Cold Link Africa June 2025 | Page 23

© Cold Link Africa

INCORPORATING COLD CHAIN

2. Invest in flexible equipment Install systems capable of handling a wide range of synthetic refrigerants and managing transitions in line with Kigali phasedown milestones.

3. Adopt natural refrigerants Transition directly to natural refrigerants like hydrocarbons or R744, bypassing interim steps such as using HFCs.

FINAL THOUGHTS

The journey towards a low-GWP future is complex but essential for environmental and regulatory compliance. Industry stakeholders must weigh their options carefully, considering both immediate costs, long-term benefits and system implications *. By choosing the right pathway, South Africa’ s HVAC & R sector can achieve a seamless transition while contributing to global efforts to mitigate climate change.

By the conclusion of 2025, the R22 refrigerant market will undergo significant changes. Ultimately, any decision made during the transition will carry financial implications.

During this phasedown, as in the previous transition away from CFCs, A-Gas offers a range of alternative refrigerants.

* Please see the table below as to what considerations you need to take when deciding on the suitable alternative for your system.

Andy Pearson, Star Refrigeration.

NATURAL REFRIGERANTS GAIN TRACTION

Natural refrigerants have gained traction due to their low environmental impact and energy efficiency. Key developments include:

• Hydrocarbons( R-290, R-600a): Propane( R-290) and isobutane( R-600a) have become widely adopted in domestic and commercial refrigeration. R-600a dominates the domestic refrigerator market due to its safety and efficiency.

• Ammonia( R-717): A proven refrigerant in industrial applications, ammonia has seen a resurgence thanks to modern systems that minimise leakage risks.

• Carbon Dioxide( R-744): CO₂ has proven effective in commercial freezers and heat pumps, though its efficiency and cost remain challenges in some applications.

While natural refrigerants offer clear environmental benefits, their adoption involves trade-offs:

• Safety: Hydrocarbons are flammable, requiring stringent safety measures. Ammonia, though efficient, is toxic and requires careful handling.

• Efficiency: CO₂ systems can be less efficient than HFCs in high-ambient conditions, though advancements in transcritical CO₂ technology are improving performance.

• Cost: Initial investments in natural refrigerant systems can be higher, though long-term energy savings often offset these costs.

The future of refrigeration is poised for a significant shift toward natural refrigerants, as environmental regulations grow stricter and the demand for sustainable cooling solutions rises. This transition will likely unfold across several key sectors.

In industrial applications, ammonia and CO₂ are expected to remain the dominant choices for large-scale refrigeration, with ongoing innovations aimed at reducing charge sizes and enhancing safety measures. Meanwhile, the commercial refrigeration sector— particularly supermarkets— is increasingly adopting CO₂-based systems, including cascade and transcritical configurations, while propane gains traction in display cases due to its efficiency and lower environmental impact.

Heat pumps are another area of advancement, where CO₂ based systems show strong potential for high-temperature applications. However, ammonia and hydrocarbons continue to hold their own as viable alternatives, ensuring a competitive landscape as the industry evolves toward greener solutions.

Natural refrigerants represent a viable path toward sustainable cooling. While challenges remain— particularly in safety, efficiency, and cost— ongoing advancements and regulatory support will accelerate their adoption. As the industry moves away from fluorinated gases, natural refrigerants will play a pivotal role in reducing the environmental impact of refrigeration systems.

REFERENCE:

1. Dr Andy Pearson / Droetsi Memorial Lecture in Johannesburg

THE POTENTIAL OF CO₂ IN HVAC & R: A SUSTAINABLE SHIFT FOR THE FUTURE

With a remarkably low Global Warming Potential( GWP) of just one, CO₂ has emerged as a leading refrigerant in the cooling industry, offering a carbon footprint 1 774 times lower than conventional alternatives. While its adoption has gained momentum in refrigeration, the HVAC sector has been slower to embrace CO₂-based systems, often favouring refrigerants with higher GWPs. This hesitancy raises important questions— what barriers exist, and how can they be overcome to unlock CO₂’ s full potential in HVAC?

One major hurdle is the difference in operational demands between refrigeration and HVAC systems. Refrigeration typically requires continuous operation, whereas HVAC systems face intermittent loads. Traditional CO₂ systems struggled to efficiently modulate output to match these fluctuating demands. However, recent advancements— such as hightensile pressure components and auxiliary units— now allow CO₂ systems to maintain efficiency even during low-demand periods.

Energy efficiency has also been a concern, as CO₂ based systems historically lagged behind hydrofluorocarbon( HFC) alternatives in performance. But with innovations like advanced power conversion systems and

PHASE OUT PROCESS

Ozone depleting substances Developed countries Developing countries

Halons Phased out end of 1993 Phased out end of 2010 CCl4( Carbon tetrachloride) Phased out end of 1995 Phased out end of 2010 CH3CCl3( Methyl chloroform) Phased out end of 1995 Phased out end of 2015 Hydrochlorofluorocarbons( HCFCs)

parallel compression techniques, modern CO₂ HVAC systems are closing the gap— delivering substantial energy savings while drastically reducing carbon emissions.

DISPELLING MYTHS AND HIGHLIGHTING BENEFITS

Contrary to common misconceptions, welldesigned CO₂ HVAC systems can achieve competitive energy efficiency. Even if they experience minor efficiency losses compared to traditional systems, their near-zero GWP makes them a far more sustainable choice. Given that the built environment contributes at least 40 % of global carbon emissions, transitioning to low-impact refrigerants like CO₂ is no longer optional— it’ s an urgent necessity.

Despite these advantages, conservative mindsets and a lack of familiarity with CO₂ technology remain barriers. HVAC technicians, unlike their refrigeration counterparts, often lack hands-on experience with CO₂ systems. Bridging this skills gap requires comprehensive training programmes and collaboration with engineering partners to ensure proper installation, commissioning, and maintenance.

Additionally, while upfront costs may be higher, the long-term environmental and operational benefits justify the investment. As global demand for air conditioning surges— along with concerns over refrigerant leaks and inefficient systems— the case for CO₂ HVAC grows stronger.

One of the most promising advancements in CO₂ HVAC technology is its ability to provide simultaneous heating and cooling without rigid load balancing. Unlike conventional systems, which require precise load matching, advanced CO₂ setups use intelligent software to dynamically adjust outputs based on real-time demand. This flexibility is particularly valuable in commercial and residential settings where heating and cooling needs fluctuate.

The transition to CO₂ HVAC is not just a technical shift— it’ s a fundamental rethinking of sustainable building climate control. By

Freeze from beginning of 1996 35 % reduction by 2004 75 % reduction by 2010 90 % reduction by 2015 Total phase out by 2020

GWP

The global warming potential( GWP) is a value that indicates the contribution to global warming. The GWP refers to the value of CO2( GWP = 1) as a benchmark. This means that a gas like R404A with its GWP of 3 922 contributes 3 922 times more to global warming than the same amount of CO2. Natural refrigerants have a GWP of 0 to 5.5.

ODP

The concept of the ozone depletion potential( ODP) is used as a measure of the effectiveness of a chemical compound in the degradation to the ozone layer it can cause, relative to the standard compound trichlorofluoromethane( R-11 or CFC- 11) being fixed at an ODP of 1. Natural refrigerants have an ODP of 0.

leveraging proven refrigeration components, high-pressure adaptations, and smart energy management, CO₂ systems are proving they can compete with— and even surpass— traditional HVAC solutions in both performance and sustainability. CLA

Freeze in 2013 at a base level calculated as the average of 2009 and 2010 consumption levels 10 % reduction by 2015 35 % reduction by 2020 67.5 % reduction by 2025 Total phase out by 2030

Hydrobromofluorocarbons( HBFCs) Phased out end of 1995 Phased out end of 1995

Methyl bromide( CH3Br)( horticultural uses)

Freeze in 1995 at 1991 base level 25 % reduction by 1999 50 % reduction by 2001 70 % reduction by 2003 Phased out end of 2005

Freeze in 2002 at average 1995- 1998 base levels 20 % reduction by 2005 Phased out end of 2015

Bromochloromethane( CH2BrCl) Phased out end of 2002 Phased out end of 2002

Hydrofluorocarbons( HFCs) 10 % reduction by 2019 30 % reduction by 2024 70 % reduction by 2029 80 % reduction by 2034 85 % reduction by 2036

FEATURE

Freeze in 2024 10 % reduction by 2029 30 % reduction by 2035 50 % reduction by 2040 80 % reduction by 2045

Grant Laidlaw, owner of Air Conditioning and Refrigeration Academy( ACRA).

Graph by Grant Laidlaw © Cold Link Africa