Cold production systems are responsible for a large share of all energy consumption and a major source of greenhouse gas (GHG) emissions. Existing supermarket refrigeration systems, for example, use large quantities of synthetic refrigerants (1,000 to 2,000 kg of HCFCs or HFCs per store). Pressurized refrigerant travels from the mechanical room to the different display counters through kilometres of lines containing hundreds of joints. Such systems are responsible for major leaks of refrigerant (20% to 30% of the charge per year¹) that act as powerful greenhouse gases.

Based on multiple tests with thermodynamic systems and those employing a secondary fluid, HFCs, ammonia, geothermics and CO_2, we work with our clients to develop a customized process that combines the full benefits of top-end refrigeration systems. Our experience in these multiple applications is unexcelled anywhere on the market.

Operators may select from among a range of options. They may, for example, decide to combine the use of CO₂ with another environmentally friendly refrigerant or to employ CO₂ as the sole refrigerant, depending on their requirements.

In a cascade system, we maintain CO₂ at pressures acceptable to most known manufacturers of commonly available parts, to ensure easy access to parts and equipment. We then combine the excellent thermodynamic properties of CO₂ with the outstanding benefits of ammonia, for example, to create new systems readily exceeding the performance of those presently on the market.

In the case of transcritical CO₂ systems, we have built an excellent network of suppliers to support such equipment, thereby ensuring the security of your cold chain.

The use of CO₂ for refrigeration is a technology that first emerged in the middle of the 19^th century and came into its golden age between 1920 to 1930, before it was gradually discarded in favour of synthetic refrigerants. CO₂ began to reappear in the 1990s and has become increasingly popular ever since.

CO₂ offers many advantages over synthetic refrigerants:

• It is a natural, safe (non-toxic) and inexpensive refrigerant. Its climatic impact is 1/1,500 to 1/4,000 that of synthetic refrigerants.
• It possesses better heat transfer qualities than synthetic refrigerants and can boost system efficiency.
• It must operate at high pressures, which enhance system efficiency and reduce component and tubing size, to permit the design of more compact systems.

Ammonia offers the following benefits:

• Ammonia is a safe natural refrigerant when used according to the rules of the trade.
• It has no impact on the ozone layer or on global warming.
• Its unequalled thermodynamic properties yield exceptional energy savings.

Not only do such synthetic refrigerants as HCFCs (R22) and HFCs (R404, R507) harm the environment, they must be used in larger systems. Such systems demand additional and bigger compressions. The cost of these refrigerants is much greater than CO₂.

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¹ Revised draft analysis U.S. Commercial supermarket refrigeration systems

CO₂ (R744) and NH3 (R717) Pressure Temperature Chart

CO₂ (R744) Chart and NH3 (R717) Chart Pocket-size