technology and as such system design and operating practices will continue to evolve. The early installations may not age well. However, without the early installations the technology cannot evolve in the first place.