Ultra-potent greenhouse gases still ‘major problem’ – despite global agreement to phase out

EMISSIONS of ultra-potent greenhouse gases are much higher than official reported figures suggest, according to a recent study.

Researchers at the University of Bristol, UK, have found that global emissions of the greenhouse gas HFC-23 are five times greater than official figures reported by governments. One expert described unreported emissions of the gas as a “major problem” in the fight against global warming.

HFC-23 is a greenhouse gas 14,700 times more potent than CO2. Most emissions of the gas are thought to be as a byproduct in the production of another substance, HCFC-22, a feedstock used to make refrigerants, fire protection, and PTFE products such as Teflon.

The latest analysis, published last month in Communications Earth & Environment and based on the most recently available atmospheric readings from monitoring stations around the world, showed HFC-23 emissions measured 14,100 t in 2023. While this is a reduction from 17,300 t in 2019, the figure is five times the target level agreed by more than 160 countries in 2016.

A report last October by the Environmental Investigation Agency (EIA) estimated that 1.56 billion tCO2e of HFC-23 has been released globally since 2016.  

Fionnuala Walravens, a senior climate campaigner at EIA, told TCE: “The issue of unreported and huge HFC-23 emissions is a major problem.” She added that, while most countries have committed to phasing out the gas, “atmospheric data shows that in reality, it’s not happening effectively.

“To address this, we need a range of measures including better transparency and reporting from the production facilities, more use of alternatives to HCFC-22 and bans on use of HFC-23 as a refrigerant and in fire protection.”

She added: “What makes this even more frustrating is how cheap and easy it is to abate this gas.” Walravens estimates that HFC-23 can be abated for “well below” US$1 per tCO2e.

The latest research found that significant emissions originated in eastern China, the world’s largest producer of HCFC-22, despite its 2018 claim to have almost entirely abated HFC-23 from its production of the feedstock. The researchers calculate that China accounts for a third of the global discrepancy between reported and measured HFC-23 emissions.

The researchers also predict significant emissions from other major HCFC-22-producing countries, including India and Russia, but atmospheric data were not available in these locations.

Global agreements

China, India, and Russia are among the 160 parties to both the 1987 Montreal Agreement to phase out ozone-depleting gases, and the 2016 Kigali Amendment which set targets to phase out ultra-potent greenhouse gases including HFC-23. Under the Kigali Amendment, governments are required to report their HFC-23 emissions every year.

HCFC-22 is controlled by the Montreal Agreement, which was signed when ozone-depleting substances gained widespread notoriety for their use as refrigerants. As such, developed countries agreed to completely phase out HCFC-22 by 2020, and developing countries, including India and China, by 2030. HCFC-22 is no longer used directly in cooling technology, but it continues to be used as feedstock for other types of refrigerant gases.

Walravens said: “The main issue is the need to cut production of HCFC-22 and ensure that any remaining production is carried out in facilities which capture the HFC-23 byproduct.”