Global emissions from split air-conditioning systems could decrease 25% by 2050 if propane (R290) units take and maintain a 50% market share, according to a recently published guide to R290 split air conditioners written by the GIZ (the German Society for International Cooperation).
In a business-as-usual (BAU) scenario, the GIZ forecasts that global AC energy demand will more than triple by 2050, with the number of units on the market going from just under 850 million to over 3.7 billion. The growth of the market will lead to a growth in emissions, both in terms of energy consumption and refrigerant leaks.
By 2050, the GIZ projects that split ACs, under a BAU scenario, could emit about 2,750 metric tons of CO2e annually, with around 600 metric tons resulting directly from refrigerant leakage.
“Leapfrogging to high-efficiency appliances using R290 reduces the energy consumption and GHG emissions and thus provides a significant opportunity to contribute to national climate action plans,” the GIZ said.
“Leapfrogging to high-efficiency appliances using R290 reduces the energy consumption and GHG emissions.”
GIZ
Production/leak emissions: The GIZ assessed the production and in-use lifetime leak emissions of a 5kW (1.4TR) split AC unit using HFCs, HFOs and the hydrocarbons propane and propylene (R1270). The estimate assumed an equal energy consumption across all refrigerants to meet energy efficiency label requirements.
- Using a 20-year GWP metric, R410A and R32 produced up to 42 times more CO2e than hydrocarbon refrigerants. R152a and R1234yf emitted up to three times as much.
- Using a 100-year GWP, R410A and R32 produced up to 87 times more CO2e than R290 and R1270. R152a and R1234yf emitted up to 11 times as much.
Economic costs: The GIZ estimated the material cost to construct split AC units for various refrigerants based on producing an equal seasonal efficiency rating and necessary safety measures. The GIZ compared the incremental costs of the units using R410A as the base.
- While the HFC/HFO units are 15 to 120% more expensive than an R410A unit, the hydrocarbon units cost about 20% less.
Evolving standards: The current edition of the International Electrotechnical Commission’s IEC 60335-2-40:2022 standard permits larger charges of A3 refrigerants with mitigation measures, including improved system tightness, airflow provisions and valving that limits leakage.
- According to the GIZ, the new standard “arbitrarily” caps the R290 maximum charge limit at roughly 1kg for indoor installations and 5kg for outdoor installations or within a special ventilated enclosure.
- “[We want] subsequent versions of the standard to suitably reflect the needs of equipment producers, end users and national climate policies,” the group said, encouraging stakeholders to engage in the process. “The standards need to be written in a way that ensures safety, but does not obstruct technology or impose unnecessary or costly requirements.”
Success story: The GIZ highlighted the story of an unnamed Indian manufacturer of R290 single-split ACs, which Bettina Rechenberg, the German Environmental Agency’s Director General of Sustainable Production and Products of Waste Management, called the “most energy-efficient” product on the local market.
- “More than 600,000 units have been sold to end users so far without reported incidents because they were installed by certified personnel,” Rechenberg said. “This example should encourage other governments and manufacturers to introduce R290 solutions to the domestic and worldwide market.”
