Hydrofluorocarbons (HFCs)

Hydrofluorocarbons (HFCs) are a group of synthetic gases primarily used for cooling and refrigeration. Many HFCs are very powerful, short-lived climate pollutants with an average atmospheric lifetime of 15 years.

Though HFCs currently represent around 2% of total greenhouse gases, their impact on global warming can be hundreds to thousands of times greater than that of carbon dioxide (CO₂) per unit of mass.

HFC facts

3,790x

The most abundant HFC warms the planet 3,790 times as much as CO₂ over a 20-year period

15 years

HFCs have an average lifespan of 15 years in the atmosphere

Synthetic

All HFCs are human-made for use in refrigeration and cooling equipment

10%

HFC usage is growing at over 10% per year

HFCs were introduced to replace ozone depleting substances and the growing demand for cooling. Their use has grown rapidly over the past several decades. Fortunately, there are many climate-friendly alternatives to HFCs, and emissions can be virtually eliminated by 2050.

The Climate and Clean Air Coalition (CCAC) has campaigned globally since its founding to reduce HFCs. Its partners worked together to get a global agreement to phase down these powerful pollutants through the Kigali Amendment to the Montreal Protocol.

The amendment, which entered into force on 1 January 2019, has been ratified by more than 140 countries. Under the amendment, countries commit to cut the production and consumption of HFCs by more than 80% over the next 30 years to avoid more than 70 billion metric tonnes of CO₂ equivalent emissions by 2050.

Emissions

HFCs are entirely human-made. They are primarily produced for use in refrigeration, air-conditioning, insulating foams and aerosol propellants, with minor uses as solvents and for fire protection.

Most HFCs are contained within equipment, so emissions are the result of wear, faulty maintenance, or leakage at the end of a product’s lifetime.

Even with the full compliance of the Kigali Amendment, the HFCs cooling equipment emits during operation and disposal are untreated in many countries.

HFCs have only been commercialised since the early 1990s, and their abundance in the atmosphere is currently small. They are, however, among the fastest growing greenhouse gases, as demand for refrigeration and air-conditioning increases, particularly in developing countries.

HFCs are accumulating in ‘banks’ of old equipment and will continue to enter the atmosphere through leakage until they are phased out completely. This further necessitates quick action to replace their use in technology to limit the growth of HFC banks.

Global HFC use

Projected trends

Prior to the implementation of the Kigali Amendment, HFC usage was growing at between 10-15% per year. Without action under the Kigali Amendment, emissions of these gases would be on a trajectory to double every five to seven years.

Evidence suggests that the Amendment has contributed to reducing HFC emissions by 20% relative to projections, but more action is needed.

Full implementation of the Kigali Amendment could avoid up to 0.4°C of warming by 2100.

Global HFC emissions (GtCO₂-eq yr^-1)
2022. Velders, Gus J.M. et al.

This graph presents the mean for each scenario.

How the Kigali Amendment reduces climate change

The Kigali Amendment includes practical arrangements for its implementation, including agreements on technologies for the destruction of HFCs and new data reporting requirements and tools.

If fully supported, the Amendment would avoid up to 0.4°C of global warming this century, while continuing to protect the ozone layer. This would substantively contribute to the goals of the Paris Agreement.

HFC impacts

The impacts of HFCs primarily come from their extreme warming effect. Even in relatively small amounts they contribute significantly to near-term warming as greenhouse gases which are hundreds to thousands of times more potent than carbon dioxide (CO2) per unit of mass.

Some highly potent HFCs, such as HFC-23, are still increasing in usage. HFC-23 has a global warming potential (GWP) that is 14,800 times higher than carbon dioxide over 100 years.

Cooling equipment contributes additional climate emissions through its high energy consumption. In 2021, space cooling accounted for nearly 16% of electricity consumption in the buildings sector.

Solutions

HFCs can be most effectively controlled through a phase down of their production and consumption, and replacement with climate-friendly alternatives. All HFCs can be replaced with climate-friendly or natural alternatives.

In addition to the direct climate benefits from HFC mitigation, a global HFC phase down could also provide indirect benefits through improvements in the energy efficiency of the refrigerators, air conditioners, and other products and equipment that use these chemicals. These efficiency gains could also lead to reduced emissions of carbon dioxide and other air pollutants.

Cooling sector solutions