Natural refrigerants: a sustainable cooling solution

(HCFCs)

out by 2020

and 2010 consumption levels 10% reduction by 2015

35% reduction by 2020

67.5% reduction by 2025 Total phase out by 2030

(HBFCs)

end of 2005

by 2005

Phased out end of 2015

reduction by 2036

50% reduction by 2040 80% reduction by 2045

Environmentally friendly refrigerants: cooling the planet without heating it

By Eamonn Ryan

Christopher Visser, CEO of Multilayer Trading, addressed FRIGAIR 2025 on the critical shift towards sustainable refrigerants, emphasising the urgent need for the industry to adopt environmentally friendly options.“Good morning, everyone. It’s great to speak at today’s summit,”

Visser began, setting the stage for a compelling discussion on what he believes is “the single biggest pivot our industry will make in the next decade—choosing refrigerants that cool without heating the planet”.

The urgency of this transition is underscored by exploding cooling demand. Visser cited projections from the International Energy Agency (IEA), stating that “electricity for air-conditioning alone could rise by 500–700 TWh by 2035, almost the output of 150 large power plants.” He warned that continuing to fuel this growth with high- Global Warming Potential (GWP) hydrofluorocarbons (HFCs) would mean “direct emissions wipe out a big chunk of the climate gains we make elsewhere”.

However, Visser offered a positive outlook, asserting, “The good news is: we already have safer, lower-impact options on the shelf. The challenge is matching each one to the right application, safely and economically.” He promised to demystify the complexities of refrigerant choice, providing a clear framework for attendees to implement immediately.

Cooling’s expanding climate footprint

Highlighting the dramatic increase in energy demand, Visser presented IEA data on the ‘Stated Policies scenario’, where “cooling alone adds roughly one terawatt-hour every nine hours worldwide. Annualised, that’s about 1 000TWh—more than three times the growth coming from data centres, and five times that of electric vehicles”.

To put this into perspective, he noted, “If cooling demand were a country, this incremental load would exceed the current electricity use of Brazil. Here in South Africa, Eskom generates about 200TWh a year. The extra global cooling load by 2035 is roughly five Eskom’s worth of new generation.”

Visser attributed these soaring numbers to “rising ambient temperatures and rising living standards, especially in emerging economies”. He stressed the “double climate hit—indirect emissions from electricity plus direct emissions from the refrigerant itself” when high-GWP HFCs are used. “If we’re hunting for the biggest single lever in the power-and-climate equation, cooling comes out on top. That’s why today’s discussion on environmentally friendly refrigerants is so critical.” He emphasised that better refrigerants reduce leakage impact directly and often enable more efficient system architecture.

Policy momentum accelerating the shift

Visser then shifted focus to the regulatory landscape, noting that as of May 2025, 155 out of 198 parties have ratified the Kigali Amendment— that’s about 80% of the world’s GDP under a legally binding HFC phase- down. “Here at home, South Africa ratified in 2022, so we’re aligned with the developing-country Group 1 schedule: a freeze this year, then a 10% cut by 2029, 30% by 2035, and 80% by 2045.”

He warned of potential trade restrictions for non-ratifying countries, particularly concerning “pre-charged equipment”. Visser highlighted stricter regulations in other regions: “Updated European Union regulation bans many over 150-GWP HFCs in new commercial refrigeration from 2025, complete phase-out by 2050. Similarly, in the US, first HFC use- restrictions kick in 1 January 2025; major supermarket systems must move to below or equal to 150GWP by 2027.”

Visser’s message was clear: “The policy train has left the station. If you still specify legacy HFCs like R-404A or R-410A after 2025, you risk supply shocks, price spikes, and stranded assets. “Conversely, he advised, “aligning with under 150GWP options now—CO₂, hydrocarbons,A2L HFO blends—positions you ahead of quotas and taxes”.

Refrigerant families and environmental friendliness

Visser then decoded the complex world of refrigerants, characterising them by safety class (A1,A2L,A3, B2) and GWP. He noted that over 2 000 GWP equals the red zone; rapid phase-down under Kigali; while under 150GWP, the green zone meets 2025 EU and US targets. He singled out R-404A (GWP of approximately 3 900) as being eliminated, and R-32 (GWP of approximately 770) as ‘a bridge option’. For long-term winners, he pointed to R-290 and CO₂ with a GWP of approximately 3 or 1.

He urged technical teams to “steer projects diagonally—from the red A1 zone towards green low-GWP—while ensuring installers are trained for flammability or pressure changes”.

Visser then outlined the five criteria for an environmentally friendly refrigerant:

• GWP-100: “For kilograms CO₂ equivalent per kilogram leaked, Kigali and EU bans target under 150”.
• Whole-life impact –TEWI / LCCP:TEWI or Total Equivalent Warming Impact adds the indirect energy emissions to the direct leaks. In hot climates, electricity often outweighs leakage, so a fluid with slightly higher GWP can still win if it slashes kWh.
• The safety gatekeeper: “ASHRAE classes run A1 non- flammableA2L mildly flammable A3 highly flammable; B2 toxic. Lower GWP usually means either more flammable—propane, HFO blends—or higher pressure, as with CO₂ Training and local codes decide what’s realistic.”
• Economic viability: “Cost per kilogram plus hardware changes— for instance, thicker piping on CO₂. And remember: quotas and carbon taxes will drive legacy HFC prices up sharply after 2025.”

Visser concluded, “A refrigerant is truly ‘environmentally friendly’ only when it clears all four hurdles—climate, energy, safety, and cost—for your specific application.”

The rise of natural refrigerants

Visser provided evidence of natural refrigerants’ widespread adoption, particularly in Europe, where there are “90 700 transcritical CO₂ supermarkets—around one in three stores—and more than 17 million hydrocarbon plug-in cabinets, most running on R-290.” North America and Japan are also seeing significant growth.

Closer to home, Visser shared data from FRIGAIR 2024, revealing “≈ 350 CO₂ transcritical supermarkets up from just 50 five years ago” in South Africa. He added, “Hydrocarbons are spreading even faster: an estimated 51 000 R-290 cabinets… are now in service nationwide. Almost every supermarket is converting freezer and beverage aisles to R-290 plug-ins during every major remodel.” He also noted the emergence of low-charge NH₃/CO₂ distribution hubs commissioned in 2023–24 for industrial users.

Visser presented a case study of a 2 500m² supermarket, demonstrating that a legacy R-404A system “drew 33% more than a modern transcritical CO₂ rack.” He highlighted CO₂’s GWP of 1, making leaks “virtually climate-neutral and Kigali-compliant today”.

For propane (R-290) plug-in retail cabinets, Visser celebrated the 2022 update to IEC 60335-2-89, which lifted the hydrocarbon charge limit to 500g per sealed circuit, making almost all cabinet formats R-290-compatible. He stated that field trials show 30–50 % lower kWh than identical HFC units with R-290, leading to a TEWI shrinks by ~70 % versus legacy HFC cabinets. Visser noted, “Propane is no longer only a solution for small beverage coolers and freezers, it can be used as a solution for the entire store, including cold and freezer rooms.”

The role of low-GWP synthetics: HFOS and blends

Acknowledging that “naturals aren’t always feasible—think split AC units on the 30th floor, “Visser introduced low-GWP hydrofluoroolefins (HFOs) and their blends. He noted that “pure R-1234yf clocks a GWP of 4—a 99 % cut from R-134a.” Blends like R-454C (GWP 148) or R-452B (GWP 676) offer significant GWP reductions without major hardware changes. While these are A2L (mildly flammable),Visser assured that “technician upskilling is the gating item, not the compressor design”.

He described HFOs and blends, as: “The pragmatic bridge with big GWP cuts now, manageable safety tweaks—buying time until naturals or solid-state cooling cover every application.”

Emerging concern: TFA & pfas debate

Visser addressed a growing concern with HFOs: their breakdown into trifluoroacetic acid (TFA). He explained, “Atmospheric oxidation of HFO-1234yf yields TFA with ~100% molar efficiency. The acid is highly persistent and water-soluble. While the UNEP Environmental Effects Panel 2024 calls current human-health risk low, the EU Chemicals Agency’s draft PFAS restriction could capture all fluorinated refrigerants that create persistent degradation products—including TFA.”

His advice to companies was to “diversify portfolios—keep natural refrigerant options ready—and stay engaged in standards work shaping allowable emissions”. He added: “Low-GWP synthetics solve today’s carbon problem, but TFA reminds us that no refrigerant is impact-free— continuous vigilance is part of responsible engineering.”

Selecting the right refrigerant: practical decision rules

Visser presented a decision framework based on “four gates: capacity, policy, safety, economics.”

• Capacity: “Plug-in units hydrocarbons or HFO-1234yf work well. Medium supermarket remote racks CO₂ or low-GWP A2L blends.
• Large industrial loads low-charge ammonia or CO₂ cascade.”
• Policy compliance: “EU and US bans push new commercial systems to under 150 GWP from 2025. Anything above that is short-lived.”
• Safety class: From A1 (non-flammable) to B2 (toxic), he stressed that “A3 = high flammability—great for sealed plug-in cabinets, and with regulation updates, applicable to full store supermarkets.”
• Cost and skills: “While CO₂ racks cost approximately 10% more up front; propane cabinets do not. What refrigerant is best for my climate, and what technicians do I have available to service the refrigerant I select, are considerations.”

Visser urged, “Always aim for the greenest fluid that your safety codes, skill set and budget can handle—that simple hierarchy locks in climate gains without compromising operations.”

Looking to the future,Visser explored technologies aiming to eliminate refrigerants and compressors entirely. He highlighted, “Thermoelectrics, currently a niche but showing promise, with a 2024 field trial cooling a server pod with no moving parts, hitting COP of approximately 2 at 30°C ambient.”

He also discussed ‘Radiative and other passive systems’, such as “spectrally selective films emit heat to outer space even under sunlight, with test roofs showing 4–6°C below ambient”. Another exciting area is solid-state caloric cooling, where materials shift temperature when a field or stress is applied, with a 2023 EU demo producing 1.8 kW at COP of approximately 3.2 using aluminum gallium alloy and no refrigerant.

Visser projected that “solid-state modules would enter mini-fridges and telecom enclosures by 2030; light-commercial splits by mid-2030s, with combined passive and caloric share potentially topping 10% of global cooling capacity by 2045”. He pointed out South Africa’s suitability for radiative panels due to its “high-solar, low-humidity regions”. His final thought on this topic was: “Keep an eye on solid-state and passive hybrids—they could bypass refrigerant debates entirely and reshape cooling within two decades.”

Key take-aways

Visser concluded his presentation with a summary of key takeaways:

• “Rising cooling demand of 1 000TWh extra by 2035—makes refrigerant decisions a frontline climate lever.” “Kigali cuts HFC production 85 % by 2047.”
• “EU F-gas and US AIM Act ban over 150-GWP refrigerants in new commercial systems from 2025–27; South Africa’s phase-down mirrors that timeline.”
• “Naturals already dominate EU supermarkets: 90 700 CO₂ stores, 17 million R-290 cabinets.”
• “SA retail now runs approximately 350 CO₂ supermarkets and 51000 propane plug-ins—technology and skills exist locally.”
• “A2L HFO blends slash GWP 65–99 % and fit existing hardware but produceTFA; regulators are watching PFAS impact, so we need to keep our options open.”
• “A fluid is ‘green’ only if your technicians can handle its pressure or flammability safely. Up-skilling and leak-detection upgrades will make a lasting impact in our market.”
• “Choose the lowest-GWP refrigerant that clears policy, safety and economic gates for your application. Do it now—retrofits later cost more.”